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> Best .257" bullet for low velocity impacts?
Best .257" bullet for low velocity impacts?
@ 02:09 pm (GMT) |
Jason MyersDoes anybody have any input about terminal performance of .257" bullets for medium game (mostly deer 50 - 100 kg)? I'm leaving out the cartridge and range to focus solely on what a particular bullet can do at the expected terminal velocity.I'd like a bullet that will kill quickly (relatively, considering the energy available) and reliably, while consistently providing an exit wound to assist in trailing without causing excessive meat damage. Here are the options I've discovered, listed from slowest to fastest, with rough expectations of terminal velocity generated by a ballistics calculator. There isn't a whole lot of variation in velocity, so I'm mostly asking for experiences and opinions about these bullets' design and construction: 117 grain Hornady Interlock Round Nose: 2100-1750 fps 120 grain Speer Grand Slam: 2100-1850 120 grain Hornady Interlock HP: 2100-1900 120 grain Nosler Partition: 2100-1900 120 grain Swift A-Frame: 2100-1900 115 grain Barnes TSX Flat Base: 2150-1900 117 grain Hornady Interlock BT Spire Point: 2150-1950 117 grain Hornady SST: 2150-1950 115 grain Nosler Partition: 2150-1950 117 grain Sierra Game King Boattail: 2150-1950 120 grain Speer Hot Cor: 2150-1950 120 grain Speer Boat Tail: 2150-1950 120 grain Speer DeepCurl: 2150-1950 115 grain Nosler Ballistic Tip: 2200-2000 115 grain Berger Match Hunting VLD: 2200-2000 I appreciate any input you might have! |
Replies
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@ 03:18 pm (GMT) |
Nathan FosterRe: Best .257" bullet for low velocity impacts?Hi Jason, the problem you are faced with is that you want exit wounding potential on 100kg game but also want fast killing at low velocities. To achieve fast killing at low velocities, you need a fragmentary bullet. To achieve exit wounding, you need a controlled expanding bullet or a much heavier frangible bullet (around 180 grains or heavier).You also want fast killing with minimum meat damage. This is a contradiction because the more damage the bullet does, the faster the kill. Due to the generally low BC's of .25 caliber bullets, one of the greatest problems I see in the field is excessive wind drift. In plain terms, gut shots are common when the .25's are used at long ranges. The trouble is, even when using a frangible .25 caliber bullet, these projectiles do not have enough wounding potential to slow down or anchor game sufficiently for follow up shots. If gut shots are to be avoided and using the .25-06 as an example, 400 yards is a practical maximum range on days where wind is apparent. The .257 Weatherby can extend this range but it does not solve the problem of full penetration versus the frangible wounding that is required at low veloicty. Please read the part 1 game killing section of the knowledge base for more detailed info on this. Ultimately, if there was one bullet on your list capable of meeting your criteria out to 400 yards, it would be the 115gr Partition. But I cannot guarantee exit wounding in a 100% reliable fashion. The Partition has a somewhat frangible front core, a soldid shank and throughout the calibers, works well down to 1800fps. The SST works well down to 1600fps and was designed in a different manner to other caliber SST bullets. It has a flat base to aid jacket core retention. The 117gr SST is 50% frangible, retaining around 50% of its jacket and core. This is a very violent, fast killing bullet. The weakness of both the partition and SST in .25 caliber is a low BC, quickly shedding velocity and suffering wind drift at longer ranges. The Speer BTSP will shoot with less drift but is fully frangible, Matrix have a new VLD bullet for the .25 which will extend usable ranges, again fully frangible but with the potential (in my estimation) to be effective on medium game out to around 650 yards. There is no magic pill for the .25 bore. It is a small bore and and such, has its limitations. The 6.5mm bore is just a hair follicle wider but due to the 140 grain bullet designs and standard twist rates, yields greater wounding capacity at ranges of around 650 yards. But even this does not meet your criteria of wanting both exit wounding and fast killing (frangible wounding) at low velocities. The 30 cal 208gr A-max meets this criteria- but does not meet your criteria for minimum meat damage. The .25 calibers are tricky. The hot .25's kill like lightning when the right bullet is matched to the right game. But if the ranges are pushed too far, performance literally goes from one extreme to the other. It is therefore best to consider ranges. If you do not own a .25 and want to shoot to 650 yards or more- the answer is fairly simple, buy a heavier caliber. if you own a .25 cal, consider a max range of around 400 yards for the .25-06 and around 500 yards for the .257 Weatherby. You may want to try your hand at shooting past these ranges, that is up to you. The ranges I am quoting are based on field experience, seeing the effects of wind drift versus wounding and the difficulty of both avoiding and or overcoming errors and limitations. |
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@ 05:02 pm (GMT) |
