BRT EZTUNE Gas Tubes

[Clint]

What's the round count up to on the tube?

Decided to take this gun apart and clean it today after 1,000 rounds of Tula 55gr steel and a bit of brass 62gr 5.56, all suppressed. Doesn’t seem too gross.

[1168]

What's the round count up to on the tube?

If its the same tube that was on this barrel before, and I think it is, it would be in the neighborhood of ~12k, but I haven’t been keeping a hard count.

[JediGuy]

I picked up a 12.5” carbine BSF barrel second hand (not used). It has a .875 diameter at the gas port. I emailed BSF to check port size, in case a BRT should be used from there start.

Their response: 0.082

That seems more than a full hundredth larger than equivalent 12.5” barrels. Will that supersize port decrease the lifespan of a BRT tube, if used?

[Clint]

We haven't seen any correlation of base port size to service life.

With the barrel ported that large(+50%), you'll definitely want a tube to settle it down.

I picked up a 12.5” carbine BSF barrel second hand (not used). It has a .875 diameter at the gas port. I emailed BSF to check port size, in case a BRT should be used from there start.

Their response: 0.082

That seems more than a full hundredth larger than equivalent 12.5” barrels. Will that supersize port decrease the lifespan of a BRT tube, if used?

[1168]

That’s a ridiculously huge port. Almost two hundo over. I haven’t seen any correlation with wear of the tube, although, I’ve noticed that a bigger base port seems it can run with a smaller tube orifice. Not a large enough sample size to prove that, just a small handful of anecdotes.

I’d put a .065 tube on it if unsuppressed, or a .057 to run with a can only.

[Wake27]

Yeah I think most 12.5s are coming around .065 or so. Don’t think I’ve ever heard of one larger than .070, so above .08 is insane.


Sent from my iPhone using Tapatalk Pro

[Dutch110]

.082 port size on a 12.5 is borderline negligent.

[JediGuy]

Update: I sold it.

[Clint]

Sometimes customer feedback just makes us smile.

David wanted to use a Griffin GP5 direct thread suppressor on his 10.5 upper, but was having issues.

it’s super over gassed A5H4/ green springco with horrible recoil and ejection at one o’clock.
It was over gassed before the can, even worse with it.

The GP5 is a good suppressor with reasonable back pressure, but the base port in the barrel was just too large.

Example image of GP5 suppressor for interest. Actual upper was a different brand.




After ordering up a dedicated suppressed EZTUNE, we received this feedback.

Dammit you guys nailed it, runs smooth and ejects at 3:30 constant with the can.
Let me tell you I was about to send this barrel back to Noveske and ask them why f#@k such a big gas port?
It was obnoxious to shoot, even with A5 H5 7.5 oz buffer weight and a blue spring and still kicked and was worse with the weight and spring.
Not to mention the gas all over you from so much being pushed back.
Accuracy is superb with my hand loads and now it’s a pleasure to handle.
I give my Thanks and appreciation

[Leonidas24]

Sometimes customer feedback just makes us smile.

David wanted to use a Griffin GP5 direct thread suppressor on his 10.5 upper, but was having issues.



The GP5 is a good suppressor with reasonable back pressure, but the base port in the barrel was just too large


After ordering up a dedicated suppressed EZTUNE, we received this feedback.

A couple points. First, Noveske barrels are obnoxiously overgassed. I bought a 12.5 Crusader stainless in 2009 that needed an H3 and increased power recoil spring just to run .223 reliably. Open source information on gas ports was almost non-existent or at the very least was not discussed in public forums with great detail. It was an incredibly accurate barrel when it wasn't failing to extract or nose diving rounds into the feedramps. This experience was the reason I don't recommend Noveske barrels without a Switchblock or reducing gas port insert/BRT tube.

Fast forward to today; I've had a Centurion 12.5 LW CHF for the past four years that's been excellent. Pin gauged at .066 new and ran like a top unsuppressed but gassed me out pretty hard with a SiCo Saker. A couple weeks ago I tried a .059 BRT tube to see what effect it had with the can on. Night and day comparison to the stock configuration but of course it wouldn't run w/o the can. I was able to trade the .059 tube for a .063 and restored unsuppressed function with 5.56 ammo, and have yet to try it with .223. It ejects around 2:30 suppressed, and while I primarily shoot it with the can, it's nice to have the ability to shoot w/o the Saker installed. BCG is a Centurion phosphate and the recoil system is an A5H2 and Sprinco green spring. The Saker has a Rearden Atlas installed, and the muzzle device is an FCD 6315RF.