.325 Winchester Short Magnum

History

 
Following the introduction of the .300 Winchester Short Magnum (.300WSM) in 2000, hunters waited expectantly for Winchester to produce a full family of short magnum cartridges based on the .404 Jeffery case design. In 2001 Winchester released the .270 and 7mm WSM cartridges. 2002 saw the release of the .223 and .243 WSSM Super Short Magnums and in 2003 Winchester released the .25WSSM.
 
After three years waiting, Winchester had yet to introduce a medium bore WSM. By this time many wildcatters were already exploring the possibilities of the .300WSM case necked up to .338 with some hunters equally enthusiastic about a .358. To the surprise of all, Winchester released the .325WSM based on the .300WSM case necked up to 8mm, announced in a press release during December 2004 as being Winchester’s new cartridge for 2005.
 
Although Winchester engineers had hoped to release a .338WSM the long .338 bullets did not complement the WSM design. Winchester had already altered the magazines of their short action rifles for the WSM cartridges, the magazines being essentially medium length ( 2.990” for Browning rifles and 3.031” for Winchester rifles). Yet even with these modifications, the long .338 projectiles encroached on powder space, particularly with 250 grain bullets. Ultimately, the prototype .338 WSM proved ineffective, generating velocities 100fps less than the .338 Winchester Magnum. The .338 did not achieve the criteria required of the WSM’s which were designed to match the performance of existing magnums in short action rifles. Due to the expectations of hunters and the ongoing demand for a heavy WSM cartridge for use on large North American game, Winchester engineers began to experiment with an 8mm (.323”) cartridge. The move to the 8mm bore diameter helped optimize performance of the WSM case which performed well when loaded with heavier 200 grain bullets, boasting velocities of 2950fps.  
 
The .325 WSM was received with mixed results. For many, the .325 WSM was a cop out. The .325 WSM fired the same bullet weights as the .300 WSM, albeit with lower BC bullets. Furthermore, those who built wildcat .338” and .358” (.35 Sambar) cartridges based on the .300 WSM case felt that their wildcat cartridges were potent in their own right, regardless of whether they duplicated or bested existing magnums. The .325 WSM was often promoted as having greater frontal area than the .300 WSM while having higher sectional densities and velocities than the .338 Winchester Magnum - the perfect big game cartridge, none of which held any serious weight.
 
In contrast to its negative reception, many hunters purchased .325 WSM rifles, some bought into the hype, others purchased rifles following more careful consideration. The .325 WSM cartridge was generally adopted by hunters targeting large bodied medium game and to their delight, regardless of the pros and cons of the .325 WSM design, the short magnum worked. Having gained a small foothold, the .325 WSM has retained a mild following ever since. Those who use it like it.
 
One of the most positive outcomes of the introduction of the .325 WSM is the re-invigoration of interest in the 8mm bore in general. The .325 WSM has inspired new bullet designs from major manufacturers which can be employed in the both the .325 WSM and traditional 8mm cartridges. The .325 WSM has therefore been highly beneficial in ensuring the continued popularity of the classic 8mm bore.
 

Performance 

 
The .325 WSM is peculiar in that hunters generally view this cartridge as being one that fires 200 grain bullets as if the .300 WSM was not capable of doing so, as if there was no such thing as a 200 grain .30 caliber bullet which is of course far from being true. But on closer inspection the answer as to why the .325 WSM is often viewed in this way becomes apparent. Factory .300WSM ammunition typically features 150 to 180 grain ammunition as a standard off the shelf item while .325 WSM factory ammunition is available in 180 to 220 grain weights. To this end the .325 WSM has great potential for factory ammunition users targeting Elk sized game. Further to this, not only does the .325 utilize 200 grain bullets as standard fodder, it also does an immensely good job with this bullet weight, the slight reduction in SD’s in comparison to the .30 caliber bore having the potential to initiate greater trauma when matched to ideal game body weights.
 
The .325WSM meets the needs of the mountain hunter requiring a rifle of minimum bulk and weight, capable of firing heavy projectiles at high velocities for use on game weighing anywhere between 90 and 450kg (198-1000lb). Bullet diameter of the 8mm caliber is only 5% greater (10% more frontal area) than the .300 caliber and when using heavy weight bullets of equal construction there is no visible difference between the two when comparing wound channels. But at a more subtle level, increased energy transfer can be utilized to initiate increased speed of killing. But again, this is very subtle.
 