Jason MyersRe: Best .257" bullet for low velocity impacts?Thank you Mr. Foster!I have read your article about game killing with great interest. It was very educational. He helped me to frame this whole question in the first place. I do understand that I'm asking a question that is threading the needle of near-impossibility. I'll fill you in about the exact application. I'm not doing long-range hunting, but rather, hunting with a cartridge with relatively low energy for deer hunting, the .25-35 Winchester. It has often been described as the lowest-recoil round you can effectively use for deer hunting (though that was before very high velocity small bore rifles were available). The velocities I estimated above are what I'd estimate the bullets to be traveling at around 60-75 yards (maximum) and at 150-160 yards (minimum). They are influenced by the ballistic coefficient and a slight muzzle-velocity fudge factor for bullets lighter or heavier than 117 gr. The vast majority of my hunting is within 50 yards, and I would never attempt a shot at big game greater than 150 yards with this rifle. My goal is to improve my confidence with the round at the "long" ranges for this cartridge, being around 100 yards. When considering terminal ballistics, I figure that my low muzzle velocity (~2300 fps) is analogous to hunting at long ranges. The only currently available bullet normally used in handloading the .25-35 is the 117 Hornady RN. I've so far only used similar factory ammo for hunting, but many people are happy with the bullet out even as far as 200 yards. Being a round nose bullet, the disadvantage of the nose in exterior ballistics is seen by some to be an advantage for terminal ballistics. I'm considering using a higher BC bullet in the chamber in order to have higher velocity at range, if the bullet appropriately transfers the energy. I know of an individual that uses a 100 gr fragmenting bullet in the 25-35 for deer hunting with a muzzle velocity ~2500 fps). He is happy with it, but doesn't consistently get exit wounds and the deer subspecies he hunts are smaller than the ones I hunt. He also uses a semi-spitzer hollow point in a tubular magazine. I plan on keeping the RN bullets in the magazine and don't want to almost match that load's trajectory out to 100 yards. I should clarify that what I'm looking to do is improve relative to a known (the 117 Hornady RN). Can I improve by keeping a few hundred fps with a different bullet? I realize that faster killing might not be fast compared to a heavier cartridge. I appreciate your review of the the SST and the Partition in .257. Do you have any opinions on the Nosler Ballistic Tip with lower impact velocities (2000-2200 fps)? It looks like a good option on paper. |
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@ 05:11 pm (GMT) |
Nathan FosterRe: Best .257" bullet for low velocity impacts?That is an interesting dilemma.When I look back on various bullet testing over the years, I can think of many examples where exchanging controlled expanding bullet designs has made very little difference at lower velocities. In some instances, changing from the Interlock to the more frangible/non controlled GameKing and Ballistic Tip made no noticeable differences due to the muzzle velocities or impact velocities involved. An immensely soft and fully fragmentary bullet tends to make the more dramatic increase in wounding that your are looking for. To this end, I think that to achieve your goal, you may have to sacrifice some penetration. The softest pointed fragmentary projectile available is the 120gr Speer BTSP. The jacket is much softer than the BT, though the BT is a good bullet, both in 100 and 115gr weights. This may produce the more dramatic result you are looking for, retaining enough velocity at 150 yards to produce full expansion and fragmentation. Penetration is fair and I think you will find it favorable in comparison to the 117gr RN. I would be interested in testing the 115gr partition fired backwards. But this would be an expensive exercise which could quite possibly prove fruitless. The goal would be to develop a load that could be used safely in the tube mag with a flat point but featuring an ultra low drag boat tail. My concern though, is that the heel crimp may come into contact with primers in the tube mag. If it worked, there is potential for a bursting effect as occurs with the flat tipped and crimped Norma Vulcan, combined with a degree of deep penetration. But like I say, an expensive and possibly fruitless exercise. When I studied the early 160gr Western .30WCF HP projectiles, I found that these where fully fragmentary (though we have to take age annealing of the projectiles into account). I pulled the old loads, reloaded them in new .30-30 brass for safety, then hunted with the HP projectiles out to 100-150 yards. The wounding was somewhat dramatic but not so dramatic as to be spectacular in any way. I believe that this was a very early attempt to increase width of wounding in a cartridge that was designed to outperform the .45-70 but was perhaps not delivering quite so well on its promise with the original soft point load. Its just a theory though. Please keep us updated on your progress and please keep your camera handy. |
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@ 01:07 pm (GMT) |
Jason MyersRe: Best .257" bullet for low velocity impacts?Thank you for your helpful information. I will keep you and your readers updated, though this is a long-term project, and it may be over a year before I have much of value to share.Quote: To this end, I think that to achieve your goal, you may have to sacrifice some penetration.
