.300 Winchester Magnum

History

 
In 1958 Winchester released the .338 Winchester Magnum, a potent, well balanced medium bore cartridge. While a .30 caliber version was highly anticipated - it never came. Wildcatters soon necked the .338 down to .30 caliber which became very popular and was eventually adopted by Norma as the .308 Norma Magnum in 1959.
 
Winchester finally introduced the .300 Winchester Magnum in 1963. Quite unexpectedly the new cartridge featured a much longer case than the .338, as long as could be housed in a Winchester long action, in order to achieve optimum velocities. The shoulder was moved as far forwards as possible to maximize powder capacity, creating a rather short neck, something that had not been attempted before. 
 
Factory ammunition for the .300 Winchester was (and still is) loaded to a very short over all length, allowing the cartridge to be utilized in various brands of rifles with less than optimal length magazines. In this form, the cartridge design was often viewed as a disappointment, suffering such issues as powder cramping and an undesirably long bullet jump / free bore. But with hand loaded ammunition in long magazine rifles such as the Winchester M70 and Remington M700, the .300 Winchester Magnum showed great strengths.
 
Loved or hated, the .300 Winchester Magnum was guaranteed success due simply to the market demand for a readily available .300 magnum cartridge from a major US manufacturer. With factory ammunition offered in a variety of bullet weights, the increasing popularity of the .300 Winchester Magnum resulted in the eventual decline of the .308 Norma while also cutting into a small share of the Weatherby market.
 
The .300 Winchester Magnum gained popularity with 1000 yard competitive shooters for a relatively long period of time, favored for decreased wind drift in comparison to traditional cartridges. The .300 is currently employed by various NATO allies as a sniper rifle cartridge and is also utilized by law enforcement agencies.
 
As a hunting cartridge the .300 Winchester Magnum remains immensely popular worldwide, regardless of new .30 caliber magnum cartridge designs. The .300 Winchester Magnum is both a functional cartridge as well as now being a classic cartridge with a rich history.
 

Performance

The .300 Winchester Magnum is a potent, emphatic killer of light through to large medium game. As with all of the .30 caliber magnums, the key to outstanding success is matching bullet weights and construction appropriately to the job at hand, combined with optimum accuracy.
 
There is an old and long standing argument, which is better, the 7mm Remington Magnum or the .300 Winchester Magnum? This argument pits the two most common factory magnums head to head. In truth, each has its unique strengths. The strengths of the .300 are in its ability to produce fast killing on body weights greater than 90kg. To this end, the rule of this author states, where 90% of the hunters game weights are less than 90kg (200lb), the 7mm magnums show great strengths. If 90% of the hunters game weigh above 90kg, the .300 magnums produce excellent performance. More specifically, on tough game species weighing around 150-200kg (330-440lb), speed of killing can be reduced from 45 seconds (7mm Magnum with conventional bullets) to either instant collapse or a few second delay - at all ranges. Once this is seen in the field and fully understood, arguments about trajectories and wind drift quickly fall by the wayside.
 
Loaded with 150 grain bullets, the .300 Winchester Magnum can be utilized as an emphatic and spectacular killer of light framed game out to considerable ranges. With factory ammunition the .300 Winchester Magnum often does some of its best work with 150 grain offerings, regardless of the lower than optimal BC’s. For light framed deer, which covers many of the world’s deer species and also antelope species, many 150 grain factory loads produce spectacular killing.
 
Loaded with 165-168 grain bullets, the .300 Winchester Magnum produces emphatic killing on medium to larger bodied deer species. Most projectiles of this weight tend to work best on body weights of between 90 and 150kg (200-330lb), however, specific styles of bullet can be employed to increase versatility where lighter game may be encountered or at the other extreme, where heavier, very tough game may be encountered.
 
Loaded with 180 grain bullets, the .300 Winchester magnum excels on large body weights, specifically on game weighing between 90 and 320kg (200-700lb). Again, the choice of bullet construction enables increased versatility.
 
Loaded with 200 to 220 grain bullets, the .300 Winchester magnum can be put to use on large, heavy bodied game. Exceptionally deep penetration can be achieved with select bullet designs however wound channels through heavy animals are not as wide or as fast bleeding as can be achieved with a wider bore. When using the .300 on large game, shot placement is the key. On bovines, head or neck shots ensure the fastest possible kills. However, such shots should only be taken with a rifle of proven accuracy at close to moderate (depending on the skill of the shooter) ranges.
 
Loaded with frangible long range bullets, the .300 Winchester Magnum is truly outstanding. The trajectories of this cartridge should never be compared with the 7mm’s, focusing instead on the strengths of heavy 178-208 grain projectiles, capable of rendering deep, immensely broad wounding on larger bodied deer species (as well as light framed game), both at close ranges, all the way out to and beyond 1200 yards.
 
The .300 Winchester Magnum produces significant and very sharp recoil in unbraked light to medium weight sporting rifles. Short eye relief scopes further accentuate felt recoil and brands such as Swarovski and Zeiss should be avoided on medium weight unbraked rifles, unless shooters are determined to pay several thousand dollars for a punch in the eye. Unbraked, the most comfortable (mild recoiling) factory hunting rifle is without a doubt the Remington M700 Sendero.

