223/5.56 subsonic

[Tackleberry41]

I know the question always asked is why? Like that stops anybody in this forum in their strange quests for stuff nobody else wants. I know 22lr does pretty much the same job, but I cant shoot 22lr thru my 5.56 bolt gun. And it will be going thru a can. You can also get more weight in a 223.

I messed with it before but always got such garbage results. Either really low velocity where I risked them stuck in the barrel or accuracy killing wide swings in velocity. I tried the usual recipes found on the web: trailboss, titegroup or bullseye. I had extreme spreads w trailboss of 220fps. Needless to say that was not going to work. W a 1-9 twist barrel, 60gr flatbase is about as heavy as I can go with a jacketed bullet. Boat tailed anything wont really work. They sell a hollow point 45gr for the 218 bee that looks like it would work pretty well, but they dont make them heavier.

Only mold I have is the lyman 55gr. It works in my bolt gun, not terribly accurate. I want them to fit in the magazine, which makes them a bit short for best accuracy w that bullet. But I can get them to work without the large swings in velocity. I used solo 1000 that I have been using in all my other subsonic ammo. And drilled the flashholes out, maybe not critical in larger calibers. But sure seems to be important in the 223. 2.5gr of S1000 got me 1019fps w the 55gr and ES of only 11fps. I used some 60gr SP jacketed I had, 3.5gr of S1000 got me avg 1017fps, w ES of 64.43 fps. Not exactly terrible. Pretty dang accurate.

What I am looking for is a heavier mold. That 60gr SP thats stable is .755 long. So any cast the same length should work. NOE has a 70gr RN, anybody ever use it?

http://noebulletmolds.com/NV/product_info.php?cPath=24_111&products_id=1478

Powder coated would imagine it can be driven full velocity if needed.

[Larry Gibson]

Odds are with subsonic jacketed bullets you will stick one in the barrel....been there done that.......

With cast bullets my best results were with 225438 cast soft and TL'd in LLA lightly. A GC was then crimped on the base w/o sizing the bullet. Accuracy w/o GC wasn't too bad in 12" twists but didn't fare well in 7-9" twist ARs. I didn't have to drill the flash holes. I loaded them over 2.2 gr Bullseye....no wad or filler. Velocity was 1060 fps and they were very quiet out of an AR with a can.....pretty quiet w/o the can too.

Of course they would not function the action.

Max length of bullet to be stable at 1000 fps in 9" twist is .8".

Larry Gibson

[vincewarde]

I know 22lr does pretty much the same job, but I cant shoot 22lr thru my 5.56 bolt gun.

Actually, you can. Chamber adapters are made for just this purpose.

http://www.mcace.com/adapters.htm

[Hick]

I shoot a 60 grain CB with 3.5 grains of W231 in my 223 Rem CZ-527 and get 1300 fps -- essentially the same as 22LR. Haven't tried it with my 55 gr FMJ yet but that's on my list. I did it precisely so that I could do some "22" plinking without going out and buying 22LR. Using a cast bullet its less money than 22LR. I realize that's not subsonic, but I think it would be possible.

[SUIScide]

With cast bullets my best results were with 225438 cast soft and TL'd in LLA lightly. A GC was then crimped on the base w/o sizing the bullet. Accuracy w/o GC wasn't too bad in 12" twists but didn't fare well in 7-9" twist ARs. I didn't have to drill the flash holes. I loaded them over 2.2 gr Bullseye....no wad or filler. Velocity was 1060 fps and they were very quiet out of an AR with a can.....pretty quiet w/o the can too.

Of course they would not function the action.

Max length of bullet to be stable at 1000 fps in 9" twist is .8".

Larry Gibson[/QUOTE]

I always worry about shooting GC's through a can. IDK if that's justified but if one came off it could really mess things up, especially on a follow up shot

[gpidaho]

My 223 Rem 700 loves this load. Noe 60gr Rn COL 2.190 over 3.5gr TiteGroup. I sold all but one of my 22rimfires. Cheaper to shoot these than 10 to 15 cent RF Ammo and more fun. Gp

[GhostHawk]

As I see it you are trying to take a semi auto with a "go fast" barrel designed to shoot factory loads up to or over 3000 fps and make it go slow.

That is never going to be ideal. Too many compromises.

But Larry has given you a path forward, run with it.

I don't run mine that slow, and I shoot mine in a 1-12 H&R Single shot. I use 4-5 grains of Red Dot under the Bator bullet, no gc, and was aiming for 1300 - 1350 fps. So I could not spend the 3 cents each on gas checks. Yes I am a tight bastige.

But if you want to go slow, you need to start with a tractor, lots of power, geared low.
Not a formula one racer, or indy car. Also lots of power, but designed for the fast side.

You can take a 1 in 12 barrel and load it slow with heavy bullets and get someplace interesting with some work.

