Subsonic .223 in my AR-15

Ian

Notorious member
Well, that's mighty generous and I certainly appreciate the offer, but the direction I want to go next is the other way, like 75 grains or so. Turns out I ruined that two-cavity that I PB'd, apparently I belled the bases and they lock in the mould badly. That's what I get for being too cheap to grind one of my good bits down to .225" and instead tried to sand the cavities up to that from the smaller drill size.

I suppose I should check out NOE's heavier .22s. If I go ahead and press out the alignment pins before using the mould and grind/polish a proper taper on them, then the moulds work like they should and I'm a little more inclined to start buying them again.
 

Ian

Notorious member
Enjoyed shooting it yesterday. VERY quiet! There's a real "giggle factor" when you get into the "stupid quiet" territory.

Like that, did you? Shredded some two-by yellow pine blocks handily, too. I cast about three pounds of those NATO bullets last night, your little mould runs like a champ. Not sure if they'll work well without gas checks, but I aim to find out.
 

Ian

Notorious member
Ok, I might need to cast more of those little pills. Just ran a few through the Lee sizer, put on a coat of straight BLL, let them dry five minutes while I prepped ten cases and loaded them up with 2.4 grains of TG. Shot them at 20 yards across my driveway a few minutes ago and made a ragged hole. I might have to put a scope on this thing for accuracy testing, the groups are smaller than the red dot and my eyes are getting to where pinpoint accuracy with a red dot is very difficult even with some targets I printed just for the purpose.

No gas checks! Patched the bore and got some black out, but zero lead and nothing I can see from either end of the barrel. In order to get both bands inside the neck I had to seat these a lot deeper than I would have preferred. Still, that didn't cause any throat leading. I need to load more of these and try at longer range.
 

Ian

Notorious member
Will do, data is easy to generate when I can shoot at all hours by flashlight just stepping outside.

JWFilips mentioned Winchester small pistol primers earlier in the thread, I'm going to see what I have in that department and give it a go soon, maybe the next tests. One coat of BLL is doing the trick nicely here, so that's all sorted.
 

Ian

Notorious member
All right, JOSH, we need to figure out an equitable price on this mould because you aren't getting it back. :) Whatever you were getting for them originally plus freight, how's that?

I cast up a pile of the ACE heavy .22s this morning and went straight to working up a load. Settled on 2.7 grains of TG and a CCI small PISTOL primer. Seated the bullets so that if they were any longer they would bind in the magazine. I was getting around 1" groups at 25 yards and 3-4" groups at 50 yards without gas checks, then I tried WITH checks and three things happened: The load got a lot more quiet, the FPS dropped off by about 60 fps down to low 900s, and 50-yard groups of ten started coming in under an inch. I had recovered a few shot without checks and found that gas was washing up the base band about halfway, on each side of each groove cut by the lands. I think the checks pushed the burn curve way back into the case and used up the powder sooner, both dropping velocity some and knocking quite a few dBs off the suppressed report, meaning it's back to movie-quiet now with these heavier bullets.

OK, so 918 fps average groups for gas-checked bullets turning in 1.75 MOA at 50 yards isn't impressive. I get it. BUT, this is a 5.56 NATO chamber and tumble-lube, mixed GI brass, and bullets still warm from being cast. And they were fed from the magazine by racking the charging handle, which if you don't know is murder on bullet noses. Also, the rounds can't engrave the throat or fit tightly due to the weak camming force of the AR system, so I don't have the crutch of engraving the nose to lean on. I'm very pleased.

I'm also going to have to come up with a better back stop for shooting out of the front door, these heavy .22s plow right through the 15" cedar stump I have set up across my driveway. In fact, some of the initial testing this morning split it in two.

Also, at 50 yards, after passing through a self-healing polymer "gong" swinger target to which I pin my paper targets, the bullets turn completely sideways within 8" and do murder to a plastic bucket full of sand.

My only complaint is the lube, still don't have it dialed in to eliminate the first shot flyer, which is actually bad enough to be a show-stopper, like 3" high at 25 yards after a 20 minute cooldown.

I may try some real lube on these and see what gives.
 

Josh

Well-Known Member
Glad you like it, that was also the only mould I ran with a stainless steel sprue plate. No rust, ever... :) do me a favor and run that booger up to the 2700 fps area with some varget or 4064, I have had very favorable results doing so. Also for cheap subsonic plinking I can send you some AL 22 checks, just seat them before you size.