   

Factory Ammunition.

 
Winchester’s initial factory loads for the .300 featured a 150 grain bullet at 3400fps and a 180 grain bullet at 3070fps, both loads have since been reduced. Most manufacturers presently advertise velocities of around 3290fps with 150 grain bullets and 2960fps with 180 grain bullets. In sporting rifles with 24-26” barrels most 150 grain loadings achieve realistic velocities of around 3250fps while 180 grain loads achieve around 2880fps.  
 
Present 150 grain loads from Winchester Olin include the 150 grain PowerPoint at an advertised 3290fps, the 150 grain XP3 (replacing the Failsafe) at 3260fps and the 150 grain Nosler E-Tip, also at 3260fps. The 150 grain PowerPoint is a highly explosive projectile, producing spectacular performance on light framed game out to ranges of around 300 yards, limited by BC. The 150 grain Failsafe was much too stout, delivering very narrow wounds, especially at extended ranges. Olin’s newest bullet, the 150 grain Elite XP3 attempts to overcome these problems. Designed in a similar fashion to the Failsafe, the Elite does away with the steel heel of the Failsafe and instead has a bonded rear core to prevent jacket core separation. The front section still consists of solid copper but with the addition of a polymer tip as well as a boattail to reduce drag in flight. At close ranges, where impact velocities are high, the bonded shank expands into a bulb, similar to Swift’s A-Frame, the change in form enabling vivid energy transfer. Essentially the Elite is a reverse design of the Trophy bonded Bear Claw which has a solid copper shank and bonded lead front. The 150gr Elite is advertised as being ideally suited to both light and heavy, soft skinned game. However, beyond 150 yards, as velocity falls below 2900fps and especially at the velocity parameter of 2600fps, the 150gr XP3 is somewhat better suited to game weighing between 90 and 150kg (200-330lb). The inclusion of the 150 grain E-Tip load is due to certain state laws within the U.S, banning the use of lead cored projectiles in order to save the environment from humanity. This is a tough projectile, again, producing best performance on game weighing between 90 and 150kg, working well on light framed game at close ranges, producing delayed killing as velocity is shed. 
 
Heavy loads from Olin include the 180gr PowerPoint at an advertised 2960fps, the 180 grain Ballistic Silver Tip at 2950fps, the 180 grain Accubond at 2950fps, the 180 grain XP3 at 3000fps and the 180 grain Nosler E-Tip at 2950fps. Individual rifles do sometimes achieve Olin’s stated velocities, especially Lubalox coated loads which have been designed to help sporting rifles achieve maximum velocities, however, it is also not uncommon for loads to average the fore mentioned average of 2880fps with this bullet weight.
 
The 180 grain PowerPoint is an explosive bullet and is one of the few 180 grain projectiles capable of producing truly fast killing on light framed animals. Due to the explosive nature of this projectile, the PP is not well suited to heavy bodied game at close ranges, but instead produces admiral performance on all game up to weight of around 150kg. 
 
The 180gr Ballistic Silver Tip is far stouter than the PP, a slow killer on light animals but an extremely good performer at long ranges on body weights between 90 and 150kg (200-330lb), tackling larger body weights of up to 320kg (700lb) as velocity falls below 2200fps. The companion to this projectile, the 180 grain Accubond features the same form as the BST and used in conjunction with the BST as a dual load, is capable of tackling large bodied deer at close ranges, producing fast killing at impact velocities of 2600fps and above (inside 200 yards), clean but slightly delayed killing down to 2400fps (300 yards) and clean but further delayed killing as velocities fall to 2200fps (inside 430 yards). The Accubond is capable of producing good, but not outstanding penetration on large bodied deer, its design wrestling with the balance of optimum energy transfer versus sufficient penetration.
 
Olin’s two stout bullet designs, the XP3 and E-Tip are both best suited to game weighing above 90kg, being well suited to game weighing right around the 320kg (700lb) mark. Both projectiles can be put to use on larger game however, wound channels are not nearly as broad as can be produced with a wider bore, necessitating selective shot placement. Field experience, autopsies and record keeping are key factors when exploring any of the .300 magnums for use on large bodied game.
 
Current light weight offerings from Remington include the 150gr Core-Lokt and the bonded Core-Lokt Ultra at 3290fps. The Core-Lokt is also offered as a managed recoil load at a very nice 2650fps. Both the 150 grain Core-Lokt and the Ultra core bonded bullets are excellent light game performers, the traditional Core-Lokt is so much so, that it is immensely frustrating that it has such a low BC, suffering excessive wind drift and loss of velocity, duplicating the muzzle velocity of the .30-30 at just 270 yards. Both projectiles have a tendency to expand to very wide diameters at close ranges, inhibiting penetration when used on larger body weights with raking shots. The traditional Core-Lokt is quite simply a spectacular killer on game weighing up to 80kg out to moderate ranges, the Ultra does its best work at impact velocities of above 2600fps if used on light framed game, working well on larger body weights of up to 150kg, producing delayed killing at impact velocities of 2400fps, producing slower killing again at 2200fps (340 yards).
 
