BRT EZTUNE Gas Tubes

[everready73]

.073 for a carbine gas 16''? That is pretty huge

What size did you end up ordering? I believe you order a size or 2 smaller than what you would want at the port due to the way gas drive works. I would think .060-.062 would be around where you want to be. Betting h2 or even h will run smooth.

Let us know how it works out. I love the inserts, might be ordering a tube for my uncle's gun

[B52U]

.073 for a carbine gas 16''? That is pretty huge

What size did you end up ordering? I believe you order a size or 2 smaller than what you would want at the port due to the way gas drive works. I would think .060-.062 would be around where you want to be. Betting h2 or even h will run smooth.

Let us know how it works out. I love the inserts, might be ordering a tube for my uncle's gun

It is a 14.7" with pinned A2 FH. BRT recommended the .0635 gas tube. On the tubes they indicate to go up one size from the targeted barrel port size for equivalent function. I'm pretty interested to see what buffer I can run with the springco blue I have currently. I have all the different weight combos I can try. Whatever nets the best ejection and consistent lockback.

[Clint]

Yes, this is actually fairly common.

Across dozens of barrel mfgs, gas port sizes average ~15% larger (by area) than needed.

.073 for a carbine gas 16''? That is pretty huge

What size did you end up ordering? I believe you order a size or 2 smaller than what you would want at the port due to the way gas drive works. I would think .060-.062 would be around where you want to be. Betting h2 or even h will run smooth.

Let us know how it works out. I love the inserts, might be ordering a tube for my uncle's gun

[georgeib]

Clint, I'm thinking of using your has tube for a my 18" midlength Blackhole Weaponry barrel 308. The port is .081 on a .750 gas block journal, and the barrel feels very over gassed. I've been using an SLR adjustable gas block almost all the way locked down to tame it.

What port size gas tube would you recommend, please?

[Clint]

We don't have quite as good data for 308 applications, but most info points towards very similar sizes to 223.

An 076 size would be a good starting point.

Clint, I'm thinking of using your has tube for a my 18" midlength Blackhole Weaponry barrel 308. The port is .081 on a .750 gas block journal, and the barrel feels very over gassed. I've been using an SLR adjustable gas block almost all the way locked down to tame it.

What port size gas tube would you recommend, please?

[Grip]

I'm thinking of using your gas tube for a my 13.7" midlength Noveske 5.56 barrel. The port is .086 on a .750 gas block journal, and the barrel is very over gassed. I've been using an SLR adjustable gas block almost all the way locked down to tame it. This Barrel is shooting suppressed 95% of the time.

What port size gas tube would you recommend, please?

[georgeib]

We don't have quite as good data for 308 applications, but most info points towards very similar sizes to 223.

An 076 size would be a good starting point.

Could I start smaller and then drill it larger if necessary like your gas block inserts?

[Diamondback]

Here's a slightly more exotic one... Could EZTune adjust a milspec 20" rifle's gas drive to reliably cycle with an H or H2 buffer rather than H3 or H6? Idea here is a build with M16 and M4 uppers sharing a common lower assembly, hoping to not have to remember to swap buffers as part of the switch.

[Clint]

Nah, that one's pretty easy and our general goal is to get all uppers gassed about the same.

For a rifle length, we'd have to modify a standard tube. Just order the midlength and add a note to make it rifle.

Here's a slightly more exotic one... Could EZTune adjust a milspec 20" rifle's gas drive to reliably cycle with an H or H2 buffer rather than H3 or H6? Idea here is a build with M16 and M4 uppers sharing a common lower assembly, hoping to not have to remember to swap buffers as part of the switch.

[GrumpyM4]

A barrel's throat will be gone WAY before any port erosion would be an issue. I'm really interested in these tubes though. I just haven't wrenched on any guns for a while..

What this guy said.

My question is what is the expected round count life of one of these gas tubes?

After seeing guns burn holes in the topside of the gas tube between 10k and 15k rounds with proper sized gas ports, how long will the thin wall of these gas tubes last?