Colt Barrel Crane Chop Port Size Question

[Dutch110]

I have done the research on this and from what I can tell from posts on here from folks who have gone hands on with pin gauges, the port size for both the SOCOM and Govt profile Colt 14.5's is in the neighborhood of .063 (.0625 for some.) Also referenced the port size artifact that was linked to in another thread here for confirmation.

So I bought this barrel. Which is awesome. I love it. Its accurate. All the good things you can say about a Colt barrel. Now note, this is a Crane chop to 10.3 from a 14.5 barrel. But the port size is listed as .070. Side note I did email them to clarify.

https://www.littlebyrdprocurement.co...ofile-with-fsp

My assumption is that given this started life as a 14.5 that the true port size is actually the .063. Or does Crane drill out the gas ports when they shorten the barrels to match the 10.3 TDP which is .070? I have been considering putting a BRT tube on this (running with a can most of the time) and honestly do not have the pins (or desire to punch out the FSP) to gauge it myself. Hoping the collective has the required knowledge here.

[Clint]

It's pretty much standard practice to open the port as part of the chop process.

This should be expected anytime you buy a pre-chopped barrel.

Back in the old days, about the only way to get a dedicated suppressor barrel was to take a full length barrel and have it chopped and the gas port left alone.

These days, there are several companies that offer small ports and there is always the proven EZTUNE solution.

Also, if the linked barrel runs unsuppressed, the port has been opened up.

[Dutch110]

It's pretty much standard practice to open the port as part of the chop process.

This should be expected anytime you buy a pre-chopped barrel.

Back in the old days, about the only way to get a dedicated suppressor barrel was to take a full length barrel and have it chopped and the gas port left alone.

These days, there are several companies that offer small ports and there is always the proven EZTUNE solution.

Also, if the linked barrel runs unsuppressed, the port has been opened up.

Thanks Clint. The only reason I questioned it was I have a an 11.5 G barrel SBR with a .070 and same buffer/spring set up that feels like its running mo' gassy with the same can. More dwell time will do that I guess. Just gave me reason to pause. And yes, it runs fine without the can on it. What do you choke a setup like this down to assuming 50/50 use? OCL Polo K, A5H2 with Sprinco green? I am going to order a BRT tube for both of them but am just curious.

[Todd.K]

I wouldn’t really go smaller if your 50% unsuppressed needs to be 100% reliable.

If it’s just to get range time without heating up the suppressor then there is room to go down a bit.

Honestly though, I’d start with a dedicated suppressed setup. It’s going to give you a significant improvement on recoil and gas blowback. Then you know what you are giving up to make it run without the suppressor.

Or if I needed 100% reliable unsuppressed I would consider a flow through suppressor and live with it being a bit louder.

[Dutch110]

I wouldn’t really go smaller if your 50% unsuppressed needs to be 100% reliable.

If it’s just to get range time without heating up the suppressor then there is room to go down a bit.

Honestly though, I’d start with a dedicated suppressed setup. It’s going to give you a significant improvement on recoil and gas blowback. Then you know what you are giving up to make it run without the suppressor.

Or if I needed 100% reliable unsuppressed I would consider a flow through suppressor and live with it being a bit louder.

Flow through is not in the picture right now. Running only suppressed is not in my use case either. Both the 11.5 and 10.3 run fine now both with and without a can. This was only about reducing gas to the face. If that is not achievable then I am fine with them staying as they are right now. They aren't horrible in that regard when running the OCL Polo K. Charging handle and correct spring and buffer help in that regard. Just looking for a smidge more reduction. If not then so be it.