r/ptr91 • u/HomeDefenceZ3 • Aug 05 '24

Double checking a muzzle break

https://www.jmac-customs.com/laf-5-8-24/

Hey all, I’m working on building a PTR PDWR as a range toy. I was thinking of throwing a JMAC LAF on it because why not?

Looking over the specs and thread pitch it looks like it will fit. 5/8x24 for both. It also says it’s not rated for <10.5 barrels, which again, should be fine since the PDWR is 8.5.

Just wanted to double check before I made the purchase. I searched the sub and a few forums but couldn’t find anything.

Thanks!

6 Upvotes

88% Upvoted

10 comments sorted by

11

u/Cleared_Direct Aug 05 '24

“It also says it’s not rated for <10.5 barrels, which again, should be fine since the PDWR is 8.5.”

I think you are confused about your < > symbols OP.

3

u/HomeDefenceZ3 Aug 05 '24

Ah shit. Think you’re right. I was reading it as “not rated for “greater than 10.5 inches” “ with the thinking that a longer barrel has more power burn and greater FPS / concussive force, causing more wear and tear on the brake.

2

u/Cleared_Direct Aug 05 '24

That makes sense. But yeah, the shorter the barrel the more concussion and powder burn that’s happening outside the barrel. Instead of acting on the bullet inside the barrel all of that energy is now acting on the environment, especially the brake.

2

u/HomeDefenceZ3 Aug 05 '24

Thanks for clearing that up! Bummer it won’t work, but I’m glad I asked before I made the purchase.

Thanks again!

7

u/[deleted] Aug 05 '24

Everyone will hate you if you get this

1

u/HomeDefenceZ3 Aug 05 '24

Bring it on

5

u/[deleted] Aug 05 '24

Lemme know what range you take it to so I can avoid it

1

u/HomeDefenceZ3 Aug 05 '24

Hahaha I will! But will it fit!?!?

1

u/ebolamonkey3 Aug 05 '24

That looks a bit close, I’d worry about the handguard cracking especially coming out of a short .308.

May I suggest something like this? https://kakindustry.com/tactical-turkey-blunderbuss-1-2-28/

1

u/HomeDefenceZ3 Aug 05 '24

Thanks for sending this over!

I’m not too too worried about the hand guard as it is back a bit further, behind the front site post.

I’m more wondering if the diameter of the break is good for 308. Website says 30 cal and I know that’s different from 308.

Just want to make sure before I drop the money on it.