[17nut]

One thing i have found with cast at slow speeds is that to much lube results in high SD.
They get to slippery. When i cut dow to lubing the bottom groove SD's drop like a stone.

[Shiloh]

With a 1-9 twist barrel, 60gr flatbase is about as heavy as I can go with a jacketed bullet. Boat tailed anything wont really work. They sell a hollow point 45gr for the 218 bee that looks like it would work pretty well, but they dont make them heavier.


Depends on the barrel. I have seen one mans 1-9 twist shoot Hornady 68 grain pretty well. and anything up to it. There are other 1-9 that won't.This is from watching the local HP guys on Sunday afternoons.

Mine stabilizes 63 gr. but nothing heavier. Anything past 200 yards and you will probably need a 1-8 twist. 1-7 seems to be the current favorite of manufactureres.

Shiloh

[Tackleberry41]

It depends on the bullet. I tried 62gr FMJ pulled bullets I had, not stable, the boat tail makes them to long to be stable. A spitzer 60 gr works fine, .750in seems to be the limit. Get up over 60gr not easy to find them in flat base. Im not doing it to be cheaper than a 22lr or replace it. I have plenty of subsonic 22 ammo, the local gun shop has plenty on the shelf. Just an exercise in 'will this work'? I have worked up some 22 hornet loads for the 5.56 bolt gun using blue dot. I have found the smaller the bullet the less noise it makes going supersonic. And using half the powder of a 223, you can use a smaller lighter can, basically a 22lr can vs a big heavy steel one for a full powered 223. Just something I like to play with, Im retired, have alot of time on my hands. Have a mold on the way to see about subsonic in my 8mm M48. I threaded the barrel on my old Spanish mauser in 308, and worked up a subsonic load for it.

[Lloyd Smale]

I wouldn't worry about them sticking in the barrel. Ive been fooling with trying to get a 100 grain bullet subsonic in my ARs. Its a very long cast bullet with no lube groves and pc coated. Now that bullet has a lot more friction going down the barrel then any 60 grain bullet would. I wouldn't run it at 600 fps but Ive shot a pretty good pile of them in this experiment at 1000-1100 and never stuck a single one. I'm not doing well though finding a load that stays subsonic and runs the action. Closest ive came is with 4895. I got it to eject with subsonic loads but the bolt doesn't come back far enough to grab another round. Is so close though. Bump it another 1/2 grain and its no longer subsonic. I'm not done trying though. Ive tried 6 powders so far and have 4 more to try today. Bottom line though is that it would be easy to get subsonic in a bolt gun with any 22 cast bullet and with the price of 22lr today id bet it wouldn't be a bit more expensive to shoot. Especially if you did it with a fast powder like bullseye ect.

[luvmy40]

Lloyd,
Try running a 300 aac recoil spring and buffer. That may be enough to get your load to feed.

[Electric88]

I was not aware there was a specific recoil spring and buffer for 300blk. My 10.5" 300blk uses the standard buffer and spring.

I almost would have guessed a low mass buffer/spring set-up to cure this problem, but that's just a guess.

[Lloyd Smale]

problem is that if a guy uses a lighter spring or buffer you are going to end up have problems with having enough power to reliably chamber a new round. The 300 blackout develops more pressure at subsonic levels due to its heavier bullet. I thought of your cure myself but guys that have tried it tell me its not the answer. Not that it isn't worth a try though. I don't know what the problem is. Maybe its something Elbert Einstein might have a better answer to then one of us handloaders but I tried re17 and re19 today with the same results. I get within a grain of powder of the gun running but that grain gets me supersonic speed. Re17 was subsonic eject the old brass but wouldn't pick up a new one at 12.9 grains. at 13 it ran but was supersonic. Same thing with 19 at 13.9 and 14. One other major stumbling block here is crud. After 10 or 15 rounds you have unburned powder all through the action that gums up the trigger mechanism and gets in the chamber and makes chambering harder. When and if I find a load that runs its going to be right on the ragged edge of working and not working and if it doesn't run a 30 round mag without a hiccup do to fouling what good is it.
Lloyd,
Try running a 300 aac recoil spring and buffer. That may be enough to get your load to feed.

[ikarus1]

there is the 60gr Sniper Sub Sonic 22LR from Aguila. Works well in a suppressed AR with one of the CMMG adapter setups. the 60gr works well with a 1-9 twist gun.

[luvmy40]

http://www.davidtubb.com/ar15-buffer-spring-stainless

http://www.brownells.com/rifle-parts/receiver-parts/recoil-parts/recoil-springs/300-blackout-carbine-buffer-spring-prod56149.aspx

OK,
I found several .300 AAC springs but no "AAC" buffer. You could run an H or H1 instead of an H2 buffer with the lighter 300 spring. If they feed and chamber the 300 Blk they should feed and chamber a.223/5.56

The question is will the sub sonic .223 load move even the lighter buffer assembly far enough to strip a round or lock back on an empty mag?

