Need help with my AR15 & Mihec Cast bullet

[badluther]

a3fd2

[Doc_Stihl]

Are you weight sorting the bullets?

The first thing I'd try would be to swap out the pure in that alloy for WW's and water drop them. I'd want some really hard bullets in a 1:7".

Is the bullet being deformed as it's chambered? If you make up a couple dummy's and feed them from the mag a few times are they bumped and scratched?

[badluther]

a3fd2

[Larry Gibson]

I'd change the alloy to 80/20 lino/lead and AC them for 7-10 days before doing anything with them. Then I would get a few Hornady GCs (some one might spare you some, if not PM me). Try them on the new alloyed bullets with the same load. If that solves the flyer problem then you're good to go with probably thicker GC material. If not then the flyer problem is from pushing the bullets too fast for the very short 7" twist barrel. A slower powder may be needed. However, are you using a dacron filler? If not drop back to 14 gr TAC and use a 1/2 gr dacron filler. You'll want to work up to just have reliable functioning and no more. The best accuracy will more than likely be at that point.

Larry Gibson

[Doc_Stihl]

Are you trimming your brass?
How are you crimping?

[HDS]

Yeah get one of those plastic sorting boxes to keep them separate, my mold dropped in the 62gr range and I found it varied from 61.9 to 63 grains. I sort the bullet to .1 grains difference.

[badluther]

a3fd2

[popper]

Don't worry about the scratch. My 308 carbine (1:10) does the same thing and does 1.5" @ 50 with 4895, close to TAC. You are running ~ 2400 fps in a 1:7, so I agree with Larry, alloy problem. Add some shot and HT or add Cu and reduce the Sb. Or slow down and use doggy stuffing if it will cycle properly.

[DLCTEX]

I'd use 1/2 gr.(.5) Dacron and don't pack it in, leave it fluffy.