Cast bullet shape for low velocity penetration?

[Naphtali]

Shooting black powder only, the projectile having a muzzle velocity of 700 fps, what cast bullet shape achieves the highest penetration?

I am assuming that whatever bullet shape has the most penetration, that shape will continue to hold its lead position regardless of bullet's mixture so long as any bullet tested has the same mixture, the same weight, and the same bore I.D. If this is incorrect, please let me know why.

I also assume that this bullet shape will hold its position regardless into what medium it is shot. If this is incorrect, please let me know why.

[wmitty]

Since sectional density is required to provide penetration, a cylindrical shape would be my guess. This neglects the very poor (in relation to a spire point ) exterior ballistics obtained by shooting a cylinder shaped boolit. Not sure about terminal ballistics; as to whether the cylinder would tumble in flesh. I assume it would tend to do so; otherwise the makers of solid j.b.'s would not go to the trouble of constructing an roundnose or truncated cone for these type projectiles. Or maybe the ogive on these solids is simply to improve feeding from a magazine and the cylinder would be the best shape, disregarding aerodynamic considerations.

[Digital Dan]

1st paragraph question? Look at a .22 RF bullet for a favorable nose form.

Para 2&3: I do not understand your questions.

[btroj]

Look at the work done on large bore solids in the 80s and 90s. The went to a round nose with a flat on the end. Sort of a really long RNFP type bullet.

This was found to penetrate straighter than a traditional round nose.

If I understand the last couple questions then no, this won't always be the best independant of alloy. If the alloy is soft enough to deform some then the shape the bullet takes on determines what happens from then on. If you really go with 700 fps then deformation isn't likely to occur at all.

Bullet weight is gonna make a difference too. Sectional density always matters in penetrating.

[Yodogsandman]

A round nose or pointed profile would be better for penetrating heavy winter clothing or thick hide at lower velocities.

[44man]

I only use traditional with round balls but shoot faster then 700. After hundreds of deer, I have never recovered a single ball. I also killed many deer with the Ruger old Army and round balls and never recovered a ball.
The new inlines can alter things but I believe I would use a pure lead boolit with a flat on the nose.
I had a TC that shot the Maxi Ball and it also worked wonderful.
At 700 fps, you will lack energy and penetration.

[MBTcustom]

If the focus is penetration only, the standard round ball cast of WQ COWW will punch a hole in just about anything.

Another design you might considered is the pointed pistol bullet design, called the Lyman Penetrator 429303.
NOE makes a simar copy as seen here:
http://noebulletmolds.com/NV/product_info.php?cPath=37&products_id=66
Again, cast it hard and get ready to pencil through just about anything.

I actually had some 357 Magnum "metal piercing" ammo at one time that had a jacketed bullet shaped just like this. It was loaded with a hollow base bullet with a jacket that was formed to a point on the nose. I pulled one down once and melted the lead out of it to find that the jacket was actually quite thin.

If you want penetration, expansion is your enemy, so cast your bullets out of an antimonial lead of some sort with very little tin and heat treat them.
basically, everything you're not supposed to do for a good hunting bullet.
Instead of soft, flat, and slow, you want to go hard as diamonds, pointy, and fast as you can shoot it.

[Outpost75]

Flat-based, round-nosed bullets similar to the 40-grain .22LR and 158-grain LRN in. 38 Special typically flip 180 degrees in soft targets and continue base first. They are easily deflected when striking bone and cannot be depended upon to continue on a straight path to break an off side shoulder on big game.

Better penetration and improved, reliable crush characteristics are achieved by using an ogival flat-nosed bullet with meplat not less than 1/2 of bullet diameter, with the ideal being about 0.7 of meplat diameter. Larger meplats can be used successfully at short range, but their dispersion will be nonlinear at longer ranges over 100 yards. Traditional type black powder .44-40 loads with properly designed and well fitting soft bullets of 6-8 BHN, launched at 1300 fps from a rifle, retain their accuracy to 300 yards or more, penetrate 24+ inches of gelatin at 50 yards and reliably expand to .60 caliber.

The exact same load, when fired from a revolver at about 1000 fps will penetrate 30+ inches of gelatin and continue on a straight path through the game without yaw or tumbling. I have used such loads in the .44-40, .45 Colt and .44 Magnum for over 40 years and found them very effective on deer, hogs and black bear. At the same time they kill edible game such as turkey without blowing them to flinders, and you can eat right up to the bullet hole!

Bullets of proper contour which I recommend are the Accurate 43-215C, 43-230G and others which are similar. Hard alloy is neither necessary nor desired. I use 1:40 tin/lead from Roto Metals for my hunting loads in .44-40, .45 Colt and .44 Magnum. I do not use gaschecks, but limit velocity of smokeless rifle loads to about 1450 fps. My rifle loads, when fired in a strong revolver, such as the Ruger, do almost 1100 fps.

Higher velocity and harder alloys are unnecessary. Nor do I feel that bullets heavier than 230 grains are required in the .44 Magnum or .45 for non-dangerous game. I won't kid myself in grizzly country and would carry a 12-ga. shotgun loaded with 3" Magnum 00 buckshot. No handgun is adequate in a hot breath confrontation with a big bear.

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[MtGun44]

Pointed yaws no good for deep penetration, flat point on a slightly rounded
nose seems to drive the straightest about the same as SWCs like Keith designs.

Pure round noses seem to yaw, but this depends a LOT on twist
rate. The old 160 RN 6.5 mm and 175 RN 7mm bullets with
extremely fast twist ( 7mm original military twist was one turn
in 8.66 inches) would drive through forever unless they hit a hard bone.