Going from a 12.5” to a 16” need buffer change?

[rocsteady]

With the pending pistol brace shenanigans the ATF is thrusting upon us, I would have been in a bit of a pickle had I not lost my 12.5” barrel, Troy A4 Other in that unfortunate boating incident in the bay.

Before said freak, rogue wave-induced disaster, I was thinking of changing the upper from the 12.5” that came with the “Other” to a BCM 14.5” with a mid length system so as to not run afoul of this wonderful and undoubtably effective legislation the ATF is somehow passing from their position as the enforcement arm of the lovely and talented democrats in DC…but I digress.

Question would have been if I would have had to change the buffer with the barrel now going to be 2” longer? Is this something that’s a common knowledge deal, something you can calculate, or something you have to do by trial and error if one was so fortunate, unlike myself, to have a lower around that was in need of a mate?

[grizzman]

It depends on what buffer you had been using with the 12.5" barrel, what spring you had been using with the 12.5" barrel, the 12.5" barrel's gas port location, the 12.5" barrel's gas port size, and the gas port size of the new 14.5" barrel.

There's a very good chance that the 14.5" will allow the AR to run fine with whatever buffer and spring are currently installed in the lower assembly.

[Sidneyious]

H1 and a blue springCo spring should be fine.

Or just get a mock xm177 moderator muzzle device and p/w that to the 12.5

[ChattanoogaPhil]

I recently purchased a BCM 14.5 mid length upper and had asked BCM their recommended buffer and spring. H buffer and standard carbine spring. I’m using an H buffer and Springco blue. The rifle reliably locks back and has a 4 o’clock ejection pattern. I only shoot M193, M855 and IMI 77.

[markm]

All correctly gassed barrels should run fine on the H2 carbine, Rifle buffer, or Vltro a5 system. No springco nonsense for me.

[settingsuns]

I never have. I would argue gas length compares to overall barrel length is more relevant.

[markm]

I never have. I would argue gas length compares to overall barrel length is more relevant.

With the correct gas port size too.

[rocsteady]

Received responses from both BCM and Troy and both were of the same opinion as you guys, that it should be just fine.

From BCM: "Thank you for contacting us. When running a 12.5” upper group we recommend a H2 buffer with a mil-spec carbine action spring. If you are changing to a 14.5” upper group, you may need to swap to a lighter H buffer depending on how hot your ammo is."

From Troy: "Thank you for reaching out to Troy Industries. The buffer system should work with no problem for you. If you have any questions please feel free to reach out to me."

[ViniVidivici]

I run H2s in everything.

With normal milspec type springs, that is.

It's perfection, across the board.

[markm]

I run H2s in everything.

With normal milspec type springs, that is.

It's perfection, across the board.

You need a springo with a blue end, red tip, and orange middle!! :rolleyes:

[ViniVidivici]

I know, go Gucci or git kilt in dah streetz!