.308 Win Subsonic

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Going to build a 16” bolt gun in .308 Winchester. Planning on suppressing with a Dead Air Sandman S. Anyone rolling their own subsonic loads for the .308 Win? If so, what powders, bullet weights, and any other tips or pointers?
 
175gr SMK, 7.5GR titegroup 20" bbl.
1/10 twist. Gives me 2" groups at 100yds.
You can basically use 300blk sub data.

Lil' gun is decent also but use a 220gr.
Stabilization isn't great past 100yds with any of the 308 subs but it doesn't have enough ass to do anything serious anyway.
 
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Try giving castboolits.gunloads.com a search for a load. There lots of guys using cast bullets at low velocity in 308 over there. You will probably get more recipes than you want.
 
clay_fv said:
If I were going to do that, I'd use a bullet designed for subsonic flight. Hornady 190gr SubX or Berry's plated 220gr. Every 308 bullet is designed for far greater velocities.
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Yes. Bullets designed for subsonic expansion or a good meplat. It's one reason I have up on the .300 Whisper platform way back when, before they started making low velocity .30 cal rifle bullets.
 
If you are going to buy a barrel, see if you can get a faster than normal twist rate - that will help stabilize heavier bullets and give you more options than a 1:10 twist.

I would look to the heavy bullets intended for 300blk.
 
You may want to look into a lighter gun with a mini action. 350 Legend, 300BLK, 450 BM.
I built my 1st 300BLK to hunt, then I learned about the poor hunting ballistics. I picked up a Howa 450BM for subsonic hunting.
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Average Joe said:
Going to build a 16” bolt gun in .308 Winchester. Planning on suppressing with a Dead Air Sandman S. Anyone rolling their own subsonic loads for the .308 Win? If so, what powders, bullet weights, and any other tips or pointers?
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Hunting rounds or just shooting paper and having fun with how quiet it is?

I use an Xtreme bullets 150gr plated flat point (they work in my .30-30 also) over 8.2gr of Trail Boss (I think this is the correct #…it’s definitely under 9 grains). It’s fun to shoot at steel ways off

I havent done a load with a Hornady or Lehigh subsonic hunting bullet yet
 
11B CIB said:
Hunting rounds or just shooting paper and having fun with how quiet it is?

I use an Xtreme bullets 150gr plated flat point (they work in my .30-30 also) over 8.2gr of Trail Boss (I think this is the correct #…it’s definitely under 9 grains). It’s fun to shoot at steel ways off

I havent done a load with a Hornady or Lehigh subsonic hunting bullet yet
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Looking for both paper punching and hunting. I didn’t even think about the Xtreme bullets for range use, great idea.

Did you drill the flash hole to make it larger? I’ve read that doing so really helps with the ignition of the trail boss powder.
 
Average Joe said:
Did you drill the flash hole to make it larger? I’ve read that doing so really helps with the ignition of the trail boss powder.
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I can safely say that Trailboss can be sensitive to different primers. In my testing of Trailboss in 45acp, I saw almost 200fps difference in velocity between large and small primers. I don't know if drilling out the flash hole would have helped, though.
 
Average Joe said:
Going to build a 16” bolt gun in .308 Winchester. Planning on suppressing with a Dead Air Sandman S. Anyone rolling their own subsonic loads for the .308 Win? If so, what powders, bullet weights, and any other tips or pointers?
Click to expand...
I'm still putting together .223 bolt gun and finding a barrel maker without a 2-4 month lead is hard. I found this guy out west that uses Xcaliber barrel blanks. I called him up, really nice guy and we talked about what I wanted, and he made recommendations and told me to put the order in and shipped it the next day. He would talk to you all day if he could. Said things have slowed down as gas went up. I didn't want it long for hunting so kept it a 20" SS blank with 5R rifling in a sendaro taper (which is a bit heavier than normal sendaro so I had to inlet the stock more) using the Remage nut method. The remage nut method is pretty easy, you just need go/no go gauges and a wrench or his nut wrench. I have not shot it yet so I don't know how it preforms but there seems to be good reviews out there. Pacific Tool and Gauge bought all of the last Remington 700 and Model 7 receivers when they collapsed years back and now sell them at around $550-600 for a blueprinted one if you have to have a rem action.

I bought into the 300 blk out early but yes a stated above good preforming bullets at Sub velocities were hard to find. Now the choice is better and more are designed for sub velocity hunting as well. Most are solid copper. For 308, filling the case enough to get a good consistent burn at sub velocities will be the main concern. I think batteryoaksBilly's friend Michael has a few good write ups on 300blk/308 subsonic for hunting and bullet choices.
 
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Slacker said:
Trail boss was a waste of my time in subsonic 308. Such inconsistent velocities.
Titegroup was a clear winner.
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What grain bullets and powder?
 
Average Joe said:
Looking for both paper punching and hunting. I didn’t even think about the Xtreme bullets for range use, great idea.

Did you drill the flash hole to make it larger? I’ve read that doing so really helps with the ignition of the trail boss powder.
Click to expand...

I did not drill the flash hole, but I can go back and check the brass. I don’t know on the Federal M1A marked brass I’m using for subs how the pockets compare to say the Nosler brass I use for hunting loads and the FGMM I have for match use but I can check tonight

I wasn’t getting precision level accuracy with the bullets but they all stayed on a paper plate at 200yds which was fine with the shenanigans I was participating in. I didn’t try Titegroup just because everything online said the case capacity difference between the two made Trail Boss seem like a winner. I’ve been using CCI #200s for it but I might try some Federal GMM LR magnums

I did use TiteGroup for .223 subs with 55gr FMJs and SPs just for fun and it worked fine. 3.1gr with 2.240”/cannelure length
 
FWIW I've been running .309 90gr XTP's over Trail Boss in a BLK for a few years now. No problems with ignition. But not a lot of volume shooting with that. Just hunting. It's consistent enough for squirrel heads when I want small game and pigs/deer don't want any more of it, either. Placement rules with small subs.
Used TB in the original 700/308 set up as well. Fills the case nicely. For my uses the deviations I got in velocity weren't enough to fret over at the ranges I used it for. But I didn't see the sense in continuing with that big of a case to shoot subs, so we rebarreled to somethin else. But while I was using it I ran 180gr RNSP mostly. IMO a 16:1 lead bullet in whatever weight a fella felt he needed would be a good option. Something soft-ish with a bit of easy expansion and a flat nose would prolly be good.
If I had it to do over again I'd have went with some kindof smaller case 45. Throw a big, slow, fat rock. :cool:
 
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