I understand this. I'm asking the question to avoid sacrificing too much penetration. As I mentioned before, I know of somebody who loads 100 gr. Speer Varmint HP at a bit over 2500 fps for deer hunting. They kill but don't usually exit. That is not what I want, especially considering larger deer that I often hunt. My understanding of terminal ballistics leads me to believe that my ideal is a bullet that expands slow enough initially to avoid extensive meat damage at entry, then expands rapidly inside the chest cavity, and has expended most of its energy and accomplished most of its expansion by the time the bullet reaches the other side, making a exit wound that is as small as possible but still consistently allows the bullet to exit. To be clear, I'm talking about broadside shots to the rear of the shoulders/lung area. I would never expect a longitudinal shot with this cartridge to exit. Similarly, I don't expect that a shot through both shoulders will consistently exit larger deer with a more fragmentary bullet. My understanding of what the 117 Hornady RN does in the 25-35 is that expansion is initiated pretty rapidly, due to the blunt meplat. Expansion is pretty controlled though the animal, due to the low velocity (the same bullet is also used in the 257 Weatherby Magnum at ~3200 fps). Penetration is good due to the high SD and construction of the bullet; the bullet kills consistently, but wounding is not concentrated as much in vital organs as I believe may be possible. Because of the low BC (.243), velocity is shed pretty rapidly, providing less available energy for both penetration and expansion at longer ranges. Under 50 yards there isn't a lot of difference, but at 125 yards, the RN has 20% less energy than a BT fired at the same MV. To summarize your feedback and other impressions I've gotten: 117 grain Hornady Interlock Round Nose: 2100-1750 fps - (Baseline) 120 grain Speer Grand Slam: 2100-1850 - Too tough for deer at low velocities 120 grain Hornady Interlock HP: 2100-1900 - Still unknown, probably not to different from 117 Interlock BTSP 120 grain Nosler Partition: 2100-1900 - Too heavy (slow), consider 115 Partition 120 grain Swift A-Frame: 2100-1900 - Too tough for deer at low velocities 115 grain Barnes TSX Flat Base: 2150-1900 - Too tough for deer at low velocities 117 grain Hornady Interlock BT Spire Point: 2150-1950 - Still unknown, seems to me to be a good counterpart to the RN, but may not offer much benefit 117 grain Hornady SST: 2150-1950 - Good option (note that my last buck was shot with a 12 ga SST sabot 115 grain Nosler Partition: 2150-1950 - Good possibility, design facilitates penetration, may not have as much expansion as ideal 117 grain Sierra Game King Boattail: 2150-1950 - Very similar to Nosler Ballistic Tip, but with slightly lower BC (I also realize that I missed the 120 grain Sierra Game King Hollow Point Boat Tail) 120 grain Speer Hot Cor: 2150-1950 - Still unknown 120 grain Speer Boat Tail: 2150-1950 - Good option, very frangible, but with higher SD may have better penetration that similar 115 gr bullets 120 grain Speer DeepCurl: 2150-1950 - Still unknown 115 grain Nosler Ballistic Tip: 2200-2000 - Good option, not as frangible as the Speer, but has slightly higher velocity due to lower mass 115 grain Berger Match Hunting VLD: 2200-2000 - Still unknown One follow-up question from your first response: Quote: The 6.5mm bore is just a hair follicle wider but due to the 140 grain bullet designs and standard twist rates
Are you talking about twist rates as a factor in terminal ballistics, or only in accuracy? I don't remember seeing anything in "Part 1 Game Killing" about bullet rotation. This rifle has 1 in 8" twist, designed to stabilize long bullets at low velocities. I believe that 1 in 8" was set early in the life of the rifle and cartridge (1890s), when muzzle velocities were not as high as were achieved a few decades later. The miller stability factor of current factory ammo is above 3. There is enough twist to stabilize the longer bullets above (factors of ~1.5-1.7). If greater bullet rotation leads to greater wounding (as I can imagine it might by facilitating expansion through centrifugal force), then my bullets are rotation at about 3450 rps, similar to but a bit faster than what a 1 in 12" 257 Weatherby would achieve and similar to a 1 in 10" 257 Roberts. |
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@ 08:52 pm (GMT) |
