Couple of subsonic .223 questions

[ShowroomShine]

Shooting this out of a 16" AR Carbine. Dont need it to cycle the action. I'm new to the reloading game and want to know a few things.

First off, if I have a good supply of Unique can I use this as a good subsonic powder for my .223 loads? If not unique, what other powders would be best for making a subsonic load?

If I want to make .223 subsonic, I am assuming the heaviest bullets would be best for making a subsonic load? What weights or styles would you suggest?

And finally and possibly the most important question, how quiet will it be? I am in a situation that I need the relatively low noise of a .22LR/.22WMR, but the power of something bigger. I know under ~1200fps it wont have a sonic crack, but how loud will the round still be at the rifle? No hearing protection loud, must use hearing protection loud, startle the neighbors loud?

Thanks in advance for the help.

 

[ATCDoktor]

If you're new to reloading, subsonics in a centerfire rifle case (with jacketed bullets) is not the place to start.

Strange things happen to jacketed rifle bullets of certain designs (in certain barrels of specific rates of twist) when you slow them down to around 1000 fps.

A normally aerodynamic, super accurate projectile will turn and fly base first to the target when launched at the speed of sound (depending on barrel length and rate of twist)

I would go here:

http://www.silencertalk.com/forum/viewforum.php?f=68

and do a search for what you want to know.

These guys (as I have) have already done the work and have a wealth of knowledge on all things subsonic.

I know under ~1200fps it wont have a sonic crack

The magic number reference the speed of sound is 1050 fps anything faster than that and you will most likely get the sonic crack.

That said, this speed is variable with temprature and altitude so your mileage may vary (the colder it is the easier it is to have your subsonics "crack").

 

[kingmt]

I agree it might not be the best way to get your feet wet unless you try Trail Boss but Unique should work also. I use a powder the same burn rate as Blue Dot which is my favorit. You can even use Red Dot but if you make a mistake it can be catastrophic. Light for twist rate bullets work best & even turning the bullet backwards even improves groups. I suggest you spend some time researching this before you start down this road.

You can shoot without ear muffs but I still suggest you use them.

Take every caution to ensure you can't make a mistake. I keep my cases neck down to ensure the case is empty until I drop the charge then seat a bullet before anything else is done.

 

[mtrmn]

I guess you are wanting to quieten down the AR as much as possible WITHOUT a suppressor? If so, it's still gonna be fairly loud but I don't know how bad.
Like suggested by others, look on Silencertalk, and Snipershide for suggested loads. Trailboss is by far the best powder for this purpose because it's so bulky in relation to weight. Some powders under some conditions will have a secondary explosion when they don't fill the case properly. I've never seen this but I don't want to either. 1 container (it won't be 1 lb of Trail boss) of powder won't break you.
Once you find a suggested load, you can start a little above that and work your way DOWN instead of working up like normal loads. Even without a chronograph it's easy to hear the difference between supersonic and subsonic. The bullet breaking the sound barrier is LOUD. I do not remember how loud the muzzle blast was on my 308 without the suppressor when I was working up my loads, but it was a good bit quieter than full power loads. You will still need hearing protection. WITH the suppressor my AR10 action opened about halfway and slammed back shut. This was the loudest part of the SUPPRESSED shot. It was real quiet, like shooting a BB gun or something.
Shooting FULL POWER loads with my suppressor sound just like shooting the 22LR or 22magnum you mentioned.

Now, when working on a load, you need to shoot a paper target up close and at distance to make sure your bullets are stabilized and making nice round holes. Also, anything over about 70 or 75 grains and the bullets will have to be seated too long to work with your magazines. I'd just work with whatever you normally shoot unless they won't stabilize.

DO NOT USE A SUPPRESSOR WHILE YOU DEVELOP YOUR LOADS-UNSTABILIZED BULLETS MAY CAUSE BAFFLE STRIKES AND DESTROY YOUR EXPENSIVE TOY. Only install a suppressor after you've proven your ammo to be stable.

Editing to add: Subsonic .223 loads will most likely NOT be any more effective than a regular 22LR and probably a 22mag will be MORE effective on game/varmints. I loaded subsonics for my suppressed 308 just for curiosity. I have NO PRACTICAL USE for them. You'll see how weak they are if you go through with this, and IF you don't have a suppressor for the muzzle blast you just as well break out your 10/22 to handle any varmints.

Maybe I'll get through editing this soon.........just trying to be as informative and helpful as possible.

 

[BeerSleeper]

I'd get the conversion parts to fire .22LR from it, and use subsonic .22LR ammo.

 

[kingmt]

"Secondary explosions, have to be seated to long to fit the mag, no better the8n a 22, 10/22"

Come on. Please do some research yourself.