Heavy weights from Remington include the 180gr Core-Lokt, the 180 grain Accutip, the 180 grain Ultra and the 180 grain Scirocco, all at an advertised 2960fps for true velocities of around 2880fps. The heaviest load, features the outstanding 200 grain A-Frame at 2825fps for a realistic 2750fps.
 
Remington’s traditional 180 grain Core-Lokt is an excellent bullet for use on large bodied deer out to moderate ranges. The reliable Core-Lokt is able to penetrate vitals from most angles with little risk of bullet blow up. The 180 grain Ultra retains a lot more weight than the traditional Core-Lokt after impact, producing very good but not substantially deeper penetration than the former design. The Ultra finds its strengths at close ranges on large bodied game weighing up to and around 320kg.
 
Remington’s 180gr Accutip (Hornady SST) is an excellent general purpose load. It should not be used with heavily angling shots on large bodied deer at close ranges due to a high risk of bullet blow up but is a fast killer when used on light game at close ranges and on game weighing between 90 and 200kg from point blank, out to ranges of around 770 yards, quite an outstanding load.
 
The 180gr Swift Scirocco is vastly better than the Ultra and in this regard, it is odd that Remington promote both loads. The 180 grain Scirocco is incredibly fast expanding when used at close ranges on light through to large bodied deer, often producing spectacular kills. When used on lighter animals beyond 100 yards, this bullet will sometimes give a spectacular poleaxing effect due to spinal shock, followed by a quick recovery and escape. Death from blood loss occurs a little while after. At extended ranges of around 300 yards, lung wounds on light framed game can be less than an inch in diameter. The 180 grain Scirocco is far more suited to game weighing between 90 and 320kg (200-700lb) where it meets enough resistance to initiate widest possible wounding for fast, emphatic killing. The Scirocco does have a tendency to over expand at closer ranges when used on tough game due to the vast amounts of energy transferred upon impact and cannot be expected to penetrate vitals on game the size of elk with raking shots. Nevertheless, this should not be seen as a detractor in comparison to its great strengths. As with most core bonded designs, performance tends to wane at 2400fps, with wounds becoming much narrower at 2200fps and below.
 
The 200 grain A-frame is a hard hitting, highly traumatic, deep penetrating bullet. Ideal for large, tough, hardy game out to moderate ranges of around 200 yards, the 200 grain A-Frame is a reliable performer. On Bovine sized animals, as is continually reiterated, neck or head shots produce best results.
 
Federal’s current light weight loads include the 130 grain Barnes TSX at a sizzling 3500fps and the 150gr Speer Hotcor at 3280fps. The entry level Hotcor is a fast killer on light game although at ranges under 100 yards, like most 150gr .30 calibre magnum bullets, it struggles with raking shots and can be pushed to the point of failure. Nevertheless, with ordinary cross body shots, the Hotcor is quite tough, producing an excellent combination of good penetration versus exceptionally wide wounding, rendering exit wounds of up to 3” in diameter when used out to moderate ranges. This really is a good load for general work on light framed game out to ranges of around 300 yards. The 130 grain TSX is a very recent offering from Federal. This load is flat shooting, hard hitting out to ranges of around 400 yards, wide wounding, yet with minimal meat damage at moderate to extended ranges. The 130 grain TSX is a very versatile bullet, capable of handling a wide range of game species up to 150kg (330lb) along with heavier body weights in a pinch.
 
Medium weights from federal include the 165 grain Nosler Partition, the 165 grain TSX and 165 grain Tipped TBBC, all at 3050fps, giving around 2970fps or faster in sporting rifles. The Partition is a fast expanding bullet design and although it is best suited to game weighing between 90 and 180kg (200-400lb), this bullet produces wide wounding on light framed game as well as versatility on larger body weights, an excellent performer down to velocities of around 1800fps. The tougher TTBBC and TSX are much better put to specialized, game specific tasks, useful on game weights above 90kg, emphatic on game weighing around 200kg (440lb), out to ranges of around 300 yards.
 
Federal’s heavyweights include the economical 180gr Hotcor, the 180 grain Partition, the 180 grain Accubond, the 180 grain TSX and the 180 grain TTBBC at an advertised 2960fps. The toughest load from Federal, features the 200 grain TBBC at 2700fps.
 
The 180 grain Hotcor is a good performer, never really prone to bullet blow up, producing wide wounds and acceptable penetration on large bodied deer. On light framed game, killing can be quite delayed, requiring the often quoted 90kg resistance, also producing adequate results on game up to 320kg when used as a cross valley (300 yard) type load. The Nosler Partition has a very soft front core, producing fast expansion, yet, is still better suited to larger body weights as opposed to a general purpose load. A violent performer, the 180 grain Partition gives spectacular kills when matched to appropriate body weights.
 
Federal’s 180 grain Accubond load duplicates the Olin loading, a fast killing bullet ideal for large bodied deer out to moderate ranges. As can be expected, the tougher TTBBC and TSX do their best work on large, very tough animals at impact velocities above 2400fps (240 yards). The two are not however completely the same, the TTBBC having a greater tendency to induce trauma, causing coma very quickly, minimizing pain. The 200 grain TBBC (non-tipped) is again, a hard hitting, highly traumatic, deep penetrating bullet. Best performance occurs inside 150 yards where velocity remains above 2400fps.
 
