Subsonic .223 in my AR-15

[freebullet]

Yep 22lr would be easier than what I'm doing but like you, I hope to use the 223 range Brass we get a bunch of and, make our own bullets instead of searching for overpriced unicorn ammo while retaining the ability to shoot full house 223 loads if needed.
Your not helping prevent me from getting/wanting a suppressor. Between you and l1a1 rocker I'm surprised I haven't filed the paper already. I figure the longer I put off the first one the less slippery the slope is?

 

[Ian]

Just got through coating and sizing 100 of Josh's 75 grainers, so I have them ready to go for in the morning. I'll continue testing/verifying loads. Plan to stick with Titegroup for the short term, but interaction with the powder is a bit of a concern in the long-term due to so much of the bullet sticking down below the neck. A dip in BLL might protect it, been thinking for a while of using something like Future acrylic floor wax for a base dip, but need more data on interactions. I'd also like to try small pistol primers, but standard ones run a danger of slam-fires even manually cycling the bolt, so if I do that it will be just a few which will be individually loaded.

Originally I was only looking to duplicate .22 LR group size (for most of my guns with bulk ammo that means about 3 MOA on a good day), but might as well start doing some actual tuning work and see if I can't get this reliably down to 1 MOA out to 100 yards. If I could tune out those outlying shots and keep to the 1 MOA or less core grouping that I've been seeing, that would be wonderful. Might be more trouble than it's worth, too. Time will tell.

 

[Ian]

More shooting today. Short version:

ACE 75 grainer, ACWW, powder coated, sized .2245", 2.7 grains Titegroup, no gas check, ten into 1" @50 yards, essentially duplicating previous tests.

Same, but with Hornady gas checks applied and sized .2245" before and again after coating, nine into 7/8" (first one flew way out after brushing/patching barrel).

MP NATO bullet, ACWW, powder coated, no gas check, sized .2245", 2.5 grains Titegroup, ten into 1.5" @ 50 yards. I think that one needs some more investigating.

This is hard to do with a 3 MOA red dot, I just more or less cover the fuzzy black patch up with the dot on whichever quadrant of the target I'm shooting. Not sure it would be possible for me to reliably aim better than 1", I may need to put a scope on this thing to really tell what's up, and I really like this carbine set up the way it is for now.

 

[Josh]

Have you tried the AL checks I sent? I may have missed it if so forgive me.

 

[freebullet]

Nice work Ian!

Which mp bullet 65 or 75? I have the 75 and am planning to use it when the pistol is ready.

 

[Ian]

55 MP bullet, the one 45 2.1 designed. L1A1 Rocker was kind enough to lend me his mould for testing.

Josh, I didn't try your .22 checks just yet, I was trying to get the mostest done with the leastest shooting and gas checks was a variable I didn't want to take on immediately. I already know how the Hornady checks do on your bullet, so I went with that.

 

[shootnlead]

I have got to start casting some .22's...all there is to it.

 

[Ian]

Just cast another five pounds of MP .22 NATOs myself, just to empty the pot of that particular alloy. Back to straight WW and Lee 45 TCs. Last weekend some friends and I blew through 100 of the 75 grain ACE bullets in my suppressed AR, I was impressed that the PC'd versions I've been using were grouping about 2" on paper at 100 yards, often less. We were shooting golf balls using the 3 MOA red dot and hitting more often than missing, just had to give it a 12-O'clock hold which worked out because the dot was a LOT bigger than the balls.

 

[fiver]

you know nu-finish is a polymer.
ah jeez I just remembered something I had set aside.

 

[RBHarter]

I see there is a discussion at NOE about a 100 gr 225......

 

[wquiles]

Man, nice thread. So if I read this right, the idea is:
- to have a 223 AR15 "as is", so it will shoot GI/military/hunting ammo reliably
- but develop a subsonic load that will stabilize and shot accurately
- preferably a fast twist (1-7 or 1-8), to stabilize "heavy" cast bullets
- but without any modification to the buffer/bolt/gas port/etc.
- so that it will NOT cycle at all (in fact, stay 'locked' in battery) after every shot
- so that you would have to manually pull back and release the bolt to cycle a new round?

