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Welcome. If you want a .124" bolt face depth, with an extractor that will actually work, I would point you towards LMT's enhanced bolt.
The post-Colt industry attempts to make a reliable 7.62x39 bolt and extractor have been a continual failure, because they are using a bolt face depth that doesn't leave much room for the optimal extractor groove geometry when looking at articulation of the 7.62x39 case rim thickness in and out of the bolt face, and how the extractor snaps over the rim, then has a lot of axial load applied to it during the extraction cycle.
I was just measuring one the other day that had been used to build a 6mm Grendel, and I told my friend that it will most likely break, given that there was maybe .050" at the most of extractor lip thickness from inside the lip to the front of the extractor.
There are several areas on the half-cocked 7.62x39 bolts that present significant mechanical engineering challenges for designers, and most have been overlooked since Colt did it right back with the Colt 7.62x39 Sporter II.
This is why the .50 Beowulf and 6.5 Grendel use a .136" bolt face depth, with a well-designed and thoroughly tested bolt that actually lasts.
Are you needing this to replace a broken bolt, or for a new build?
NRA Basic, Pistol, Rifle, Shotgun, RSO
CCW, CQM, DM, Long Range Rifle Instructor
6.5 Grendel Reloading Handbooks & chamber brushes can be found here:
Not to hijack a thread but I have a type 2 bolt w/ an extractor that chews up Lapua brass case heads but does great w/Hornady. I can only assume the Lapua has a thicker lip on there brass. If I pick up an enhanced extractor from PF it should solve my issue right?
Not to hijack a thread but I have a type 2 bolt w/ an extractor that chews up Lapua brass case heads but does great w/Hornady. I can only assume the Lapua has a thicker lip on there brass. If I pick up an enhanced extractor from PF it should solve my issue right?
You probably have an ejector that needs to be radiused. If you take a Lapua case, and hold it next to a Hornady case, you'll see that the Hornady case head has a nice chamfer to it, which assists in feeding past the ejector in right hand lip presentation from the magazine.
Radiusing the ejector solves this problem. The Hornady brass, Lapua, and even the PPU all have a .055" rim thickness, but the Hornady has the best geometry with the chamfered edge of the rim for feeding.
Also remember that "Type I" and "Type II" are Black Hole Weaponry terms for their company internal purposes to ID what kind of chamber depth they have used when chambering .264 LBC barrels.
If you want a hand-fit bolt with custom shop features for improved handling of your brass, those need to be performed by a competent smith.
NRA Basic, Pistol, Rifle, Shotgun, RSO
CCW, CQM, DM, Long Range Rifle Instructor
6.5 Grendel Reloading Handbooks & chamber brushes can be found here:
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