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Lloyd Smale
06-30-2019, 07:25 AM
im building a 18 inch ar10 and was wondering if anyone has fooled with pc coated cast in the 308 at full power or near full power and if you got it to shoot expectably (lets say 2moa) I can do that or a little better with full power in the black out but this is an entirely new level of power for cast bullets for me.

ole_270
06-30-2019, 10:06 PM
Not an ar but I've been playing with an old JC Higgins M51-L in 308. Bore and throat are fairly large. I've pretty much settled on the Saeco #315 clone by NOE, sized to .3115, to be able to partially fill and bridge the throat. I'm using PC, dropping from the 400-425 deg oven into cold water to quench. Alloy runs 1.4% Sn, 2.9% Sb with probably a bit of arsenic in there from the WW that were mixed in.
I worked up to 2450 fps with H4350 and H4831 just seeing how far I could go. Accuracy was still under 2" for 5 shots at 100 yards, but better accuracy was had at 2000-2250 fps. The lands are pretty narrow and a bit worn so that may of held it down some. 180 grain bullet at 2000-2250 will work for any deer I'll ever see and be a good practice round without full recoil.

Lloyd Smale
07-01-2019, 06:58 AM
thanks. That at least makes me think its possible.

Larry Gibson
07-01-2019, 09:26 AM
It might be plausible with PC'd cast of a hard alloy with some copper added. Popper seems to have mastered the technique with such in his ARs. Velocities in the 2300 to 2400 fps range with 2 moa accuracy have been reported at leat at 50 and 100 yards, maybe further(?). Given your AR probably has a 10" twist a 180 - 200 gr cast bullet at 1800 - 2000 fps should achieve that w/o much ado. Loaded over 4895 the action will also function reliably.

dogmower
07-09-2019, 06:47 PM
I've used the lyman 311413 sized to .311, pc, over 20-25 grains of imr 4895 in my hk91 clone. best accuracy was at 20 grains and this did cycle the action.

popper
07-15-2019, 11:16 PM
16" dpms carbine, 31-165c PC,GC, 2400fps. MOA @ 200. 24" barrel is 2700. Jacket loads of 335 or 4895. 4% sb with some cu, WD after cooking.

samari46
07-16-2019, 01:19 AM
Saeco 315 is one I haven't tried as yet. test dummies show heavy land engagement and also the Saeco version of the RG4 bullet. Have two rifles I'd like to try them in. My Sako 75 Hunter with detachable mag and an old post '64 model 70 match rifle. Or maybe my sportered 1903A3 with some wear on the bbl. The Sako has about 1100 rounds through the tube but looks like new. the M79 hasn't been fired since I bought it years ago and does look like not many rounds fired. The A3 does have many rounds fired so maybe that is the one to start with except iron sights. My old eyes don't do well with irons. Frank