[luvmy40]

problem is that if a guy uses a lighter spring or buffer you are going to end up have problems with having enough power to reliably chamber a new round. The 300 blackout develops more pressure at subsonic levels due to its heavier bullet. I thought of your cure myself but guys that have tried it tell me its not the answer. Not that it isn't worth a try though. I don't know what the problem is. Maybe its something Elbert Einstein might have a better answer to then one of us handloaders but I tried re17 and re19 today with the same results. I get within a grain of powder of the gun running but that grain gets me supersonic speed. Re17 was subsonic eject the old brass but wouldn't pick up a new one at 12.9 grains. at 13 it ran but was supersonic. Same thing with 19 at 13.9 and 14. One other major stumbling block here is crud. After 10 or 15 rounds you have unburned powder all through the action that gums up the trigger mechanism and gets in the chamber and makes chambering harder. When and if I find a load that runs its going to be right on the ragged edge of working and not working and if it doesn't run a 30 round mag without a hiccup do to fouling what good is it.

Try a faster powder? Would a smaller charge of L'il Gun or 4198 or H335 be cleaner without risking detonation?(would detonation even be an issue in a rifle chamber?)

[Lloyd Smale]

ya but I'm sure it wont run the action either.
there is the 60gr Sniper Sub Sonic 22LR from Aguila. Works well in a suppressed AR with one of the CMMG adapter setups. the 60gr works well with a 1-9 twist gun.

[ikarus1]

ya but I'm sure it wont run the action either.
Thats what the CMMG adapter does....doesnt need to move the buffer

[ikarus1]

http://www.cabelas.com/product/CMMG-LR-AR-Conversion-Kit/753246.uts

[Lloyd Smale]

tried unique, hero, hs6, 4227, 110, 1680 4198 335 exterminator, tac, on the faster side 4895, 4064, re17 and re19 for mid range powders and re25, and 860 on the slow side. Ones that came the closest have been re19, re25 and 4895. the two reloader powders are just to dirty burning so still the closest thing to success is 4895. the 300 blackout probably isn't going to take as much to insure reliable chambering as its got loads with fairly clean burning powders so the chamber doesn't get all crudded up in a few rounds. That and it gums the heck out of the trigger mechanism so bad that you about have to pull it apart and clean it because spray cleaners do get it all
Try a faster powder? Would a smaller charge of L'il Gun or 4198 or H335 be cleaner without risking detonation?(would detonation even be an issue in a rifle chamber?)

[Lloyd Smale]

ive got a smith ar22 if I want to run 22lr. subsonic. the idea here was to get my 223 rifle subsonic with this 100 grain bullet. With a bullet that heavy its power level would be in a different world then your typical 22 subsonic load. Ive tried those 60grain lr loads and all of them tumble out of all of my 22s even at 25. I should say all. Ive only tried them in 3. my 1522 smith my takedown 22 ruger and my 16 inch bolt threaded savage. dismal accuracy in all three of them. I sure hope that 22 conversion uses a 1 in 7 twist or your not going to be happy. Especially at the price they want for them. Better deal is those norma tac 22s they are subsonic in all of my guns and run them too and shoot real well at a cheaper price. Then if your starting like me with a 223 suppressor which is build a lot different then a rim fire suppersor youll find that the 223 suppressor doesn't quite lr's down near as much as a dedicated 22lr can will.
http://www.cabelas.com/product/CMMG-LR-AR-Conversion-Kit/753246.uts

[ikarus1]

The aguila SSS are optimized for a 1 in 9 twist barrel, and most 22lr are most happy with a 1 in 16 like most 22lr rifles

[luvmy40]

Well, I'm out of ideas!

[Tackleberry41]

All the 22 lr set ups you have to decide, heavy subsonic or not. The fast twist barrel that makes those 60gr Aguilas work, may not like anything else. Gun that likes other 22 wont shoot the 60gr.

No idea on the drop in set ups for an AR on what they use for rifling, yea it would depend on the barrel in the rifle. But they still need some sort of barrel to take up the extra chamber. Cant imagine going from one twist to another is good for accuracy.

Seems if your that close to getting an AR to run subsonic 223, you need to look at the gas system. A bit more gas and it might cycle, or maybe a short one like the 300 does. Where the gas port is pistol length, you would get more pressure to cycle the rifle. Obvious problem is it would be over gassed for regular 223.

I know the obvious solution is some sort of chamber adapter, problem is any I have seen arent rifled, so you have a long throat before it slams into the rifling. It didn't work very good in my 45colt/410 set up. Way it is now, I can simply swap the mag for sub/supersonic. A 223 can will work sub or super. Its a Mossberg bolt gun that uses AR mags. Im going to lay out the cash for a 70gr mold from NOE soon. Have considered reaming out my lyman mold to get rid of the lube grooves, I powder coat, little more weight.