Nathan FosterRe: Best .257" bullet for low velocity impacts?Wow, thats one heck of a twist rate, would stabilize a 160 grain bullet.My comments about the 6.5 twist were regarding its ability to stabilize and drive a heavy bullet- the heavy bullet weight and A-Max design delivering greater wounding and killing power. I don't put much stock in rotational forces with regards to increased twist rate resulting in increased wounding. I am sure that extra twist does induce greater wounding, both in theory and in practice. But in the field, I have not been able to ascertain any noticeable difference in wound channel diameters. Of all of the wounding variables, twist rate has been the least vivid. I remember when 1:8 and 1:8.5 twists came out for the 7mm caliber. Word was that these twist rates would cause game to be vaporized. Unfortunately, the only thing that was vaporized in the magnums was the bullets- usually before they hit their target. Hence Berger having to toughen up their bullets- which of course created the opposite effect of what was originally postulated regarding the fast twist 7mm bores. In time we will have a few 190gr 7mm bullets on the market. These bullets can still be stabilized with a 1:9 twist. Anyway, getting back to your subject. You mentioned two more bullets, the Gameking HPBT and 120 grain Interlock HP. Both are good bullets, frangible like the Speer. Both have merit for your application so you have three or four bullets to chose from, the Speer BTSP, GK HPBT and Interlock HP. The 117gr SST is also a very good bullet and worth considering as you have mentioned. The Interlock HPBT has seen a recent change, when I initially tested it, it did not have a cannelure and was fully frangible. The newer bullet has a cannelure to arrest fragmentation but its effect is very limited. Shot placement is a big issue and its also a cultural thing as well as being affected by trends. In NZ for many decades, hunters aimed for the point of the shoulder. After the .222 hit the scene, besides neck shots, hind shoulder shots became a common POA. In the U.S, the hind shoulder shot has been the norm since Adam was a cowboy. These cultural and trend variations have a pronounced effect on results. If you look at the .243 section, you will see that I state that the .243 is effective on quite large bodied deer with the forwards shoulder shot. This occurs out of a mixture of several factors such as the use of slower 100gr bullets, that 100 grain .243 bullets lose velocity quickly and can therefore achieve a measure of penetration- combined with the shoulder bones promoting wide wounding and so the list goes on. It is from this that we see such iconic figures (in NZ) as writer/culler Phillip Holden (rest in peace our friend) dropping Wapiti and Red deer without problems. What we often fail to understand (and I don't think Phillip realized this) was that the man was a crack shot, I mean a real crack shot from any position and in any wind out to 400 yards or so. If we put this into perspective for you, a suitable bullet striking the autonomous plexus 1" forwards of the line of the leg (through the scapula ball joint) will cause instant poleaxe and death. Of course if you are using open sights, this can be hard to achieve at 120 yards. In contrast, your friend is using a varmint bullet, rear lung shots, obtaining maximum wounding. The 250-3000 was employed pretty much in an identical manner and used out to ranges which duplicate your friend's bullet impact velocities and shot placement. By the same token, the cartridge and its fast expanding low SD bullets fell by the wayside on larger deer species for the same reasons you are concerned about. Ultimately, there is more to this than selecting an optimum bullet. Shot placement will also dictate speed of killing. If an appropriate level of accuracy can be achieved, the forward shoulder shot will increase speed of killing. But at the same time, forward shoulder shots cause greater meat damage. These are all factors you will have to consider and weigh. You mentioned that your friend was loading HP bullets in his tube magazine. I have to admit, I would rather, if he is going to pursue the dangerous practice of loading pointed bullets in tube mags, use a Speer BTSP as the lead of the Speer is very soft. Just a thought anyway. It would at the very least give you a wider range of results if he adopted the Speer for a season while you adopted something else of your choosing. |
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@ 10:06 am (GMT) |
Jason MyersRe: Best .257" bullet for low velocity impacts?Quote: Wow, thats one heck of a twist rate, would stabilize a 160 grain bullet.
Remember that I'm dealing with a ~2300 fps muzzle velocity. I believe the 1 in 8" was determined when the expected MV was around 1800-2000 fps. When developments in steel and smokeless powder quickly increased the limits, the rate stuck. Other rifles chambered for the cartridge and similar cartridges, like the .25 Remington or 25.36 Marlin, usually have a slightly slower twist. Quote: You mentioned that your friend was loading HP bullets in his tube magazine. I have to admit, I would rather, if he is going to pursue the dangerous practice of loading pointed bullets in tube mags, use a Speer BTSP as the lead of the Speer is very soft. Just a thought anyway. It would at the very least give you a wider range of results if he adopted the Speer for a season while you adopted something else of your choosing.