Current light weight loads from Hornady include the 150 grain Interlock BTSP and the 150 grain SST at 3275fps. These are good light game loads, producing fast, emphatic killing. Under 150 yards, the Interlock and SST are both prone to suffer complete bullet blow up with raking shots, therefore, for optimum results, these loads are best used on game weighing no more than 80kg (180lb). Of the two loads, the 150 grain SST is a stellar performer, rendering wide wounding down to velocities as low as 1600fps or from a typical muzzle velocity of 3250fps, around 800 yards.
 
Hornady’s medium weights include the 165gr Interlock BTSP and the 165 grain SST at 3100fps. Along with this, two Superformance loads are included, featuring the 165 grain InterBond and 165 grain GMX at 3260fps. 
 
The 165gr Interlock BTSP is a good, basic general purpose deer bullet, producing good results without fuss. In recent years though, the SST has really out shone the BTSP, a very violent bullet. The 165 grain SST is best suited to game weighing between 80 and 150kg while also producing fast killing when used on light framed game out to moderate ranges, continuing to produce clean but slightly delayed killing of light framed game at extended ranges. Unfortunately, the huge amount of energy generated by the .300 Winchester Magnum places the 165 grain BTSP and SST bullets under a great deal of strain when used at woods ranges, neither are capable of reliably withstanding raking shots on larger bodied deer at ranges under 150 yards. For closer range work on medium to larger bodied deer, both the InterBond and recent GMX are deep penetrating projectiles, the InterBond producing very broad, fast bleeding, fast killing wounds.
 
Hornady’s heaviest loads include the 180gr Interlock and the 180 grain SST at 2960fps along with the 180 SST SF and the 180 grain InterBond SF loadings at 3130fps. There was a time when the 180 grain Interlock gave consistently faster kills on lighter framed game at close ranges than most other .30 caliber hunting bullets, a generally good load for all game up to 150 to 180kg (400lb). Now, the SST leaves the Interlock looking a bit lack luster, rendering wide wounds on light bodied game, producing fast killing at impact velocities above 2600fps. In its standard guise, the 180 grain SST produces fast killing on light body weights to a range of 150 yards, in the Superformance loading, this range is extended out to 260 yards. As a large game load, for which it was designed, the 180 grain SST is best suited to body weights of between 80kg and 150kg (180-330lb) while being capable of tackling larger body weights of up to 320kg when used as a dedicated long range load, showing a general increase in penetration below 2600fps while continuing to produce wide wounding down to 1600fps.
 
Hornady’s 180 grain SF InterBond load is hard hitting and violent when used on game weighing between 90 and 320kg. This bullet does its best work at impact velocities of 2600fps and above (inside 250 yards), continuing to produce wide, fast bleeding wounds at 2400fps but with sometimes delayed killing with performance tapering off at 2200fps.
 

Hand Loading

 
Standard twist rate for the .300 Winchester magnum is 1:10, ideal for heavy bullets but often producing acceptable results with 150 grain bullets at mild muzzle velocities of 3250 through to 3320fps as a typical upper limit for accuracy.
 
When hand loading for the .300 Winchester Magnum, rifle magazine length has a great influence on the ease of operations. There are still many manufacturers chambering the .300 Win Mag in rifles that feature short magazines, potentially (but not always), producing less than desirable and sometimes frustrating performance with hand loaded long for caliber projectiles. A minimum internal magazine length of 90mm (3.543”) should be sought for best results. In short magazine rifles, powder charge rate experimentation is a key factor towards developing accurate hand loads.
 
It is difficult to seat 150gr bullets out of the short neck of the .300 Winchester for minimal bullet jump and any cartridge length beyond 86mm (3.386”) can run the risk of accuracy loss through bullet to bore misalignment (lack of concentricity). A long bullet jump with 150 grain bullets is to be expected, requiring attention to both powder charge rate experimentation and optimal seating depths for concentricity.
 
Like all belted magnums, but more especially because of the long jump required when using 150gr bullets, it is important to neck size the .300 Win magnum for optimum concentricity. This head spaces the case at the shoulder and the belt at the same time, rather than the belt, at the rear of the cartridge. If cases are reduced in size too heavily, accuracy can be effected, the cartridge head spacing at the belt first, then the shoulder in a secondary motion.   
 
In minimum dimension chambers, full length sizing may be required in order to avoid difficulty chambering ammunition. In these instances, the chamber is so tight, that head spacing will still occur at both the belt and shoulder, regardless of the full length resizing operations.
 
In the past, target shooters reported good results when using medium/slow burning powders in the 4350 range, obtaining accurate loads with 172 to 190 grain bullets driven at mild velocities. When loading for full power, the most versatile powders in the .300 Winchester Magnum are those in the H4831/ADI2213sc range, though powder compression can occur in short magazine rifles before full pressures are obtained. Slower powders such as H1000/ADI2217 and IMR7828 work well with heavy 200 to 220gr bullets in long magazine rifles. This burn rate can also be used for improving the bulk density of reduced loads, allowing the hand loader to duplicate .308 Winchester velocities.
 
