Advice on proof research barrel

[Anthony_Va]

I have recently built my first ar10 in 6.5cm. Used all quality parts like aero upper/lower, jp fmos bcc, proof research carbon 24"barrel.
The problem I'm having is for one, it will chamber a no go gauge, albeit barely. And it won't chamber it with one piece of scotch tape on the back of it.
The bigger problem with it seems to be throat length being really short. I loaded some 140gr sierra match king at the coal of 2.810" as listed on the load data from sierra. They would not come code to chambering in the rifle. I had to seat them all the way down to 2.755" before they would barely clear the lands. At that length they were only clearing by .005". I've been back and forth with them in a few emails but I haven't gotten anywhere yet. Going to call tomorrow.
I guess my question is, should I be upset with this barrel? Just looking for some opinions. I've got nearly 5500 bucks tied up in this rifle/scope combo. Not looking to deal with a sub par barrel in a rifle I plan to shoot out to 1k yds. Thanks everyone.

 

[Anthony_Va]

I'm just going to send it to them to lengthen the throat some.

 

[Evintos]

I wouldn't worry about it chambering the No Go Gauge. From a safety perspective, a Field Gauge is the one to use to determine safety.

Good call on sending it back. You wouldn't have been happy with it even if people told you not to.

Side note - From a gauge perspective, it's better to have a Go gauge and Field gauge (if a person doesn't want to buy the whole set) and do the Scotch tape trick on a Go Gauge as a makeshift No-Go Gauge.

 

[Anthony_Va]

I wouldn't worry about it chambering the No Go Gauge. From a safety perspective, a Field Gauge is the one to use to determine safety.

Good call on sending it back. You wouldn't have been happy with it even if people told you not to.
Aa
Side note - From a gauge perspective, it's better to have a Go gauge and Field gauge (if a person doesn't want to buy the whole set) and do the Scotch tape trick on a Go Gauge as a makeshift No-Go Gauge.

Yea the no go barely did chamber. It wouldn't with I piece of scotch tape though.
The throat was my real worry. I just couldn't stomach having to seat those bullets that deep. They told new to send it in and they would throat it.
Looking with a flash light, I can't even see a throat. It just looks like it goes straight from shoulder to lands lol.
Going to get a better look once I get the barrel removed

 

[CK1.0]

I don't know why you're using scotch tape on the back of a no-go gauge...

This is how to check headspace wth an AR:

 

[Anthony_Va]

I don't know why you're using scotch tape on the back of a no-go gauge...

This is how to check headspace wth an AR:

It was actually the advice of the guy at proof. I didn't think our made sense either. I guess it was their way of saying that it was okay for a nogo gauge to chamber. I was under the impression that a new barrel shouldn't chamber at all

 

[Evintos]

Basically the scotch tape adds just enough length (0.002") to a no-go gauge but the resulting combo still ends up being shorter than a field gauge. So if it doesn't chamber a no-go gauge with scotch tape, it definitely will not chamber a field gauge; aka it's safe.

The issue that could've arose is that it chambers a no-go gauge with the tape, then at that point, you'll definitely want to check with a field gauge.

A no-go gauge is some number in between GO (minimum standard headspace gauge) and Field (maximum standard headspace gauge) and it can be completely arbitrary with no set standard.

 

[CK1.0]

I'm curious what Proof says, maybe they're doing it like that (short throat) on purpose or something?

 

[SD Carpenter]

I just had problems with my new ar10 6.5 proof barrel, I'm still waiting on proof's engineer to get back from vacation on Thanksgiving. Last barrel I ever buy from these guys.

 

[Anthony_Va]

I just had problems with my new ar10 6.5 proof barrel, I'm still waiting on proof's engineer to get back from vacation on Thanksgiving. Last barrel I ever buy from these guys.

I hear you brother. They kinda talk to you like your stupid lol. they asked me like 3 times what bullet I was loading and tutored me on saami specs lol. My freebore is about .06 from where it needs to be just to fit the round. So ideally I would think it needs to be throated to about.08 from where it is now.