This is the bullet he uses: http://www.speer-bullets.com/ballistics/detail.aspx?id=27 I think one of the reasons that he feels safer (and so far so good), is that the bullet has a pretty wide tip compared to most spitzers. (Though I should note that I only know him through internet forums.) He seems pretty happy with it, and believes the way to go with the 25-35 is a frangible bullet of 100 grains at a MV ~2500 fps. I'm insisting on 115+ grains for a couple of reasons. Thanks again for your input! |
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@ 02:35 pm (GMT) |
Nathan FosterRe: Best .257" bullet for low velocity impacts?No worries Jason, I find what you and your friend/correspondent are doing to be very interesting, including using the HP Speer bullets in the tube magazine. |
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@ 09:47 pm (GMT) |
Jason MyersRe: Best .257" bullet for low velocity impacts?I had shied away from considering 100 gr. bullets because I didn't think I'd get the penetration I want. The point of aim should be different enough from the 117 rn at short ranges to be a concern. Now I wonder if a 100 gr. nosler partition would be a good option.Compared to a 115-120 grain bullet we've already discussed at a MV around 2300 fps slowing to around 1850-2000 fps a bit after 150 yards (depending on the bullet), what about a 100 gr. NP at about 2500 fps staying above 2100 fps until well after 150 yards? I really like the design theory behind the partition, but everything I've read points to the low velocities mentioned in my original post being too slow for good terminal performance. |
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@ 09:47 pm (GMT) |
Jason MyersRe: Best .257" bullet for low velocity impacts?I had shied away from considering 100 gr. bullets because I didn't think I'd get the penetration I want. The point of aim should be different enough from the 117 rn at short ranges to be a concern. Now I wonder if a 100 gr. nosler partition would be a good option.Compared to a 115-120 grain bullet we've already discussed at a MV around 2300 fps slowing to around 1850-2000 fps a bit after 150 yards (depending on the bullet), what about a 100 gr. NP at about 2500 fps staying above 2100 fps until well after 150 yards? I really like the design theory behind the partition, but everything I've read points to the low velocities mentioned in my original post being too slow for good terminal performance. |
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@ 03:38 pm (GMT) |
Nathan FosterRe: Best .257" bullet for low velocity impacts?That has merit Jason. One of the unique aspects of the Partition is that after expansion (complete loss of the front core), the rear core maintains quite high velocity. This often causes trauma at a much deeper level than occurs with other bullet designs. So while we may envisage the Partition as being a heavily controlled expanding bullet with limited wounding capacity (in comparison to a fully fragmentary bullet), the results can be quite the opposite. Where before a smaller bore may have appeared marginal and game stand or run after the shot, the Partition used to take the same shot can show an immediate and noticeable difference, producing what could best be described as an 'emphatic' kill.By the way, one of my guys got out yesterday and shot a billy goat with a 6.5 partition, downloaded, bullet fired backwards. Goat was shot from above, impact around 2000fps, down into the back strap, entry wound through ribs was 2", liver destroyed, bullet passed through rumen, exited animal. Fast killing, highly traumatic. |
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@ 11:05 pm (GMT) |
Richard HRe: Best .257" bullet for low velocity impacts?I have been reading these posts with interest. I am guessing that these same bullets for low impact velocities will help extend the range of a 257 Roberts or 25-06.In particular that 100 grain Partition, 120 grain Speer boat tail, and 117 grain SST look attractive. The Partition is particularly attractive to me since I also shoot hogs (usually at about 80-125 yds). Deer are usually harvested at less than 200 yds, but I want to get into some longer range shooting. I would prefer to try to get an accurate load for most game and not have to switch out bullets a lot (and fiddle with my scope zeros). Thanks for the posts. |
@ 09:59 pm (GMT) |
William FluitRe: Best .257" bullet for low velocity impacts?We have several older gentlemen that're long time customers who are AVID users of the 250-3000 cartridge. They've been using the 250 Savage for 20-40 years. They all swear by the Sierra GameKing 90 grain and nothing else. They all live and hunt in open country where there is nothing to block your view of the horizon.I have a .25 WSSM and a wildcat 25-223. But have shot any game with either cartridge yet. |
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