Applied Theory

[TCLouis]

Ok, deer season is over for most of us and I am trying to get a head start on next year.

Given that a bigger boolit (diameter) is better, and a large meplat makes a boolit more effective, the larger the better.


Considering your actual results on game what is the "minimum" impact velocity for a boolit like the 311440, how about the RCBS 150 RNFPGC, or the 338X200 RNFPGC, or the "recent" .325X175, or the 35X22? GB molds?

Speculation is fine, but your field tested results are preferred.

[Bass Ackward]

Given that a bigger boolit (diameter) is better, and a large meplat makes a boolit more effective, the larger the better.

Considering your actual results on game what is the "minimum" impact velocity for a boolit like the 311440, how about the RCBS 150 RNFPGC, or the 338X200 RNFPGC, or the "recent" .325X175, or the 35X22? GB molds?


TC,

I have one problem and one question. The problem is with your meplat statement above. And it leads into the question how hard do you make your bullets?

See I find meplat size over rated on game and some cases a detriment. How I think of meplat size is how big does it need to be to start expansion at my hardness in the game of interest. After all the mental tabulation, I go to the jugs for testing.

And I will tell you it isn't always what you think. Because when you calculate for minimums, (long range) you seldom realize how you are affecting the maximums. (close in shots) And considering the common ranges that deer are shot at, the close distances are more the problem with wide meplats on smaller bores.

Only way I see to make this argument is that a guy will be wearing a handgun for close shots (75 yards) and the rifle is only for longer range. And still my advice, after a lengthy paragraph, would be to test, test, test anyway.

[RugerFan]

People talk a lot about muzzle velocity, but not so much about impact velocity. Definitely an interesting question.

A bullet impacting a deer “can” knock the animal unconscious without immediately killing it. In this scenario, if bullet placement is optimum (chest cavity), the deer will bleed to death rather quickly and not regain consciousness.

What is the minimum velocity for this “shock value”? Good question. Is “bam flop” your goal or is deep penetration more important?

BA is correct in that experimentation is required. The answer you seek depends on your alloy, bullet style, bullet weight, distance of the shot, toughness of the animal, and probably something I’m forgetting.

If you’re shooting hard cast bullets and expansion is not expected then yes, a bigger metplat is desirable.

[Larry Gibson]

I agree with Bass. My experience in killing big game with cast bullets shot out of rifles is I prefer to have a bullet cast of maleable alloy so that it expands. I've found that this results in quicker kills rather than depenting on meplat size and a hard bullet. Asmentioned you must experiment to find the best ballance of expansion at the farthest range you will shoot and how the bullet expands at close range.

I genrally load to 2000-2200 fps with my rifle hunting bullets. With the faster twist barrels I can hold good accuracy for at least the first 5 shots out of a cold clean barrel. That is sufficient for hunting. A meplat will facilitate expansion vs a round nose and sometimes I HP the bullets to a depth of 1/3 to 1/2 the length of the bullet nose.

I use water soaked news print to test. Example; with a 308 Winchester using 311041. I will have already ran tests for velocity and accuracy. To test for expansion I shoot 2 shots of factory or factory equivelent 170 J bullets out of a M94 30-30 (this is my standard for a "good" performing deer load to 200 yards) into the wet newsprint at 25 yards. I then shoot 2 shots of the test .308 cast loads into the same wet newsprint. I then compare the expansion and penetration of the cast loads to the 30-30 J bullets. If I've found a suitable cast load that gives comparable performance at 25 yards to the J bullets I then put another bundle of wet news print out at 200 yds. I then shoot 3 shots of the same 170 gr 30-30 load and 3 shots of the selected cast load(s). If the cast bullet expands and penetrates in good comparison to the J bullets then I go hunting with it.

That test above was for .30 cal bullets of about 170 gr. If I was testing 150 gr cast then I would use a 150 gr J bullet from a cartridge with comparable velocity. Or if I was testing another caliber I would use a J bullet common to that caliber at the cast bullet velocity of 2000-2200 fps.

Over the years I've pretty much figured which alloys will expand out to 200 yards at 2000-2200 fps muzzle velocity yet hold together well at 25 yards and give good penetration. With 311041 it doesn't much matter what cartridge it is loaded in if the muzzle velocity is 2000-2200 fps then the bullet will perform. When I'm using a new bullet such as the 35-200-FN in the .35 Remington I will cast the bullets of a known maleable alloy and test expansin at 25 and 200 yards. I will test the cast bullets (FN and 3 different depth HPs) against the factory Remington 200 gr J bullet load.

Anyway, that's how I figure it out. Harcast bullets with a decent meplat will kill big game ok but like I said; I prefer a bullet that expands when using a rifle.

Larry Gibson

[John F.]

"Over the years I've pretty much figured which alloys will expand out to 200 yards at 2000-2200 fps muzzle velocity yet hold together well at 25 yards and give good penetration. "

Good post! I'm curious to ask which alloys you like? Any special heat-treating, etc. required?

Thanks,
John

[Larry Gibson]

"Over the years I've pretty much figured which alloys will expand out to 200 yards at 2000-2200 fps muzzle velocity yet hold together well at 25 yards and give good penetration. "

Good post! I'm curious to ask which alloys you like? Any special heat-treating, etc. required?