I will check the price on that mould, (wish I could have found you a 6 cavity, but the last one was in use by me) IIRC it was $100. I need to buy off Dan for a 1903 barrel so this comes in at a great time.
 

Ian

Notorious member
Sounds good to me, PM your addy and total with freight and I'll get a check headed your way. For best quality bullets, a four-cavity is perfect, actually. I wondered about the sprue plate, it didn't seem to be magnetic but I though if it were aluminum it had to be the hardest stuff ever made. I like it because it doesn't wear where it engages the stop screw, and also lead doesn't want to stick to it.

So let's see.....2700 fps, out of a seven twist, comes to 277,714 RPM. Think that's fast enough to stabilize? :p
 

Josh

Well-Known Member
Yeah, I think that will stabilize, do you need a lesson in RPM Fact... eerrrrr... Theory
 

fiver

Well-Known Member
I clicked on the thread and all I seen was Josh's post about the rpm thing and I just about launched my mouse across the room.
good thing I scrolled up real quick.
 

Josh

Well-Known Member
I clicked on the thread and all I seen was Josh's post about the rpm thing and I just about launched my mouse across the room.
good thing I scrolled up real quick.
No chuckle at all? You don't wanna know how a monolithic solid can be torn up by spinning? I got a few Scientologist people who can help, I also hear they fixed the undersize Lyman mould issue...
 

Ian

Notorious member
Well, well. More testing today.

I got some new containers (actually bought some this time) for doing my Airsoft bb/shake powder coating and got the graphite black poly tgic coating going well for my Lee 300 BLK bullets, and it hit me that I really need to try powder coating some .22s. So I did a hand full (50 or so) Lee 55 grainers and about the same amount of ACE 75 grain bullets, both sans gas checks. They came out really nice and the long-nosed ACE bullet chambered just fine when seated a tad deeper than I do with BLL.

Went to the range and set up at 50 yards and dialed up my Bushnell red dot (3 moa) at 25 yards to get on paper, the bore-sight was close enough and I did some correcting at 50, then shot a ten-shot group totaling 1-1/8".

Encouraged by that, I went back and loaded up five each of the coated 55s at the same 2.4 grains TG, then upped the charge to 2.6 grains and loaded five more ACE 75s (powder coated, no gas check) and five identical loads with gas check and one coat of BLL.

This time the ACE bullets put four into 7/16" with one outlier making 7/8" (probably typical dispersion, ten would probably open up to around an inch).

The five Lee bullets scattered out a little over 2", pretty unimpressive. I'm sure there's more I could do there....but I'm not stuck with just that mould.

The gas checked/BLL group of five immediately opened up to a scattered 1-1/8" with two touching. I shot those last without cleaning the barrel, no telling what it would have done had I shot more and let the barrel fouling normalize to BLL, maybe it would get worse, maybe better. There IS not fouling with the PC bullets, nor any first-shot flyers.

All in all I think I'm going to stick with the powder-coated ACE bullets, this carbine really likes them and my Colt HBAR rifle also has a 1-in-7" twist so they should work pretty well in it too. With no other .223s to worry about, I'm going to spend more time on this heavy bullet for now. Sorry about the picture being sideways, I uploaded it directly and that's the way my camera saved it on portrait setting. 100_4405.JPG
 
F

freebullet

Guest
Very nice!

Great thread & testing Ian.

I have an ar pistol I'm considering trying to do similar with but hopefully, make it functional. Have a bit more fitting/assembly yet.
 

Ian

Notorious member
The web is light on data for this, especially with PC. Since there seems to be some interest, I'll keep posting my results. I'm having a ball working with this AR suppressed, I can snap my fingers louder than the shots!

I was going to build an AR pistol with a 7.5" barrel and blank off the gas port for use with a .22 LR conversion, but the conversion I have is an old Colt and extra magazines are hard to find. A more modern conversion setup for a .223 barrel, or even a dedicated .22 LR barrel would be neat if the barrel was chopped to about four inches and threaded for a suppressor. A four inch barrel should make even high-velocity .22s subsonic, thus cheaper for the system to shoot. Also, some of the conversions don't utilize the buffer assembly at all, so you could just put a plug in the back and call it done. I wouldn't even put a handguard on it. That would be the easiest way I can think of to get a semi-auto .22 caliber AR pistol to reliably cycle and be subsonic.