Sig 516 5.56 16" 62gr 98/2 pc'ed at approx 2700fps

[Smoke4320]

Thought I would share my newest project
It's a Sig 516 5.56 16" 1-7 twist
MP 227-65fn mold
98/2 alloy
Gas checked, pc'ed flame red then sized .225
Bullets ended up weighing 62-63 grns
20.6 grs of H4895
50 yds 5 shots
Approx 2700 FPS
Std case prep on LC cases, did not weight sort cases or bullets
RCBS SB die set and Lyman M die
Attachment 178619

[tzzler44]

Awesome!

OAL?

[greenhornet-1]

Looking good!

[Smoke4320]

oal 2.185 IS CORRECT

[Moonie]

Well done Smoke

[Smoke4320]

I hope to soon set up the lab radar and fire another group for the 3rd conformation of group size
velocity is a guess right now.. basing on loads for jacketed bullets same weight and powder charge
in the past that has proved to be very close... generally less than 50 FPS either way

Still dealing with the BIL death and associated issues

[Gamsek]

Had the same mold, got 63grs GC and PC, this is in 223....

[Gamsek]

And this in 222 with 1/14",so after I reached 2000fps group stabilized. No special load development, just having fun.

[Lloyd Smale]

I'm going to have to get me a 22 mold. I never bothered because lube sized bullets just didn't fair well at velocitys that are needed to run an ar. But it looks like this might be the answer.

Thought I would share my newest project
It's a Sig 516 5.56 16" 1-7 twist
MP 227-65fn mold
98/2 alloy
Gas checked, pc'ed flame red then sized .225
Bullets ended up weighing 62-63 grns
20.6 grs of H4895
50 yds 5 shots
Approx 2700 FPS
Std case prep on LC cases, did not weight sort cases or bullets
RCBS SB die set and Lyman M die
Attachment 178619

[7Acres]

Very cool, Smoke! Glad to see this was a success for you. I am about to go down this road myself. I've got an MP 227-75 mold. I want to PC the boolits and shoot them through my Sig Sauer 5.56 1:7 16" barrel. Looks like I may have the exact same barrel you've got. Did you slug your barrel to settle on sizing to .225?

[Smoke4320]

yes sir mine was a dead on 223 barrel size
Just got my NOE 226 sizer so I will try that later . I usually go .003 over bore

[Alan Bycroft]

Well guys....im having miserable luck with mine! My AR is a 16" bbl, 1x9 twist basic Delton upper. I casted boolits with my RCBS 22-55-SP mold using straight linotype, pc with Smoke's and no gc. I use IMR4895...started at 18.5 and up to 21.0 grains, set OAL to 2.165. They are accurate enough at 25 yards, but only one shot at a time...not enough pressure to cycle the bolt completely, so each successive round is a jamb...rack it out, recharge the handle, shoot...jamb. I got a pretty stern admonishment by GunBlue490 on his YT channel for using reduced loads in an AR...says it's very dangerous. Looking at the load data, though, it really isn't a reduced load at the 21.0 level...just a starting load. Looks like I'm going to accept defeat and buy a bolt action .223.

[Smoke4320]

Hornady 9th edition shows 22.7 as starting load for IMR 4895 Approx 2800 FPS

[Alan Bycroft]

That sounds better. I only have a Lynam 49th edition and is has 21.0 starting for 55grn cast.

[kbstenberg]

Smoke I am assuming full cycle to next round.

[Smoke4320]

yes sir 100% function

Now this is a piston gun ...NOT DI (gas )

[Moonie]

I had full cycling with 16gr H4895 with 55gr boolits with a 16" carbine gas AR years ago with standard lubed boolits. Just starting on working up loads for a new 22 Nosler upper.

[Alan Bycroft]

Do either of you guys gc your boolits? Maybe that's what my problem is.

[Smoke4320]

Absolutely of me anything over 2000 FPS gets a gas check for accuracy.. on the 223 I install the check while sizing , then coat, then size again
doing it this way gives me great confidence that a check will not come off in my suppressor
done many tests with different calibers and alloys and so far this as worked well for me
I am shooting 50/50/2 COWW/PB/HSB. Yes the numbers don't add up.. I mix 50/50 then add 2 % Hi Speed Billet (for the small amount of copper and the tin)

[Moonie]

Do either of you guys gc your boolits? Maybe that's what my problem is.

If you aren't using gas checks for these things over 2000fps you are most likely going to get shotgun patterns. I've powder coated some NOE 221's but have to find my 22 caliber gas checks before I can continue with this test lol. I do have a little less than half of an 8 pounder of H4895 I bought for reduced gas gun cast loads.