RCBS 22-055 FN In AR Help

[rnhathaway]

I got a new(to me) mold yesterday and cast, sized and loaded some up today and shot them. I tried 8gr of Unique and they shot well but didn't cycle the bolt. Chronoed them at 1920ish FPS. Lyman manual shows a max charge of 9.0 grs. Should I try higher than that or should I try a different powder?
Thanks,
RNHathaway

[nighthunter]

I've had better results using 4895. Either IMR or H. Start around 18.5 and work up. I have gone considerably higher with accuracy and no leading.

Nighthunter

[fcvan]

Unique is too fast burning to cycle the action. It attains pressure quickly and drops off before the expanding gas can cycle the bolt. Although I don't shoot the RCBS boolit, I do shoot the Lyman 225-415 55 grain boolit. 14 grains of 4227 provides 2250 fps and cycles the action of my Mini 14 and my brothers AR platform rifle with approximately 25,000 CUP. The round is quiet compared to factory loads but a ton of fun to shoot. Factory FMJ loads pierce neat holes into tin cans. The cast boolit shreds tin cans. We are still tweaking with the load depth to maximize accuracy but obtained decent groups at 100 yards and were able to ring a 12" gong at 200 yards while shooting off hand. Good enough for us!

[runfiverun]

you need enough gas volume to make the bolt go backwards.

[nhrifle]

I just started experimenting with that boolit, cast from the NOE mould. I seat them to the middle of the front driving band with no crimp. Wasn't real happy with the results from AA5744, so I tried some IMR4064 I've had for awhile. I started at 15 grains, upped the charge to 17 grains where the action started to cycle. At 18 grains, I was beginning to see some respectable groups, but daylight was almost gone so I called it for a day. Will do more this weekend. It is looking like the midrange burning speed powders are going to be a winner with this one.

My rifle is a 20" DPMS AR with free floated barrel and M16 carrier.

[rnhathaway]

I have some Varget. Would that work or would it be too slow?

[bruce drake]

Varget will work. Like NHRifle did, start with around 15-16gr and build up. Its a good Medium burn rate propellant and should work fine.

[rnhathaway]

Thanks!

[nhrifle]

I love Varget, but I won't use it for this application since my supply is for my competition load (specific brass, bullet, powder, etc.). Please post results if you use it, I may have to revisit my thoughts on that.

[runfiverun]

around 18-20 grs you should find a happy node with the varget.
you might even find another one around 22-23 grs.
assuming a 9 twist.

[rnhathaway]

1-7" I know it's fast for a cast bullet, I'm experimenting more than anything.

[ipijohn]

I have been shooting a Lyman 228367 boolit sized to 225, because I had the mold. It is 60 gr with an aluminum gas check over 20 grains of IMR 4895. I have had good success for me (1.0 inch at 50 yards)

[runfiverun]

try the 18grs and go from there.
the 1-7 should do okay with that.

[JedYonkers]

I've had better results using 4895. Either IMR or H. Start around 18.5 and work up. I have gone considerably higher with accuracy and no leading.

Nighthunter

I tried fast powders as well and had no luck. I settled on 19 grains of IMR 4895, I suspect something along the lines of varget would work as well.

[grubbylabs]

What about H-335 or some thing similar? I would like to load on the progressive and be able to load a lot of plinking bullets.

[rnhathaway]

What about H-335 or some thing similar? I would like to load on the progressive and be able to load a lot of plinking bullets.

H-335 is only 2 powders slower than IMR 4895. If it works for that then it should work fine with H-335