For factory ammunition users the .325WSM loaded with 200 to 220 grain bullets delivers high shock for fast killing of large game out to ranges of around 150 yards and clean but often delayed killing out to ranges of around 300 yards with rear lung shots. The .325 WSM  can be sighted to shoot flat out to ranges exceeding 325 yards and retains 2000ftlbs energy out to a range of 500 yards, the oft quoted minimum energy level required to cleanly kill large game. That said, bullet construction has a far greater influence on speed of killing. Nevertheless, Winchester’s 180 grain Ballistic Tip and 220 grain PowerPoint loads are both capable of cleanly killing game at ranges of up to 500 yards with select placement.
 
The .325 can in some instances deliver hydrostatic shock (keep projectiles above 2600fps) out to greater ranges than factory .338 Winchester Magnum ammunition while factory loads for the .325 WSM are most definitely heavier than .300WSM offerings and at a subtle level, can generate more trauma than like weight .30 caliber bullets. Each of these factors amount to excellent performance when the .325 WSM and its ammunition are matched to appropriate game weights. That said, it would be very unwise to state that the .325 WSM is in any superior to the .30 and .338 bores. The subtleties of each factor are so fine that few hunters would ever notice the almost imperceptible differences between the .300 WSM and .325 WSM. It simply is what it is - the .325 WSM showing its greatest strengths when employed by hunters reliant on factory ammunition.
 
Of its negative qualities, the .325 WSM loaded with factory ammunition is not ideally suited for use on game weighing below 90kg (198lb). Internal wounding on light or lean game is generally excellent however rear lung shots invariably produce delayed killing - a concern for those who hunt in heavy timber or dangerous mountain terrain where game recovery may be difficult. Fortunately these problems can be avoided by utilizing hand loads. A second negative factor concerning the .325 WSM is the lack of any true premium factory loads for dangerous game such as large bodied Brown bear. A third negative aspect of the .325 WSM is its low BC’s in comparison to .30 and .338 caliber bullet designs with regard to long range hunting. To some extent this is gradually being rectified thanks to new 8mm bullet designs. As always, expectations are a key factor. Those who wish to shoot to truly long ranges may very well prefer to adopt a more dedicated long range cartridge or projectile design. Those who wish to hunt potentially dangerous game have the option of hand loading premium Nosler Partition, Swift or Woodleigh bullets. In its most basic form, the .325 WSM is a 450kg / 450 yard cartridge available in compact rifle platforms. Both game weights and ranges can be increased with carefully chosen hand loaded projectiles and optimum shot placement.

   

Factory Ammunition

Winchester currently produce three factory loads for the .325WSM. These include the 180 grain Ballistic SilverTip (Nosler Ballistic Tip) loaded to a true 3060fps, the 200 grain Accubond loaded to a true 2950fps and the 220 grain PowerPoint bullet loaded to 2840fps.
 
The 180 grain BST is suited to open country hunting of game weighing between 90 and 200kg (198-396lb) with Elk weighing up to 320kg (700lb) as an upper limit. As ranges are increased beyond 200 yards, so too does the penetration potential on Elk sized game. Wound channels are directly comparable to the .300’s loaded with the Nosler Ballistic Tip and Sierra GameKing 180 grain projectiles. The Ballistic Tip is highly frangible at very close ranges, placing limitations on penetration - yet altogether too stout for dedicated long range shooting. Nevertheless, this bullet is right at home when used on large bodied deer (Mule / Red) at ranges of up to 450 yards. Within these ranges and when matched appropriately to game body weights, the BST is capable of producing outstanding performance. A maximum range of around 650 yards is the absolute limit for the BST, requiring extremely careful shot placement and a mastery of wind drift at such ranges.
 
The 200 grain Accubond is a versatile bullet suitable for a wide variety of game weighing between 90 and 320kg (198-700lb). This bullet does have a tendency to lose an excessive amount of weight when striking heavy muscle and bone at close ranges - a factor to consider when hunting large bodied game including the potentially dangerous Brown bear. The Accubond is also not particularly well suited to the heavy ball joints encountered on moose sized game in the 450kg (1000lb) range. On game of this size the Accubond is adequate for meat saver and quartering away shots but hunters should avoid purposefully attempting to break shoulder bones. Since the introduction of the .325 WSM, the 200 grain Winchester Accubond load has been used by a vast number of U.S .325 WSM users as a general all round load with great success. The typical meat saver shot employed by U.S hunters is a factor that has ensured adequate and often excellent penetration. At Magnum velocities, both the Ballistic Tip and Accubond can also display increased trauma in comparison to .30 caliber counterparts which can help aid flexibility, particularly the speed of killing when hunting lean game. But as previously described, the differences can be very subtle (especially in comparison to the now obsolete .338 caliber 180 grain Ballistic Tip).  
 
