05-08-2018, 08:00 PM
Hi guys, I have a Kies Custom .264 LBC upper with the stainless steel barrel. I've measured the bolt face depth at 0.125", and it does not close on a go gauge (either with the bolt in the bolt carrier, or with the bolt removed from the carrier). It also doesn't close on a no-go gauge. Maybe it could be forced closed on the go gauge but I figured that would damage the chamber or gauge.
I checked the headspace because it often fails to extract the case from the chamber--but the extractor grips the case firmly, the gas system just doesn't have enough "power" to get the case unstuck, and indeed it's very hard for me to work the charging handle to get a fired case out. Additionally, the fired brass often has a very faint groove that I can't really feel with my finger as it's not at all deep, but still attracts light. (This only with Hornady A-max or Wolf MTP brass, no steel-cased stuff). I've tried cleaning out the chamber with a brush to no avail (gauge still doesn't fit), and can't see any obvious obstructions. I have also played with the adjustable gas block although I understand that sometimes it gets clogged to the point that opening it fully still doesn't supply enough gas.
Do you guys think that I have the wrong bolt (that I should have a 0.136" bolt?)? Is it worth buying a 0.136" bolt to see if it closes on a go gauge? I couldn't see an obvious place on the upper that would say whether it's a Type I or Type II chamber, any idea where to look? (Do I have to take off the handguard and look at the bbl? I'm a bit of an AR noob and not sure if I should since it's a free-floated handguard). Or should I look for a pro who can re-ream the barrel? Any recommendations of guys who specialize in Grendel?
I checked the headspace because it often fails to extract the case from the chamber--but the extractor grips the case firmly, the gas system just doesn't have enough "power" to get the case unstuck, and indeed it's very hard for me to work the charging handle to get a fired case out. Additionally, the fired brass often has a very faint groove that I can't really feel with my finger as it's not at all deep, but still attracts light. (This only with Hornady A-max or Wolf MTP brass, no steel-cased stuff). I've tried cleaning out the chamber with a brush to no avail (gauge still doesn't fit), and can't see any obvious obstructions. I have also played with the adjustable gas block although I understand that sometimes it gets clogged to the point that opening it fully still doesn't supply enough gas.
Do you guys think that I have the wrong bolt (that I should have a 0.136" bolt?)? Is it worth buying a 0.136" bolt to see if it closes on a go gauge? I couldn't see an obvious place on the upper that would say whether it's a Type I or Type II chamber, any idea where to look? (Do I have to take off the handguard and look at the bbl? I'm a bit of an AR noob and not sure if I should since it's a free-floated handguard). Or should I look for a pro who can re-ream the barrel? Any recommendations of guys who specialize in Grendel?