From a 26” barreled rifle with an adequate magazine length, achievable velocities (standard primer) include 3320fps with 150 grain bullets (often losing accuracy thereafter due to twist rates and bullet jump), 3230fps with 165-168 grain bullets, 3125fps with the 175 grain VLD, 3070fps with 178-180 grain bullets, 3020fps with the 185 grain VLD, 2970fps with 190 grain bullets, 2870fps with 200 grain bullets, 2800fps with 208-210 grain bullets and 2700fps with 220 grain bullets. The .300 WM does however have a tendency to display nonlinear results. For example, in many rifles, it is possible to achieve velocities of 2950-3000fps with 200 grain bullets. These discrepancies can become even larger with the soft jacketed, low pressure inducing 208 grain A-Max which can display desirable pressure/accuracy relationships at muzzle velocities of up to 2950fps depending on individual chamber and bore dimensions. In essence, the .300 Winchester Magnum does very well with heavy bullets.
 
As always, when testing full power loads, it is imperative that the shooter has both good technique to tame recoil and that the rifle has a sound bedding platform. Otherwise, loss of accuracy at high muzzle velocities can easily be misread.
 
Hunting projectiles from Sierra include the 150 grain GameKing, 150 grain Prohunter, 165 grain GameKing, the 165 grain GameKing HPBT, the 180 grain GameKing, the 180 grain Prohunter, the 180 grain round nose, the 200 grain GameKing and 220 grain round nose. Sierra match bullets are mostly unsuitable for hunting, however, the 168gr SMK (BC .462) and 175 grain SMK (BC .505) can be used to great effect on wild boar.
 
The 150 grain GameKing is best suited to light bodied game weighing up to 70kg (155lb) as a safe maximum. This bullet is highly frangible in the .300WM, exploding on impact at close ranges, producing devastating results. That said, where a light bullet is to be used as an all-round load where game may be encountered at close ranges, a stout jacketed projectile can produce more emphatic killing. The tougher 150 grain Prohunter gives exceptional performance as an inexpensive, 300 yard light game load in the .300 WM. The GameKing tends to excel at ranges between 150 and 550 yards.
 
Sierra’s 165 grain GameKing SBT and HPBT are stout bullets. One might expect that at .300 WM velocities, these would produce fast killing on light framed game but field results show that velocity is a secondary factor. These projectiles give best performance on game weighing between 80 and 150kg (180-330lb).
 
The 180 grain GameKing produces wide wounding on game weighing between 90 and 180kg (200-400lb) out to ranges of around 500 yards. On larger body weights, the 180 grain GameKing comes into its own at impact velocities of between 2400fps and 2000fps, opening up to produce a huge frontal area, but often without fragmentation. The stout 180 grain Prohunter produces emphatic killing on game weighing between  90 and 180kg (200-400lb), producing good performance on heavy deer species of up to 320kg (700lb) with ordinary cross body shots, producing wide wounding out to 300 yards (2400fps), showing a gradual decline in wounding towards 2200fps (400 yards), producing clean but often delayed killing. 
 
Sierra’s 180 grain round nose is an exceptional woods hunting bullet, producing fast kills on all body weights up to 200kg (440lb), an often spectacular killer at impact velocities of above 2600fps. Likewise, the 220 grain Sierra round nose driven at magnum velocities produces immediate energy transfer on light through to larger bodied deer species weighing up to 320kg, an excellent, inexpensive bullet.
 
Speer hunting bullets include the 150 grain BTSP, the 150 grain Hotcor SP, the 150 grain round nose Hotcor, 150 grain protected point Mag Tip, the 165 grain Hotcor, the 165 grain BTSP, the 180 grain Hotcor, the 180 grain BTSP, 180 grain Mag Tip, the 180 grain round nose Hotcor and the 200 grain Hotcor.  Speer’s latest development is the Deep Curl range of premium core bonded bullets in the weights 150, 165, 180 and 200 grains (untested at this time of writing).
 
The 150 grain Speer BTSP is unfortunately too frangible for all-round light game work where close range shots may be encountered. Optimum results, combining wide wounding with adequate penetration are achieved between the velocity parameters of 2700fps through to 1800fps. The 150 grain Hotcor is a spectacular light game bullet, very much like the Prohunter, a good 300 yard bullet.
 
The 165 grain Speer BTSP is an excellent bullet for the .300WM for use on all game, up to body weights of 150kg (330lb). The BTSP has an exceptional BC of .520, producing wide wounding out to ranges of around 860 yards. In contrast, the 165 grain Hotcor is very stout, producing best performance on game weighing between 90 and 150kg (180-330lb) out to ranges of around 350 yards.. 
 
The 180 grain Speer BTSP is a highly frangible projectile. BC is .545 and this bullet hits hard, all the way out to 800 yards. The 180 grain BTSP is perhaps a little too soft for use on the largest of deer (320kg/700lb) at very close ranges, coming into its own as velocities fall below 2400fps (400 yards), obtaining deep penetration at 2000fps. On mid sized deer and game species weighing between 70 and 180kg (155-400lb), this is a violent, extremely fast killing all range bullet.
 