The 220 grain PowerPoint bullet is a very soft, partially (sometimes fully) frangible bullet design. This style of design harkens back to a time when heavy but soft bullets were used to great effect on medium game, offering very broad wounding, this concept also being a critical factor in successful long range bullet design. From a muzzle velocity of 2840fps, the 220 grain PowerPoint cannot produce hydrostatic shock much beyond woods ranges but with optimum target resistance is capable of rendering immensely broad internal wounding for fast killing out to ranges of around 300 yards. The PowerPoint bullet is ideal for game in the 90 to 320kg (200-700lb) range but should not be relied on to break and penetrate beyond heavy bone on larger animals. This bullet can be used for scapular and meat saver shots on Moose weighing up to 450kg (1000lb) but like the Accubond, this is the absolute limit for this bullet design.
 

Hand Loading

The .325 WSM is the smallest of the WSM family. While the case length remains the same as its kin, the shoulder is set back 1.8mm or .074". It is possible to utilize .300 WSM cases as the basis for forming .325 brass, however the process requires a degree of hefty forming to obtain the desirable shoulder length reduction. Fortunately .325 WSM is readily available while factory ammunition can also be used as a source of brass for hand loading.

Like all of the WSM’s it is hard to improve on the velocities of the .325WSM with hand loaded ammunition. The .325WSM achieves optimum results when loaded with medium-slow burners in the H4350 (ADI 2209) range. Top velocities for the .325WSM are 3350fps with 150 grain bullets, 3050fps with 180 grain bullets, 2950fps with 200 grain bullets and up to 2850fps with 220 grain bullets. Unfortunately, attempting to duplicate Winchester loads can be extremely hard on case life due to the fact that Winchester WSM ammunition is generally loaded to maximum pressures. This along with the recoil produced in light weight rifles can often dictate that better accuracy and case life occur some 50-100fps below the figures quoted here. Hand loaders are therefore cautioned to view the velocities stated here as the upper limits for the .325 WSM.
The .325 WSM is not a long throated cartridge design, allowing projectiles to be seated close to the rifling lands providing suitable WSM length magazine boxes are employed.
 
Having covered 8mm bullet performance in the 8x57 JS, 8mm-06, 8x 68 S and 8mm Remington Magnum texts, there is no need to reiterate performance within this text. The .325 WSM is very much on par with the 8x68 S. It is however worth covering basic concepts to drive home bullet selection factors.
 
For game weighing between 40 and 80kg  (88-176lb) the .325WSM gives fast killing out to 220 yards and clean kills out to all practical ranges when loaded with the 150 grain projectiles produced by Hornady, Sierra and Speer. All are prone to bullet blow up at close ranges but all produce adequate penetration on light or lean bodied game. Results are emphatic out to ranges of around 250 yards, continuing to produce clean but sometimes delayed killing thereafter. Both the Speer and Sierra bullets have effective ranges of around 400 yards, producing slow killing thereafter. The Hornady Interlock is effective to ranges of 550 to 600 yards however wind drift is severe at such ranges.
 
The new Hornady SST should hopefully make for an extremely good all round bullet for sheep, goat, boar and deer weighing up to 150kg (330lb) and will hopefully be able to tackle larger body weights at extended ranges. Predicted effective range is around 800 yards.
 
Traditional 170 to 180 grain U.S made 8mm projectiles generally suit game in the 90 to 320kg range (200-700lb) with 320kg (700lb) as an upper limit. The 170 grain Speer Hotcor and 175 grain Sierra Prohunter are capable of handling lightly raking shots on game of this size and in the .325WSM give fast kills out to 175 yards. The 180 grain Nolser Ballistic Tip as mentioned in the factory ammunition section is ideal for Mule and Red deer along with other deer and antelope species of this size.
 
Heavy 200 grain bullets generally suit game weighing between 90 and 450kg (200-1000lb). It should be noted that traditional 170 to 180 grain U.S made projectiles are also best suited to game weighing over 90kg regarding speed of killing, the difference being that heavier 200 grain bullets yielding high SD’s can deliver greater penetration. To this end, in some instances, a 200 grain bullet can prove to be extremely useful as an all round load for mid weight game through to large deer species. That said, bullet construction must be matched to the job at hand. Typical bullet options include the 195 grain Hornady Interlock (very soft), the 200 grain Speer Hotcor (an excellent budget moderate range bullet), the 200 grain Nosler Partition (an excellent all rounder) followed by the deep penetrating Woodleigh and Swift bullet designs. For long range work on large bodied deer, the Hornady 196 grain match bullet can be modified to produce fragmentation at extended ranges.
 
