.308 or .300BLK for Compact Bolt Action With 10” Barrel

[Ty17]

I’m looking into building a .308 or .300BLK bolt action gun with a folding stock and a 10” barrel. I plan to use the MDT LSS chassis and a left handed Tikka action (all of my rifles are Tikkas and I want to keep it that way). I’m torn between buying a .223 T3x and then buying a new barrel or just going with a .308 T3x and having the barrel cut and re threaded. I will only ever shoot subsonic ammo through it and it’ll be for hunting hogs. It’ll be suppressed. I want it to be very quiet so that eliminates an AR. The ammo for both is about the same price for the rounds I’ll be hunting with. What are your opinions on this? I know .300BLK was designed for suppressed short barrels. I guess my question is, will a 10” barrel on a .308 with a 1:10 twist perform the same as a 10” .300BLK 1:7 barrel? It would be cheaper to go the .308 route by $250-$350 (cut and crown/thread vs a new barrel).

 

[Tinkersmith]

The 1:10 twist is not ideal for stabilizing the heavier subs. It might be fine, it might not. You would want to test and confirm stability with all ammo before shooting suppressed. Its a good practice anyway.

I like .300 Blk, I'd do that, but that's me. The light weight supers aren't to be underestimated either and are better suited to that short barrel as well. Plus, if you hand load, you'll never get bored with .300 Blk.

 

[Robobiss]

My understanding, having only messed with subsonic 308 a little bit, is that there’s just too much volume in the case to get super consistent ignition without an unnecessary amount of effort. It’s a lot easier to get consistent ignition (and pressure, and velocity) with the blackout with like half the case volume.

My experiments with 308 subs was with H4895 and I wasn’t impressed. But that was with an 18” barrel, perhaps it would be different with a shorter barrel and thus a larger powder charge. I couldn’t get it to make enough pressure to blow the neck out to seal off the chamber so I was getting gas, unburnt powder, and other crap coming back into the action and my brass was all sooty. Didn’t even bother gathering any legitimate data about how well it was (or wasn’t) shooting. I have heard however that trail boss is THE ticket for 308 subs. It was unobtanium when I was messing around with them.

One benefit of the 308 is that when you want a “real” gun (supers) and want to make some stuff happen (I believe I’ve seen Form comment this before) you have it. If it’s strictly 100% subs then this point is irrelevant.

 

[coyotekilla]

I tried a ruger ranch and 300bo. Accuracy was fine inside 125 yards or so, but that was the limit. They drop so bad you will need a rangefinder. Hornady subx was the ticket, but it was very dirty, and their bullets arnt very consistent weight wise. Ended up selling the rifle, dies, and abandoning the whole 300 blk out project.

If I had to do it over again, probably a supressed big bore lever gun in 357, 44, or 45 colt. Suppressed, with cast bullets.

 

[bigunit]

Just to complicate things, i would throw 350 legend in the mix. So many ammo options out there and the sky is the limit if you reload. Can also single feed 9mm ammo for some fun plinking.

 

[SBR Sarge]

Do the 300blk out of the two you listed. But I think you could do better still.

Look at the new 338 ARC. More consistent SD due to fuller case fills of powder.

And I shoot 350 Legend out of AR SBRs to good effect on whitetail deer.