As can perhaps be expected, the stout 180 grain Hotcor is ideally suited to game weighing between 90kg and 320kg out to ranges of around 400 yards. Performance is near identical to the Sierra Prohunter, regardless of differences in bullet manufacturing techniques. When matched appropriately to game, this very basic projectile hits very hard, resulting in immensely fast kills. The 200 grain Hotcor is an outstanding, emphatic killer, ideal for body weights between 90 and 400kg (200-880lb) and adequate for larger game when utilizing selective shot placement. Best performance is achieved at impact velocities above 2400fps.
 
Hornady 150 grain bullets include the 150 grain flat base soft point Interlock, the 150 grain BTSP Interlock, the 150 grain SST and the 150 grain InterBond.
 
As a light game load, either the 150 grain BTSP or FBSP Interlock driven at a mild 3250fps can be used with great success on game weighing up to 70kg (155lb). Hydrostatic shock tapers off at 2600fps (most conventional bullets/brands the same) or 240 yards while wounding steadily tapers off at 2400fps, though wounds are still adequately wide for very clean killing at 2000fps (500 yards).
 
Hornady’s 150 grain SST is an exceptional projectile. Again, hydrostatic shock tapers off at 2600fps, however wounding remains very broad down to 1600fps. The 150 grain SST works well on game weighing up to 80kg (180lb). The 150 grain InterBond is a versatile bullet where light through to mid weight game (up to 120kg) may be encountered at woods ranges, through to cross valley shots of up to 400 yards. This bullet should not be overlooked as it can be much more effective than a heavy, conventional bullet which may allow lean game to escape (dead run), lost to the hunter, especially in steep woods/bush country.
 
Medium weight bullets from Hornady include the 165 grain BTSP Interlock, the 165 grain flat base soft point Interlock, the 165 grain SST and the 165 grain InterBond, all ideal for game weighing between 80 and 150kg (180-330lb). 
 
The 165 grain Interlock is an easy to work with projectile, inexpensive and clean killing out to ranges of around 600 yards. The more dramatic SST is an excellent bullet. As has been reiterated throughout the .30 caliber texts, while this bullet is ideal for mid weight game, it produces wide wounding on lean, light framed game and although killing may be delayed on lean game, the delay is not nearly slow as is often experienced with other projectile designs. In the .300WM, the 165 grain SST is useful out to 850 yards (1600fps). The 165 grain InterBond is well suited to the .300WM, for use on game weighing between 80kg and 200kg (180-440lb) while also producing acceptable wounding and penetration on heavier deer/antelope species of up to 320kg (700lb). Best performance is achieved inside 400 yards (2400fps) and especially above 2600fps (300 yards).
 
Heavy bullets from Hornady include the 180 grain flat base soft point double cannelure Interlock, the 180 grain BTSP Interlock, the 180 grain round nose Interlock, the 180 grain SST, the 180 grain InterBond, the 190 grain BTSP and the 220 grain round nose Interlock.
 
The 180 grain Hornady Interlock is a soft projectile working well on game weighing up to 150kg (330lb) and up to 180kg as velocities approach 2800fps, tackling larger body weights with further reductions in velocity. The 180 grain SST is spectacular in performance, a very effective hunting bullet. Like the soft point, at close ranges, penetration can be shallow, but adequate for game weighing up to 150kg. As velocity falls away, larger body weights can be tackled and as a long range load driven at 3070fps, the SST produces traumatic wounding on medium game out to 600 yards.
 
The 190 grain BTSP Interlock was designed specifically for the .300WM. This projectile gives best results on game weighing between 90 and 200kg (200-440lb), out to ranges of around 550 yards. Hornady’s heaviest load, the 220 grain round nose is unfortunately a little too soft for use on large bodied game and in the magnum, is best suited to game weighing up to 150kg (330lb) at woods ranges. 
 
Hornady A-Max bullets are made in the weights 155, 168, 178 and 208 grains. The 155 grain A-Max is a little too soft for use in the magnum if closer range shots are to be encountered. For small or lighter framed game, the 168 grain A-Max is as light as one needs go. Even the 208 grain A-Max produces fast killing on game as light as 15kg (33lb) at 1400fps. The 168 grain A-Max is best utilized on game weighing less than 80kg (180lb), out to ranges of around 1050 yards.
 
The 178 grain A-Max is a good long range bullet, ideal for light framed game, adequate for use on game weighing up to 150kg if shots have to be taken at close ranges, excelling at longer ranges, again, out to 1050 yards (1400fps), breaking the sound barrier at 1360 yards. Nevertheless, where possible, the 208 grain A-Max deserves full experimentation. This last projectile is a true powerhouse, whether loaded at 2800fps or in rifles that allow muzzle velocities of up to 2950fps. At 2800fps, this projectile renders wide wounding out to 1190 yards, becoming subsonic at 1600 yards, handling a huge range of game species up to 320kg (700lb).
 