Heavy 220 to 250 grain bullets are generally best suited to very large and tough bodied medium game while premium bullet designs can be used on heavy game with select shot placement. The 220 grain Sierra BTSP has in the past caused considerable confusion among hunters. This bullet features an extra thick jacket (like its 250 grain .338 counterpart) to aid penetration however it must be understood that this is not a controlled expanding bullet design. The core is not locked into the jacket in any way while the ogive lacks any skives (notches) to control bullet forntal area. Where one hunters achieves complete success on Grizzly bear, another finds himself using multiple shots to anchor the same game. Range, impact velocity and shot placement all play a part in this process. Pushed hard and fast into heavy muscle and bone, the Sierra is fully frangible. At mid ranges, the Sierra produces a mixture of expansion and fragmentation on Elk sized game, producing excellent wounding characteristics. As ranges are extended and velocity falls below 2200fps, the thick jacket of the Sierra prevents wide wounding, the bullet becoming highly reliant on target resistance as a means to initiate expansion. And so we have a bullet which is sometimes too frangible at close ranges and too stout for long range work. The trick is to match this bullet to appropriate game and ranges. The Sierra 220 gran GameKing is an excellent bullet when used accordingly.
 
Heavy premium Woodleigh and Swift 8mm bullets are at their best when used on large bodied game at close to moderate ranges where velocity and therefore trauma are very high. As velocity falls away, so too does disproportionate to caliber wounding, limiting the performance of the 8mm bore on heavy body weights. And while it is true that low impact velocities can help aid penetration, both the Woodleigh and Swift bullet designs perform exceptionally well at high velocities, striking the balance between wide wounding and deep penetration.
 
Readers are also highly encouraged to experiment with Norma and RWS bullet designs. When used out to moderate ranges, these bullet designs can wring the full potential out of the 8mm bore, producing emphatic killing and excellent game weight flexibility.
 

Closing Comments

 
The future of the .325WSM will perhaps duplicate that of the 8mm Remington Magnum. At this time of writing (2014), Winchester are still offering the .325 WSM as a chambering for their Model 70 Extreme rifle. Other manufacturers have adopted the .270, 7mm and .300 WSM chamberings but have shown little interest in the 8mm chambering.
 
In its ideal role the .325 WSM suits foot hunters who traverse vast distances to secure larger bodied medium game utilizing heavy bullets. This cartridge is optimally suited to factory ammunition users who require access to heavy bullet weights for Elk and similar sized game. The current Winchester WSM rifle design is of a moderate weight, producing substantial but tolerable recoil and often exceptional accuracy with practice. The compact nature is ideal for back pack hunting.
 
Many hunters and shooting authorities have slammed the .325 WSM as a cop out, a plan B, a product that was not needed because the .30 and .338 bores already covered the same ground, a product that was marketed all the same in order to increase profits. All of this is true. However one great virtue of the .325 WSM is that it has helped maintain interest in the classic 8mm bore, paving the way for new bullet designs to the benefit of all.  
 
 

Suggested loads: .325 WSM					Barrel length: 24”
No	ID		Sectional Density	Ballistic Coefficient	Observed  MV Fps	ME Ft-lb’s
1	FL	Winchester 180gr BST	.246	.439	3060	3742
2	FL	Winchester 200gr AB	.274	.477	2950	3864
3	HL	Winchester 220gr PP	.301	.388	2840	3939
4	HL	200gr Partition	.274	.350	2950	3864
5	HL	220gr Woodleigh RN 64C	.301	.355	2750	3694

 

Suggested sight settings and bullet paths
1	Yards	100	150	279	320	350	375	400
	Bt. path	+3	+3.7	0	-3	-6	-8.8	-12.1
2	Yards	100	150	269	309	325	350	375	400
	Bt. path	+3	+3.6	0	-3	-4.5	-8.4	10.2	13.7
3	Yards	100	150	250	289	325	350	375
	Bt. path	+3	+3.5	0	-3	-7	-10.2	-14
4	Yards	100	150	258	297	325	350	375	400
	Bt. path	+3	+3.5	0	-3	-6	-9.1	-12.7	-16.8
5	Yards	100	237	274	300	325	350
	Bt. path	+3	0	-3	-5.8	-9	-12.7

 

No	At yards	10mphXwind	Velocity	Ft-lb’s
1	300	6.1	2443	2385
2	300	6.1	2383	2522
3	300	8.1	2169	2298
4	300	8.6	2195	2139
5	300	9.4	2036	2024

 

 

.325 WSM	Imperial	Metric
A	.535	13.59
B	.555	14.1
C	35 Deg
D	.538	13.67
E	.358	9.09
F	1.663	42.25
G	.370	9.4
H	2.100	53.34
Max Case	2.100	53.34
Trim length	2.090	53.04

 
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