300BlkTalk

So I have been seeing 6" 300 Blk Barrels out there recently.
It sure would make a compact pistol or SBR!
I have a 7.5" 1:7 twist that shoots both Subs & Sups pretty well.
Would a 6" Barrel be at all practical for either Sups or Subs??
Any of you guys have any experience with a 6 incher? (Barrel that is!)

I don't have experience with a 6 inch 300blk barrel. However I do with 7.5 and a 3.75 inch 300blk barrel.

Practically speaking its usefulness will only be limited by what you want to do with it.

If you are wanting to stay with supersonic loads in a short HD/enty weapon, I suggest 9 to 11 inch barrel. You can of course go shorter but at the loss of velocity of course.

If you want to stick with Subsonics, you can go as short as you want if you hand load. The load can then be tailored to your barrel length.

My plinking sub load for the 3.75 inch is a 155gr cast powder coated bullet. But even with a heavy duty 10 inch suppressor it is not very quiet at all. I don't have sound measuring equipment and I have tinnitus really bad but even I can tell it is pushing the sound safety threshold. There is a point of diminishing returns on suppression the shorter the barrel is.

Having said all that, I think 6 inch is close to the perfect length for a subsonic compact gun.

I built a six inch just to see if it would work.

Yup. It does. Supers are 100% with or without a can, subs are 100% with a can and work most of the time without a can.

Both group well, too.

I thought I chrono’d some loads through it but can’t find any on my laptop, but gds’s reply is spot on.

Bottom line, for a short, compact, maneuverable short range setup it is wonderful.

I did not notice enough difference in maneuverability between a 6.5” barrel and an 8” to justify the increase in noise. For me it was more important to be able to shoot without hearing protection inside a building, than not bang the end of the suppressor on something.

I chose to go with a shorter, better suppressor to reduce overall length. The key here tho was handloads. Nothing available off the shelf that I know of would even get me to consider a barrel that short.

Three part article series starts with part 1 here
https://loadoutroom.com/50929/ultra-sho ... up-part-1/

I ran 5 different barrels, 4.75"-6.5" for chrono data and accuracy with ~10 different ammo types.

Now that the series is done, I'm keeping the 6.5, which was nearly identical in performance to the 6" and 6.25". Each barrel preferred one type of ammo more, and another less. I like the barnes 110's, so am keeping the barrel that shot best with those

Thanks guys!!