Nosler produce Ballistic Tip bullets in the weights, 150, 165, 168 (Combined Technologies) and 180 grains. The explosive 150 grain BT is very similar to Sierra’s 150 grain GameKing, performing best at long but not true long ranges, a traditional open country bullet for light framed game. The 165 and 168 grain BT bullets are like so many designs, best suited to game weighing between 80 and 150kg (180-330lb). The 180 grain BT is best suited to deer species weighing above 90kg (200lb). As velocity falls away, the more these projectiles are able to produce deep penetration on large bodied deer.   

Nosler Partition bullets are available in the weights 150, 165, 180, 200 and  220 grains. The 150 grain Partition is very well suited to the .300WM, maximizing speed of killing on light bodied game without risk of shallow penetration. Ideal for game weighing up to 100kg, but capable of tackling game weighing as heavy as 150kg (330lb), this projectile produces wide wounding out to 650-700 yards, though performance is limited by wind drift.

The 165 Partition driven at 3230fps produces violent performance on game weighing between 80 and 180kg (180-400lb) out to 680 yards, also giving excellent penetration where raking shots are to be encountered. The 180 grain Partition goes further, giving fast kills on game weighing up to 320kg (700lb) out to 700 yards (1800fps).
 
Nosler’s 200 grain Partition is an exceptional bullet for use on game weighing between 200-450kg 440-1000lb). The slight reduction in muzzle velocity in comparison to the 180 grain Partition ensures somewhat deeper penetration on all game when used at woods ranges. The same applies to the 220 grain Partition, an immensely hard hitting big game/ moderate range hunting bullet. On game heavier than 450kg, the .30 calibers are not nearly as effective as the wider bores and although the heavy Partitions perform admirably, neck and head shots produce best results.

Nosler Accubond bullets are available in the weights 150, 165, 180 and 200 grains. The 150 grain Accubond is a good light game bullet like the InterBond, Scirocco and Partition. Of the premium designs, this projectile tends to shed more weight than is competitors but when matched appropriately to game weights, works very well.  

The 165 grain Accubond produces excellent wounding and penetration on game weighing between 90 and 150kg (200-330lb). The 180 grain Accubond gives best results on game weighing between 90 and 180kg at close ranges, giving deeper penetration as velocities fall below 2900fps where it becomes more effective on game weighing up to 320kg (700lb) out to (500 yards).   
 
Swift bullets include the 150, 165 and 180 grain Scirocco projectiles along with the 165, 180 and 200 grain A-Frame bullets. The 150 grain Scirocco is yet another good, light to medium weight deer bullet. This projectile has a long bearing surface with the potential to produce desirable accuracy from 1:10 twist barrels. The 165 grain Scirocco is, like the InterBond and Accubond, best suited to game weighing between 90kg and 150kg (200-400lb). The 180 grain Scirocco gives best results on game weighing between 90 and 320kg (200-700lb) out to a maximum range of around 500 yards. Annealing vastly improves the ability of the Scirocco to penetrate vitals from most angles (but not tail on shots) when used at woods ranges on large, tough animals (the forte of the A-Frame). The Scirocco really dumps vast amounts of energy on impact, a projectile that is immensely effective when matched to game.
 
The 180 and 200 grain A-Frame bullets are simply brilliant moderate range large game bullets. As suggested in the .30-06 text, these projectiles, particularly the 200 grain A-Frame when used at .300WM velocities, maximize stopping power on tough animals, particularly bear. Unrecoverable trauma and deep penetration are key performance factors. Maximum range for fast killing is where velocity reaches 2350fps.
 
Barnes bullets include the 130, 150, 165, 168, 180 and 200 grain TSX bullets along with the 150, 165 and 180 grain MRX bullets (MRX untested).
 
The Barnes 130 grain TSX is a good all-round bullet for game weighing up to 150kg. A great projectile that produces fast kills with no fuss, as suggested in the Federal factory ammunition section.
 
The 150 grain TSX bullet is not unlike most conventional 165-180 grain .30 caliber bullets, best suited to game weighing between 90 and 150kg (200-330lb), but capable of handling much heavier game out to ordinary hunting ranges. The 165 and 168 grain TSX bullets require a good deal of resistance, not to promote wounding as the Barnes TSX always produces good vital wounding, but to promote fast anchoring of game. The 165 to 180 grain TSX bullets all require body weights of above 90kg (200lb) and up to 320kg (700lb) to really shine. As for penetration, the 180 grain TSX, even at point blank ranges where the projectile should be placed under excessive strain, will exit the offside shoulder of a 700kg (1540lb) bovine. Its only weakness, is the .30 caliber bore diameter, limiting width of wounding through the largest of game.
 
For those who intend to hunt large bodied game, a packet of Woodleigh projectiles tucked away is a great thing. Woodleigh bullets are designed in such a way that the hunter can choose from a variety of bullet tolerances, fast, versus delayed expansion and so forth. These projectiles really come into their own on heavily muscled animals. The 180 grain Protected Point (PP) Magnum is a good general purpose bullet for use on large bodied deer, specifically designed to work well at magnum velocities. Likewise, the 200 grain PP Magnum is ideal for use on tough game up to 450kg (1000lb). The 220 grain round nose produces a combination of fast expansion on large but lean game as well as optimum penetration on heavy game. The 240 grain PP is a straight out hard hitting, deep penetrating bullet when used at close to moderate ranges.
 
