308 bolt action subsonic?

T

taymag

New member
I am extremely unfamiliar with 308 rounds.

I have semi-mastered my 9mm and 300blk loads over the past few months thanks to you guys and want to get down to business with my Remington 700 308

Also, for people that shoot 308 suppressed, is it common to shoot 308 subsonic? Just looking for some direction... Thanks
 
is it common to shoot 308 subsonic?
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It is about as common as driving a 455 cubic inch hot rod as a golf cart.
Speed of sound is 1125.33 fps.
308 travels at 2 to 3 times that.
So you would need to go way up in bullet weight (220 gr +) and load way down on the powder. So the big question is
WHY?
 
I have a dumb question... why load a 308 subsonic instead of just using the 300 BO? Isn't the piece of lead leaving the muzzle the same? If the answer is "just cuz," then great. Good luck! I'd start with Trail Boss.
 
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Thats why I asked... To answer the huge WHY, even though it might not be practical, with a 15x scope on a 700 I am still better off than my 300blk with a red dot. Not saying I am going to do it, but ya...

So whats a common bullet to run? Seems like I saw a few "base line favorites" when getting to the bottom of finding my favorite 300blk and 9mm loads
 
More of a target bullet than just plinking, but if you are interested in accuracy go for the Sierra 168 gr HPBT. Will be somewhat more expensive however. But if just plinking is the goal, look for any inexpensive 150 gr bullet at your gun shop. And if interested in reduced loads, try to find Trail Boss powder and then ask the forum how to use it.
 
I load 308 both subsonic and full house.

I dont have my load data in front of me but i know my subsonic load is a 208Amax over Trailboss powder and clocks just a tick over 1000fps out of my MVP with my SDN-6 can.

WHY do i shoot subs in 308? Cause i can and its SUPER quiet. Most guys i know have a 308 bolt gun, but only a few have a 300 blk BOLTGUN. So instead of buying a boltgun in 300blk, they just shoot 308subs.
 
So instead of buying a boltgun in 300blk, they just shoot 308subs.
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And you can shoot cast bullets too! Does brass length get shorter when repeatedly shooting low power? I read that is a concern.
 
Seriously, a friend asked m e how to create subsonic rounds for his .308 to use with a suppressor, and everything I worked on for weeks of research came up a failure.

I could never find anything that looked safe and practical and accurate that actually could be throttled down to 1,100 o r less in h I s semiautomatic suppressed rifle, and nothing for a bolt, either. I would declare it to be impossible, but another person already said that it can be done. I'd love to learn the data and see targets and chronograph records to see how he accomplished the low pressure l ow speed problems and managed to get good functioning.

My friend gave up and bought a blackout. Nobody who worked on the problem could solve it and the gunsmith he used told him that it was impossible.

It wouldn't even be simple to tweak a gi carbine down to functional subsonic loads in a semiautomatic rifle with standard twist and chamber.
 
It was not sub sonic but close on a 308. I got into loading lead bullets for a 308 Ishapore 2A1 rifle. The load was from the Lyman lead book at around 1600 fps with a lead gas checked 190 gr with pistol powder. Thing turned out to be very accurate out to 100 yards and the recoil was similar to a 9mm carbine. Nothing more than an experiment and first time loading lead in a rifle caliber.
With a heavier bullet you could get closer to sub sonic.
 
You need to consult a cast bullet shooter. A lot of people load all manner of hunting rifles to subsonic velocities for range fun. My favorite is a .308 180 gr. cast lead bullet over 11 grs. of Red Dot.(that's over 5,000 loads from an 8 pound jug of red dot) No filler needed and the barrel life with this load is a couple of million rounds. It will ring steel with authority at 200 yards.

Google up "cast bullet for military rifles" by E.D. Harris. This article has data for jacketed bullets at this level of pressure.
 
I have done it for back yard plinkers. A cast and coated 150 with 11 grains of trailboss makes for a light plinker. Not anymore lethal than a 147 grain 9mm subsonic round and it costs more to shoot but then again I don't have a bolt action 9mm...
 
If you want to shoot 30 cal bullets subsonically, I suggest you talk to the folks at SSK industries. They are the originators of the Whisper concept (rifle bullets at subsonic velocities). A key to their success if a barrel twist of 1:8 or faster. A Remington 308 bolt usually has a twist of 1:10. This means you will NOT get accuracy with long subsonic bullets. If you want to play with short stubby bullets, they should be ok at slow barrel twists.
http://sskindustries.com/300-whisper/
 
If you are looking for a mild reduced recoil and reduced velocity load, using either cast or jacketed bullet with any rifle caliber, that is exactly what Trail Boss powder is intended for. Initially referred to as cowboy action shooting, the reduced loads provides quick recovery between shots. And especially with cast bullets barrels will last forever. Trail Boss powder is not all that easy to find however but if you can find some, it comes nine ounces to the can rather than 16. Here is how you use it. Determine where the bullet will be seated in the case and fill the case to that point and do not be concerned with grain weight of powder, just go by volume to where bullet will be seated to and it doesn't matter what bullet weight you are using. Loads will be safe with mild recoil. I know this sounds unusual and it is but this is what the powder was made for. Again, just put your scale aside and measure by volume, no chance of getting an overload. Fill the case to about where the base of the bullet will be after it is seated. And for .308 for example, doesn't matter if bullet weight is 150 gr or 220 gr or anywhere in between. Great for cast bullets. See if your gun shop has Trail Boss powder for a new dimension in shooting. Your barrels will appreciate it and your shoulder will also if loading for normally heavy recoiling rifles. The same goes for handgun loads and it is used the same way. Note that you won't find much reference to Trail Boss powder in loading manuals.
 
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Determine where the bullet will be seated in the case and fill the case to that point and do not be concerned with grain weight of powder, just go by volume to where bullet will be seated to and it doesn't matter what bullet weight you are using
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May not be subsonic at that charge. My cast and coated 150's were right on the edge of being supersonic at 11gns (about 60% fill).
 
For a little more information regarding starting and max loads with Trail Boss powder, see post #6 in current thread "new to reloading".
 
Looks like the starting load would about be subsonic and would be very wimpish. Wouldn't load more than two that way since most would want to immediately increase the load. Very little published rifle load data for TB powder it seems but the above link does provide some and includes one of my favorites, the .416 Rem Mag. However I don't know my grain weight since I just fill to the base of the bullet.

Late addition:
The chart from the above link shows 29 gr max load with a 350 gr bullet. Weighing my charges to the base of the bullet, weight for a 360 gr bullet and brass Remington case is 28 gr, and weight with same bullet and nickel plated Remington case is 27 gr. So there seems to be favorable agreement.
 
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Looks like the starting load would about be subsonic and would be very wimpish. Wouldn't load more than two that way since most would want to immediately increase the load.
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I agree that it makes a 308 wimpy but if you want subsonic, like the title of this thread, that's what your looking at as a solution.
 
Wow... a lot of answers in this thread, haven't checked it in a while.

What it boils down to on the WHY!!! is that I've had this brand new Remington 700 and have several 30 caliber silencers and wanted to make a cool bench rest setup rather than just blasting the 300 blackout... So basically some "quiet" variety. Ya, they still will quiet supers but there's something fun about subs and don't have anything with any reach really since my 300blk has a red dot and I don't really like shooting it from the bench. Not to mention I shoot cast mainly, not in the 700 yet but I would like to
 
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