Right?

 

[Ian]

You got it, Will. Counting some estate sale primers and garage sale stuff I was loading these for about $1.50/100 when .22 rimfire was $60-80/1000 if it could even be found.

 

[wquiles]

Very, very cool concept. I love it!

My daughter has been shooting her suppressed 10/22, but she is a little frustrated with the 100yard accuracy, wind effects, etc. so I am thinking a 223 rifle with low-velocity rounds would be the ticket.

I bought one of those really heavy Sagave 12fv rifles at Cabelas on special (close to $300 I think) for a future "project" gun, and I bought it on 223. But the varmint barrel is stupid heavy - I would have to cut it, thread it, and I bet the profile would still be too darn heavy, so I would likely have to flute it and/or profile it further. Even then, the rifle comes with an 1-9 twist, which might be a little "iffy" for the heavies:
Cabelas 12FV

But I have an un-used AR15 in 223 with a faster 1-8 16" barrel. The barrel is not threaded and it is fluted to very close to the end, so to thread it I will have to machine right to the fluting - it will not look good, I think. But it would provide for a viable option. Another option would be to simply swap that heavy, SS, fluted barrel for a thin, lightweight 16-20" barrel which I can then cut/thread for my 30 cal suppressors, thus leaving her rifle "intact" for her to enjoy at 50yards or less. Looking at Palmetto I can buy a 1-7 barrel for $80:
16" 1-7 threaded barrel

Need to think about it some more, and perhaps share with her the platform to see if she is interested in the AR15 before I do much more (been married to a wonderful woman for almost 30 years, so I learned NOT to assume anything when it comes to girls/women ).

 

[Ian]

Lots of options. The heavy Savage barrel might be good for the Lee bullet and shoot as is without the suppressor. With Titegroup, the lighter bullets make a report on par with standard velocity .22 rimfire from an equal length barrel. Still need to protect young ears, but a few shots here and there in the tomato patch or river bank won't hurt.

 

[fiver]

you could also go full wildcat and neck down 300 BO to 22 caliber for that bolt gun and screw a 1-7 twist blank on it.
I bet you could run some real heavy 90-100gr. bullets, with like 2-3grs of powder and run circles around both the quiet game and the 22lr.

 

[Brad]

Isn’t the 300 BO necked down to 22 the 221 Fireball?

 

[fiver]

not that I'm aware of, so,,,,,?? but it'd be close-nuff to modify data from maybe.

 

[Brad]

A little Google fu tells me a 300 BO is same as the 300-221 Firelball

The 221 case would have plenty of capacity for good shooting with cast.

 

[Spindrift]

My understanding is, the 300BLK, 300/221 Fireball and 300 Whisper have the same cartridge dimensions and use the same reloading tools. But there are subtle differences in the throat angle/length (mainly to circumvent proprietary issues connected to the Whisper cartridge, I think).

I have shot the .223 rem a little with cast, but have never really focused on it. The resurfacing of this thread gave me the inspiration I needed. Fired up the pot yesterday, and cast a bunch of MP 227-65 with my new brass 6-cav. Took a while to get it to casting temp, even with my pre-heating routine. But man, does it rain some bullets when it is in «the zone». Weighed the first 20 keepers, they were 62,9 +/- 0,2grs as cast. Which is good, for me.

I have a 1-12 ROT barrel, which may not stabilize this bullet at subsonic speeds- we’ll see. The bullet is still shorter than a Hornady 55grs flat base, softpoint- so it is worth a try.

 

[358156 hp]

I believe JD Jones signed off the rights of the 300 Whisper to allow the 300 AAC Blackout to proceed to commercial status. Knowing Kevin Brittingham, the original design has most likely been tweaked anyway. I see that JD recently sold SSK off, but continues to come in part time. SSK will now be part of the group that owns Lehigh Defense. This could be really cool!