grayfox Wrote:Bj don't know about OP but it sounds a little risky to me. Would that take away the hardness layer? Don't know. If he was to do that, might be better to start with more like 1000 or even 1500, I found some at Home depot over in the paint section. How to do, stick a circle onto the end of the dowel w/ dbl-sided tape (ejector and extractor removed) and swish it by hand against the face? be sure to rinse out any grit afterwards...

204 AR Wrote:So was the upper completely built by Kies? If so I would have to think they used the correct bolt.

I've never used a headspace gauge, but is it necessary to remove the ejector and extractor first?

And if I understand correctly, it will chamber a factory round? It's just difficult to extract when fired or is it difficult to extract unfired also?

A close examination of the chamber is what I'd recommend, and polishing it if necessary.

Deplorable Wrote:Thanks guys. VASCAR2, yeah, Kies is out of business now...but used to use JoeBob as their distributor.

Grayfox, so would a 0.136" bolt work in a .264LBC chamber? (As long as the headspace is checked to be good with said 0.136" bolt?) And do you think there is any chance that it would have excessive headspace, even if the 0.125" has too little headspace? It's just so strange to me that a gun manufacturer could get something as basic as the headspace wrong.

Deplorable Wrote:Hi 204, it chambers a factory round just fine and easily extracts it by hand as long as it has not been fired. It's only after it fires that the brass sticks hard in the chamber.

Also, good question on the part about removing extractor/ejector. I didn't think about that, and certainly the ejector wanted to kick the gauge out of the bolt and may have made it a bit harder to twist the bolt (when removed from the bolt carrier) to lock. But it wouldn't lock on the Go gauge when it was in the BCG either, so I don't know. If anyone who knows for sure if I should have removed the ejector wants to chime in, that'd be great...

Klem Wrote:Yes, you can use headspace gauges on a fully assembled bolt with ejector. Assemble the BCG and rifle, load the gauge by hand, close the charge lever first and then use the base of your palm to press the back of the BCG into battery.
[ATTACH=CONFIG]11908[/ATTACH]

If the bolt is a .136" you need to source a finishing hand-reamer or ask a gunsmith to extend that chamber a tiny bit until the GO gauge closes. It sounds like it is almost there.

LRRPF52 Wrote:Les Baer (the company) has always used real Grendel bolts with .136" face depth. Some other companies that didn't do the engineering analysis of what it takes to make a reliable extractor used bolts with shallow face depth and figured it was the easiest, cheapest way for them to get into 6.5 Grendel or a variant of it.

The type of chamber variant does not determine the bolt face depth. You can chamber 6.5 Grendel SAAMI and .264 LBC-AR to whatever bolt you want. It's just that the thicker extractor claw on a .136" face depth bolt has more material to prevent shearing off than a .125" face depth bolt can ever have.

As to the OP's issue, I would find out what bolt the chamber was cut for first.

Deplorable Wrote:Great info, thanks Klem. In this case, the bolt is a 0.125". Do you think a finishing hand reamer would still be applicable? Or would a 0.136" bolt be more likely to work? (I'm worried about misfires if the gun really needs a 0.125", as another commentator pointed out. But if it in fact needs a 0.136" then that shouldn't be a problem)

Deplorable Wrote:Gotcha. So a .264LBC could take 0.125" or 0.136". Any idea how to find out? I looked on the upper and couldn't see any "Type I" vs "Type II" designation, which I think is what to look for. Also didn't see anything on the barrel but admittedly haven't taken off the freefloating handguard.