308 bolt action subsonic?

For those who haven't tried it, suppressed subsonic loads in a bolt gun are amazingly quiet. Like you can hear the firing pin strike the primer quiet. One of the only reasons loading subs in a .308 isn't so popular is about the fastest off the shelf twist rate for them is 1/10 (most .300bo's have a 1/7-8 twist). Most barrels with this twist should stabilize 208gn Hornady A-Max's out to about 100yrds before they start to keyhole. Some have had success stabilizing 220gn bullets with a 1/10 but most have not. Years ago I had a Savage Hog Hunter which is a 16" barrel and IIRC I used 10.5gn of Trailboss with a LR magnum primer. Didn't find a need to drill out the flash hole in the brass either. They ignited just fine, at least the couple of hundred I loaded and shot did. If your gun is a 20" barrel use about .5-1 grain less. Also I highly recommend you first set up a target at 5-7 yards and shoot without the suppressor first to check for keyholing. Having a baffle strike will definitely ruin your day.
 
Agreeing with the above post, the starting load of 10 gr of Trail Boss powder with a 150 gr cast bullet should do the subsonic job somewhere in the vicinity of 1100 some fps.
 
TMD,
What is meant by a "baffle strike", not familiar with the term and don't want to ruin the day. Does it have something to do with a suppressor?
 
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What is meant by a "baffle strike",
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A baffle strike is quite literally when the bullet strikes one (or more) of the baffles inside the silencer as it travels thru it.

At the very least it will damage that baffle. In a lot of cases the bullet is so destabilized by the strike it basically ricochets out the side of the tube. This totally RUINS your suppressor and most likely has made it a VERY expensive piece of junk.

All loads shoud be checked for stability WITHOUT the can on BEFORE shooting even 1 round thru the can.

Set a clean sheet of cardboard at about 25 yards. Shoot 10 rounds at different spots on the cardboard. You are NOT shooting a group. You want 10 separate holes to look at. Any bullet hole that is not perfectly round is a suspected instability issue.

If i get 10 PERFECTLY round holes i assume the load is GTG amd i'll shoot it thru my cans. ANY oblong hole and you need to go back to the drawing board. Shorter lighter bullet...faster twist..increase velocity, are all ways to improve bullet stability.
 
Keyholing is another word for the bullet not being stabilized when it leaves the barrel due to the twist rate not being fast enough for it.
 
Thanks for the explanation. I guess silencers are not legal in California so will not have to be concerned with that. Our astute politicians are influenced by the 1920 circa movies where bank guards are wiped out by bad guys with silencers screwed onto their .38 revolvers. Or as they would say, the silencer deforms the bullet which would prevent identification I suppose.
 
Set a clean sheet of cardboard at about 25 yards.
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I was taught to shoot literally 15ft in front of me to check for keyhole signs. I mean technically it would make the most sense to shoot point blank since you are checking for keyhole signs when it is leaving the barrel/silencer.

I usually check 25 yards after anyway before sending the target out to 50+ with a new load but I would call silencershop or someone to confirm your 25 yards. I assume some of them do well, but money is money and shooting a lot of 308 or 300blk eats the pockets clean if you're shooting factory loads :D
 
Baffle strikes can turn a few hundred dollars into scrap metal. I always confirm stabilization to avoid this.

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