Thanks,
John

Pretty Simple really; 1. new WWs + lead (50/50) + 2-3% Tin AC'd. 2."Magnum" shot with 3% or so antimony WQ'd from the mold. 3. New WWs + linotype 2/1 mix alloy AC'd.

The 1& 3 alloys work best with bullets having a sufficient meplat or HP'd to a correct depth. I like the 1/8" forster HPer as it is easy to adjust the depth of the HP and works well on .30-.375 diameter bullets. #1 alloy is my standard go to alloy these days as it almost always works well. I use #3 alloy in those bullets which will be driven to the 2300-2500 fps range. These may or many not be HP'd depending on the bullet and the game. An example here is the Lyman GC .375 bullet at 2400 fps out of my M70 375 H&H.

#2 alloy (magnum shot/lead antimony alloy only) WQ'd from the mould makes for a hard enough bulet to drive fast yet is maleable instead of brittle at the higher close range impact velocities. This is a good alloy for velocities in the 1900-2100 fps range with larger bullets of .375 - .458 using heavy for caliber bullets. A good alloy for medium weight bullets in other calibers.

Again, remember that I always test for expansion with a new casting of bullets in any alloy. If the test is successfull I cast a pretty good quanity of that bullet out of that alloy for future use.

For rifle velocities of 1300 - 1800 fps an alloy of 1-16 tin lead expands very nice for hunting purposes.

Larry Gibson

[John F.]

GREAT! Thanks very much for the good info!
John

[Marlin Junky]

Larry,

Very interesting post... thank you.

What is the BHN of your #3 alloy? Would this alloy be equivalent to oven treated wheel weights and if not, why?... because oven treated wheel weights can't be depended on to maintain their BHN value over time?

Thanks again,
MJ

[Larry Gibson]

Marlin Junky

Sorry for the delay in responding, didn't dee the post as yesterday I was flying from home (Washington) to North Carolina (Camp Lejuene) and most of my posts were made from airports waiting for the next flight.

Been a lot of years since I oven heat treated WWs and that was with old ones. I don't have the bh here and it's now irrelevant anyway. The newer ones are softer so I really on't know how they compare to OT'd WWs. I've not got the bh of the # alloy here so my answer will have to wait until I get home on the 20th. Quite frankly I don't think they are any where as hard but I'll have to wait until I get home to know for sure. I prefer #3 for a harder bullet as it does not shatter like WQ.d WWs is prone to do. It is maleable but holds together with minimal exansion or some if HP'd.

Larry Gibson

[Marlin Junky]

Thanks Larry,

The reason I asked is because I've been fooling around with oven heat-treated wheel weight metal of current manufacture (or relatively current, I guess) and am getting pretty good accuracy in a sloppy chambered Whelen by HT'ing at 425F for a bit over an hour. The BHN a couple days after HT'ing looks to be about 19. Maybe HP'd, these boolits will expand w/o fragmenting... testing is needed.

MJ

[Larry Gibson]

Marlin Junky

Keep in mind there is a difference between fragmenting and shattering, to me anyways. A hard, brittle bullet that just breaks up into small pieces when it hits an animal is useful only for smaller varmints. However a bullet that expands in a controlled manner and which may slough off the expanded petals while traveling through the game animal is a good thing. Most controlled cup and core jacketed bullets do the same. This is the desired effect I look for in a hunting cast bullet. Some like a large flat Meplat on a hard cast bullet which just smashes it's way through. I've found that works on the larger calibers. However on the medium and smaller calibers is not as effective as a bullet that expands well within the animal. Of course the external ballistics favor the smaller meplat bullets with higher BCs. Depending on hunting conditions and ranges of shots that may or may not be a usefull advantage.

None the less on a bullet such as the 311041 at 2000 fps out of a typical Marlin or Winchester Carbine the HP'd bullet of maleable alloy that expands well will kill deer or other big game quicker than just the plain FP given equal shots to the heart/lung. Granted, both will kill but the one kills quicker. That is why it is my choice. No criticism of those who use the FP but maybe I'm just getting soft in my old age. Lord knows I've killed a lot of critters, I just like to do it as quickly as I can these days when I do.

Some may ask why I just don't hunt with higher velocity jacketed bullets(?), well I do hunt with those to. However at the ranges I hunt with cast bullets I've found a well expanding one of good maleable alloy kills as well (as quick) as a good expanding jacketed bullet given the same cartridge. I've seen numerous deer shot with mondo magnums and even standard cartridges that are loaded with the current crop of "premium bullets" intended for much larger, tougher big game take a long time to die. The bullets whizzed straight through the deer with little damage. Anymore it troubles me greatly to see an animal suffer when I know I could have used a better bullet to kill it quicker. It pains me to watch animals suffer when others do that also. Conversely I've killed numerous deer with the same shots using an expanding cast bullet and the deer died very quickly. FPE, velocity and "premium" have to be taken in context when choosing the right bullet for the game. Most gun writers and thus most hunters seem to forget that. Ok, I'm off the pulpit, sorry.

Larry Gibson