Berger VLD long range hunting bullets are produced in the weights 155, 168, 175, 185, 190 and 210 grains. Being slightly stouter than the A-Max bullets, these can be very useful on larger body weights.  The 175 and 185 grain VLD bullets are well suited to game weighing between 80 and 150kg, producing violent performance out to ranges exceeding 1200 yards. It must however be reiterated, if the VLD does not meet enough resistance, the cut off point for broad wounding is around 1600fps, higher if the bullet weight is grossly mismatched to game weights. The 190 and 210 grain VLD bullets are best suited to very large bodied deer, the 210 grain excelling in this role.
 
A last, stand-alone bullet design that we don’t really see anymore is the 180 grain Norma Vulcan. This is an outstanding bush/woods hunting projectile suitable for all game up to weights of around 150kg where spectacular performance is concerned. The flat tipped Vulcan has a terrible BC, but its killing performance cannot be overlooked, anchoring game from every angle, anchoring game where snap shots have resulted in shot placement error, a hammer of Thor. In Europe, the 180 grain Vulcan has in the past been used as a Moose bullet, but its greatest strengths really are with those difficult woods hunting snap shots on light through to medium weight game.
 

Closing Comments

 
A hunter carrying a .300 Winchester Magnum in the field has a flat shooting, potent cartridge, ideal for both bush work and long range hunting of light through to large medium game. That said, bullet weights must be matched to game weights and bullet construction matched to hunting environment in order to achieve optimum results. Along with this, the hunter must be able to shoot MOA or less in order to utilize this cartridge’s potential, whether the .300 is to be used at 250 yards or 1250 yards. The .300 Winchester Magnum demands honesty and attention to detail and for those who are willing, offers exceptional performance in return.
 
 
 

Suggested loads: .300 Winchester Magnum					Barrel length: 26”
No	ID		Sectional Density	Ballistic Coefficient	Observed  MV Fps	ME Ft-lb’s
1	FL	Hornady 150gr SST	.226	.415	3250	3517
2	FL	Hornady 180gr SST SF	.271	.480	3130	3915
3	FL	Federal 180gr Partition	.271	.474	2880	3315
4	FL	Federal 200gr TBBC	.301	.392	2700	3237
5	HL	150gr Accubond/ BT 150gr Scirocco	.226	.435	3320	3671
6	HL	165gr SST	.248	.447	3230	3822
7	HL	178gr A-Max	.268	.495	3070	3725
8	HL	180gr Scirocco	.271	.520	3070	3766
9	HL	200gr Woodleigh PP 200gr A-frame	.301	.450	2870	3657
10	HL	208gr A-Max	.313	.648	2800	3620

 

Suggested sight settings and bullet paths
1	Yards	100	175	300	341	375	400	425	450
	Bt. path	+3	+4	0	-3	-6.3	-9.1	-12.3	-15.9
2	Yards	100	175	290	331	350	375	400	425
	Bt. path	+3	+3.8	0	-3	-4.7	-7.2	-10.2	-13.5
3	Yards	100	150	260	300	325	350	375	400
	Bt. path	+3	+3.5	0	-3	.5.5	-8.3	-11.6	15.3
4	Yards	100	235	272	300	325	350	375	400
	Bt. path	+3	0	-3	-6	-9.2	-12.9	17.2	22.1
5	Yards	100	175	310	352	375	400	425	450
	Bt. path	+3	+4.1	0	-3	-5.1	-7.7	-10.6	-13.9
6	Yards	100	175	300	341	375	400	425	450
	Bt. path	+3	+3.9	0	-3	-6.2	8.9	-12.1	-15.6
7	Yards	100	160	284	325	350	375	400	425
	Bt. path	+3	+3.8	0	-3	-5.3	-8	-11	-14.5
8	Yards	100	160	286	327	350	375	400	425
	Bt. path	+3	+3.8	0	-3	-5.1	-7.7	-10.1	-14.1
9	Yards	100	150	257	296	325	350	375	400
	Bt. path	+3	+3.5	0	-3	5.9	8.9	12.3	16.2
10	Yards	100	150	258	298	325	350	375	400
	Bt. path	+3	+3.5	0	-3	-5.5	-8.3	-11.5	-15

 

No	At yards	10mphXwind	Velocity	Ft-lb’s
1	300	6.2	2562	2186
2	300	5.6	2545	2588
3	300	6.3	2319	2148
4	300	8.5	2060	1884
5	300	5.7	2652	2341
6	300	5.6	2591	2459
7	300	5.5	2509	2487
8	300	5.2	2534	2566
9	300	6.8	2274	2297
10	300	4.7	2390	2637

 
 
 
 

	Imperial	Metric
A	.532	13.5
B	.513	13.03
C	25 deg
D	.498	12.5
E	.340	8.6
F	2.196	55.8
G	.264	6.7
H	2.620	66.5
Max Case	2.620	66.5
Trim length	2.610	66.3

 
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