Have any of you guys dealt with any subsonic .223 loads?  I've been trying to do some research and can't find very much on the subject.  What can be done to get consistent velocities?  Do any of you use case fillers, and if so do they have any negative effects on a suppressor?  What other negative effects arise from shooting subsonic loads through a suppressor (other than baffle strikes from non-stabilized bullets).  Powders, bulletts, what to watch out for, etc??  Any info would be appreciated.

If you're using an AR, subsonic won't cycle it.

I realize I would have to cycle the ammunition manually.  I'm more concerned with getting consistent velocities (shooting uphill and downhill) and whether or not subsonic ammunition has any negative effects on a suppressor.  I’ve experimented a little using Unique powder in military cases, but I get inconsistent velocities when shooting at different angles due to the small amount of powder moving around in the case.  Any ideas?

Call Sierra, they will have some loads for you. I've got them in my file somewhere, they use Accurate Solo 1250 powder.

There are some subsonic loads that will cycle the action of an AR. They are insanely expensive, EBR makes them.

ETA, there is an outfit that makes reduced capacity cases for .308 for consistant subsonic performance but I've never seen anything for .223 since you basically are dealing with rimfire level ballistics.

I posted a thread on this subject on www.silencertests.com
I spent a little bit of time playing with this project.
I used 77 grain SMK bullets as well as 100 grain bullets. There are also loads listed in that thread for 55 grain bullets.

i see a few different bullet weights and powders used but no one has listed a specific formula, are there any?

lets say it dosent have ot be totally subsonic just near, that would still mean reduced sound correct? well nm thats a stupid question the sonic boom sounds the same no matter if you go over the limit by 10fps or 500fps

so would it work to possibly machine a custom case or set of cases that have smaller interiors and loading them with less powder...

what would the lbottom limit be without getting a bullet stuck in the barrel

If you are talking about the thread I was posting in, then yes, there are charges/powders/and bullets listed.
I basically posted everyday for a few days as I loaded ammo and then shot the ammo over a chronograph. What I was looking for was the load that went the closest to the speed of sound without going over it. I did this in the middle of the summer in approx. 110 degree temperatures.
I was successful in developing a very nice load using Trail Boss Powder. It completely fills the case in a load that is subsonic. No need for fillers or modified cases.

I don't know if you can link to that board or not since you have to log in to read the forum, but here goes a try. The thread is entitled, Trail Boss in .223 subsonics???
http://www.silencertalk.com/forum/viewtopic.php?t=3088
Here is the other thread I participated in called, .223, 100 grain, subsonic ammo loaded with Trail Boss http://www.silencertalk.com/forum/viewtopic.php?t=4632

The trail boss is a good powder for the sub-sonic loads.

I found some TTI Armory .223 subsonic 55gr FMJ Moly.  Anybody ever try this stuff through a can?  I bought a box of it just for shits and giggles.

Steve

444, I noticed your first try with H4895 was with a 16" barrel. Do you think it would be subsonic using a 10.5" barrel? I only ask because I have some H4895 and there is no local supplier of Trail Boss.

Quoted: I found some TTI Armory .223 subsonic 55gr FMJ Moly.  Anybody ever try this stuff through a can?  I bought a box of it just for shits and giggles. Steve

Nice and quiet, you have to hand cycle the weapon, but on my M4 with my M496D, it was quieter than my Mosquito with my Pilot on.

When I first got my silencer, I wanted a subsonic 5.56 round.

After ALOT of posts on the subject over the years, I can say affirmatively...There are EASIER ways to use an AR15 to fire subsonic rounds than to try and manufacture a round yourself.

9mm.

I shoot 147 grain subsonic 9mm in a suppressed AR15.

It cycles, it is consistent, it has better wounding potential, and it has proven itself in the taking of game.

My 9mm in 16" config will clover leaf a group of three rounds with iron sights at 75 yards.  

147 grains at .38 in diameter beats a 55 grain .223 anyday of the week.  The action cycles, the gun is ready for follow up shots, and the ammo is sold at Wal-Mart.

Instead of beating your head against the wall, searching for loads, trying to find a consistent performer... buy a 9mm upper.  Suppress it. Enjoy.

I have taken deer, hogs, coyotes with my 9mm subsonics.  

TRG

Iv'e got 5 pounds of TrailBoss waiting at home. Now i jsut need to get home so i cna experiement.

Quoted: 147 grains at .38 .355 in diameter beats a 55 grain .223 anyday of the week.  The action cycles, the gun is ready for follow up shots, and the ammo is sold at Wal-Mart.

Fixed it for you.

If you're wanting to shoot subsonic through an AR, just get a .22 conversion and use Aguila SSS.  A subsonic 60 gr. .22LR hits the target just the same as a 55 or 62 gr. subsonic .223.  Ammo is much less expensive and easily available.  

OTOH, half the fun of handloading is working up loads.  If that's what you want, then go for it.

Quoted: I found some TTI Armory .223 subsonic 55gr FMJ Moly.  Anybody ever try this stuff through a can?  I bought a box of it just for shits and giggles. Steve

 IT'S REAL QUIET (awc raider) !

Quoted: 444, I noticed your first try with H4895 was with a 16" barrel. Do you think it would be subsonic using a 10.5" barrel? I only ask because I have some H4895 and there is no local supplier of Trail Boss.

I don't know if it would be subsonic or not; but, if you re-read that post, I called the powder manufacturer and they said the load was unsafe. Don't try to be cheap: buying a pound of powder isn't worth blowing up your rifle.

Sure, you can use a 9mm or a .22LR upper to shoot an AR15/M16 with subsonic ammo. I have a suppressed 9mm upper, an LRM M169. However, this is NOT what I was trying to achieve.
If you have a good subsonic load in .223, you can have a few rounds or a magazine or whatever in your kit. You carry the rifle and shoot the rifle with your normal defensive/offensive/hunting load with the sound attenuated dramatically by your suppressor. AND, if the occasion presents itself, you have the ability to fire a nearly silent shot if need be simply by switching ammunition; which can be accomplished in seconds if  you have that ammunition already loaded into a magazine.
Having to change uppers (at least) is not a substitute.

Quoted: Quoted: 444, I noticed your first try with H4895 was with a 16" barrel. Do you think it would be subsonic using a 10.5" barrel? I only ask because I have some H4895 and there is no local supplier of Trail Boss. I don't know if it would be subsonic or not; but, if you re-read that post, I called the powder manufacturer and they said the load was unsafe. Don't try to be cheap: buying a pound of powder isn't worth blowing up your rifle.

Unsafe? What did they mention was unsafe about it? How can having too little powder blow up your rifle?

Not arguing, just curious.

Yes, having too little powder in your rifle (the wrong kind of powder, slow buring rifle powder) can blow up your rifle.
The powder detonates instead of burning.

Call Hodgdon and talk to them about it. Powder and bullet manufacturers are terrific to deal with. They all have tech. help lines where guys that really know what they are talking about will be happy to discuss any handloading problem you might be having. In this case, they even advised me to use a powder manufacturered by a different company.