AR 15 question

[colt 357]

OK I'll ask here because I was told by so many people that I couldn't shoot lead through my automatic handguns (.40 & 9mm) that they would lead and jam up and cause a host of other problems. I know this not to be true now as that is what I shoot through my .40 and 9. Thanks to this forum.
Now can you cast and shoot lead through a AR 15. One of the guys that said I couldn't cast for my handgun said you couldn't shoot lead through his AR 15.
So is it possible to shoot lead and what would be the tricks to do it.
What can't you shoot lead through. Didn't times of war and shortages of copper force some places to use mainly lead?

[lwknight]

I don't know much about AR15s but I'm pretty sure they did not exist during the copper shortages of WWII..

[colt 357]

the ar 15 was designed by eugene stoner late 50's early 60 i think

[scb]

I've been shooting a lot of lead thru my 300 Whisper in the last few months. Somewhere around 600 rounds or so. The only difference I've seen between lead and jacketed are some minor lead deposits on the "tail" of the bolt which is easily scraped off. Some worry about plugging the gas tube. My advice would be buy 2 or 3 extras and IF one gets plugged which I can't foresee, take it out and throw it away. Or what I might do is install an Adams Arms rod op. conversion. They can be completely disassembled and cleaned.

[357 Voodoo]

They shoot cast just fine. Slower powders work the best. Too fast of powder will not cycle the action.

[stubshaft]

Yes, you can. With a faster twist you may have to slow the boolit way down though. I have a HBar in 1 in 7 that won't group with anything going over 1400fps. Even the 225462 at 62grs.

[Larry Gibson]

Yes, you can. With a faster twist you may have to slow the boolit way down though. I have a HBar in 1 in 7 that won't group with anything going over 1400fps. Even the 225462 at 62grs.

Any idea just what the RPM happens to be with 1400 fps from a 7" twist? Hate to say it but there it is again, the RPM threshold at work.

Larry Gibson

[C.F.Plinker]

Any idea just what the RPM happens to be with 1400 fps from a 7" twist? Hate to say it but there it is again, the RPM threshold at work.

Larry Gibson

144,000 rpm

[Larry Gibson]

144,000 rpm

There you go, with that load/componants the bullet is over it's RPM threshold during flight. Some improvement can be made with slower burning powders and/or using some kind of filler (original buffer seems to be the choice). I just use super slow powders that give consistent ignition as putting a buffer filler in that small neck/case is more of a pain than I like to do, especially if quanity ammo is wanted for an AR.

I'm getting M193 accuracy with a 225462 at 2350 fps out of my 12" twist AR using RL22. Can't do that with my 7" twist AR or even my 9" twist ARs. Is it heat? Is it lube" Is it barrel harmonics? Funny how all my AR fast twist barrels and my bolt action fast twist .223 barrels along with my fast twist .308W barrels all just seem to have bad barrel harmonics with cast bullets at high velocity as some would have us believe. Or is it simply the centrifugal force of the higher RPM in the faster twist barrels that causes loss of accuracy given an equal velocity? But that's talking about the RPM threshold, understanding it and then dealing with it and that's another story.......

Larry Gibson

[Moonie]

I shoot cast in my AR-15. I use 18gr of H4895 with the 55gr Bator boolit and it cycles my midlength gas upper perfectly, with carbine spring and buffer. No leading whatsoever using WDWW.

[chris in va]

I shoot cast in my AR-15. I use 18gr of H4895 with the 55gr Bator boolit and it cycles my midlength gas upper perfectly, with carbine spring and buffer. No leading whatsoever using WDWW.

Now when you say 'leading', have you checked the gas tube and port? I tried to shoot cast with gas check through my AK and a ring of lead formed around the port, locking up the action after ~50 rounds.

[scb]

This is the leading that accumulated firing 50, 311365s thru my 300 Whisper. No where near enough to cause a stoppage. There was also a like amount inside the bolt carrier, very difficult for me to photograph. Both deposits were easily removed.

http://i487.photobucket.com/albums/rr236/scb2008/001-1.jpg

[Moonie]

Yes I have checked, I don't even have the buildup on my bolt or bolt carrier that scb does.

[andremajic]

I have also done limited firing with cast out of my ar-15 chambered in 300 blackout. So far so good, with no leading or deposits.
Accuracy is about 3-4 moa at 100m with cast.

The best accuracy I've got so far has been with 145 grain .308 prvi partizan bulk bullets, with 16.5 gr. h110, federal sr primers, resized 5.56 nato brass, and seated to max depth for reliable feeding. 1moa when I do my part.

Andy.

[troy_mclure]

there are like 4 group buys going on just for boolits for ar15 style rifles.

[scb]

OK here's what my 300 Whisper looks like having fired 500 rounds of various cast boolit loads with NO cleaning what so ever. It was still working fine but I've never fired 500 rounds thru any firearm without cleaning it.

http://i487.photobucket.com/albums/rr236/scb2008/006-1.jpg