Pellet Flight Stability Question

[airiscool]

Pellets aren't the only "wasp waisted" projectiles that suffer from instability.

About 12 years ago a friend and I did some reloading and testing of Lyman wasp wasited 12 and 20 ga saboted slugs in both rifled and smooth bore shotguns. Accuracy was miserable.

Also, some of the early rifled barrel shotgun sabots such as those from Winchester and Federal were long, wasp waisted slugs and had accuracy/stability problems. With many rifled shotguns, they would actually turn sideways and "key-hole" the target out beyond 50-60 yards. Those designs were dropped for more bullet like sabots such as the copper solids, which are much more stabile at long range.

Paul.

[VINNY]

WOW! That was pure poetry! I have a tear..Beautiful!

[onemountain]

um wow thanks for the praise folks. I wrote it right after a chemistry test; I guess maybe I was still in 'focused mode' lol.

[Mark 611]

That was very spot on Eric!

[popadave]

Really great post Eric!!!!

[RedFeather]

The short answer - The diabolo (diablo?) or shuttle-cock pellet does not do well over 1100 fps due to the transitional forces breaking and then falling under the speed of sound. Simple as that. PCP's shoot well at super sonic speeds because they are shooting more traditional-shaped bullets. A spitzer (pointed) boat tailed bullet will be very accurate over 1100fps.

As to the Sierra man, lead does not deform at 1200 fps. Why would it? You can shoot a lead bullet into test media and recover it, intact, with no apparent damage. If you shoot a soft lead bullet over a heavy charge without a gas check on the base, it might melt the bottom, but that's from the powder, not the air.

[48 Shooter]

RedFeather - 4/22/2010  3:38 PM

As to the Sierra man, lead does not deform at 1200 fps. Why would it?  You can shoot a lead bullet into test media and recover it, intact, with no apparent damage.  If you shoot a soft lead bullet over a heavy charge without a gas check on the base, it might melt the bottom, but that's from the powder, not the air.

I never thought about the why's of his answer. I assume that Sierra bullets has performed testing that led to this answer. Otherwise why would he tell me this? I'm by no means a Ballistics guru, so when I have questions I call or email bullet makers for my answers.

Daniel

[airiscool]

Dan,
Not to doubt you, or put you on the spot, but I also wondered about that Sierra man's statement of lead distorting at over 1200fps .

As you may know, there are quite a few 22 rimfire non-jacketed lead, high velocity rounds that seem to do well at over 1200fps.

I would be interested to know more if you get to talk to him again.

Paul.

[Truman]

He might be referring to the pellet skirt getting blown out which I suppose is a possibility on some thin walled pellets! Anyway, nice description Eric and Red for putting it in a nut shell!