 

[AMG04]

+ 1 to Mtrmn: Great Advise and good information.

Subsonic loads present more issues than they solve and offer very little practical use.

I have a CMMG conversion kit for my AR that shoots 22 lr (appx. $150). When shooting 60gr sss 22 lrs with my suppressor its very quiet! About as close to "Hollywood" quiet as it gets. I also shoot a bolt action 22 mag with the suppressor. The loudest noise is the bullet hitting the soda can or steal plate.

Another route you can take is getting an upper in 300 AAC blk. This offers factory subsonic rounds, but without a suppressor it will still be loud.

 

[redbullitt]

Trailboss will take lots of headache out. It is not clean burning by any means but it works very well since it is so fluffy. A double charge in a 308 case will just about be over flowing, so you would notice lol. It does a good job of being insensitive to position in the case, AND fills it enough that you avoid many of the ignition problems associated with pistol powders in rifle cartridges.

Pay attention to what barrel twist you are running as you may have stabilization issues. I have not done much 556 subsonic, but I do use a lot of sub 308. If you have a fast twist, the sub 556 could be very handy. As to those who say its just like a 22lr, no not always. With a fast twist you can get a heavy bullet going down range that YOU loaded AND that is a centerfire round. You should be able to get a good bit more consistency with it at longer ranges. If you have a slower twist, then it is a bit less handy since you can't spin up the heavier bullets.

As to bullets for the 556 I am not sure what I would try. In a pinch you can load spitzers etc backwards in 308 and it works pretty well.

FWIW I will say that the pests around here hate subs lol.

 

[carnaby]

Check out our new Bison Armory 6.8 subsonic. Accurate within the 150 or so max subsonic range. 200 grain bullets. Cycles with or without a silencer, and shoots full power 6.8 SPC ammo too.

 

[CMV]

I'd look at it this way - all standard pressure 230 gr .45ACP is subsonic & that's a lot less charge than you'd be using. Still pretty loud.

 

[helotaxi]

Lot bigger bore and a lot shorter barrel as well.

Hodgdon's lists subsonic .223 loads in their data using 55gn bullets.

 

[Ranb]

I loaded my suppressed AR-15 with Speer 70 grain bullets and 7 grains of WC820 (like H110) powder to get about 1050 fps. Accuracy was about 2-3 inches at 100 yards with a 1-8 twist. The action did not cycle at all. A 70 grain bullet at 1050 fps is almost twice as powerful as 40 grain bullet out of a 22lr at 1000 fps, but is much noisier due to the much heavier powder charge. It will be hearing safe without ear plugs though.

Any fast pistol powder will work fine. Start fast and work your way down to prevent getting a bullet stuck in the barrel. You will need a chronograph to develop the load, there is no way to do it without one. You need to be less than 1100 fps to ensure no sonic boom and more than 900 fps to ensure trajectory and power does not suffer. A 1-9 twist is good enough for Speer 70 grain round nose, use a 1-7 twist for a 69 grain HPBT. Check for keyholing at 100 yards before using with a silencer.

Based on my experience, the only firearms that are not loud are rifles using CB ammo (primer only rimfire), suppressed 22lr subsonic rifles and 22lr pistols with very effective silencers on them. All others are loud enough to bother the neighbors. Unsuppressed pistols with CB ammo hurt my ears as does any unsuppressed rifle with standard velocity or higher 22lr ammo or ANY centerfire unsuppressed firearm.

Ranb

 

[jmorris]

I am in a situation that I need the relatively low noise of a .22LR/.22WMR, but the power of something bigger.

You would be better off with a 9mm upper then, you are not going to be able to out do a load like the Aguila sss 60g .22 lr, with a subsonic .223, by much except in cost to make.

I don't know why you need the power of something bigger but if it's for an animal, even bullets designed to expand at normal .223 speeds don't do much at ss. On the other hand a 9mm 147 is going to have around twice the mass of a heavy .223 and be designed to preform at the speed your after. Bullet weight is the only way to control energy once you limit your self to subsonic. That's why rounds like the 458 socom exist.

 

[carnaby]

Subsonic 6.8 with a silencer is reasonably quiet. I shoot them without ear muffs, and I'm typically fairly noise averse. Without the silencer, the sound is a lot lower than full power, but still too loud to forgo earpro.

 

[carnaby]

Here's what 6.8 full power sounds like suppressed.

Here's the subsonic, 200 grain bullets, suppressed.

 

[Ranb]

Whenever I record, capture and upload suppressed and unsuppressed videos, they sound nothing like the real thing. The real thing sounds much better than playback on a computer or TV; you really have to be there to appreciate how well a silencer does (and does not) work.

Ranb