.223 subsonic loads with enough pressure to reliably function AR...
- Thread starter Meroh
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Quite a bit of info on the net, search for "subsonic .223 ammo that cycles"
HEAVY bullet, slower powder, maybe a lighter buffer in the rifle. Quickload would be a good tool to look for powder/bullet combos.
The people in the video use a 112gr bullet. : https://www.youtube.com/watch?v=ZmBycznn53U
I tried to do this with very poor results, I had the rifle cycle a few times but never consistently. I didn’t save the data as I was pretty frustrated when I was done. If you succeed please share your results. I moved to 300blk and never looked back.
Fast powder will boost chamber pressure but not give high velocity. But the gas port is mid barrel, where pressure has dropped.
Making sub sonic ammo is easy. Making it cycle the action is the challenge.
I would be more inclined to try a reduced powder charge of 4895 or Varget, to get more port pressure. maybe even 4350.
Two of my carbines are very over gassed. That would be the rifle I would try.
Making sub sonic ammo is easy. Making it cycle the action is the challenge.
I would be more inclined to try a reduced powder charge of 4895 or Varget, to get more port pressure. maybe even 4350.
Two of my carbines are very over gassed. That would be the rifle I would try.
This is something I'll try in the Spring.
The first thing I always do is see what others have done and reported. That said, anything that works in one rifle might not work, or will probably at least require tweaking.
Since you want subsonic MV's, unless you're running a fast twist (1:8 or faster) I'd avoid bullets heavier than 69 grs, and I'd start with 55's.
For powders, I'd probably use a slow pistol powder like 4227, a 4198, and a 4895, all of which work well with reduced loads.
The first thing I always do is see what others have done and reported. That said, anything that works in one rifle might not work, or will probably at least require tweaking.
Since you want subsonic MV's, unless you're running a fast twist (1:8 or faster) I'd avoid bullets heavier than 69 grs, and I'd start with 55's.
For powders, I'd probably use a slow pistol powder like 4227, a 4198, and a 4895, all of which work well with reduced loads.
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You are looking for low velocity and high pressure (to cycle the action). I think a heavy bullet is required. I would start with 80 and 75 gr bullets.
The engineering and R&D has been done for this already. Succesful commercial ammunition that cycles is available as we speak.
Slow burning powder produces higher port pressure,and more gas volume which in this case is necessary to cycle the action.
Slow burning powder produces higher port pressure,and more gas volume which in this case is necessary to cycle the action.
Thanks for the info, thoughts and opinions. My rifle is 1:12 x 20" Pistol/shotgun powder =faster burn; heavier bullet = more pressure, but lower speed. This is what I'm thinking too. I do realize that my rifling is slow, and may not stabalize a longer bullet.
I will not be modifying the gas port, as this rifle is a tack driver with my hot .223 55gr. loads; lighter buffer/buffer spring maybe?
I will not be modifying the gas port, as this rifle is a tack driver with my hot .223 55gr. loads; lighter buffer/buffer spring maybe?
These things have all been done before.
Can you share a load that is subsonic and employs a full or near full case of a slow powder with a 55 gr bullet that cycles a properly setup action?
Are we talking 4350-4831 or even slower? It's tricky as those powders work poorly at low pressures.
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It's been done but maybe not with the 55gr bullets. If there is a load that will cycle subsonic 55 gr or 62 gr bullets then I would like to see the data also.
Would be lucky to have half the powder burn in a reduced load of 4350 with a 55gr bullet, and it woulod probably still be super sonic.
Would be lucky to have half the powder burn in a reduced load of 4350 with a 55gr bullet, and it woulod probably still be super sonic.
