I've only broken 5.56 bolts in guns I ran no less than 300rds through in each range session. Cracked at the cam pin hole after 10,000rds.
That was 16" CLGS with standard carbine buffer and spring. Dropped in a new bolt and kept going.
18" MLGS with large ports are really hard on bolts.
18" MLGS suppressed is really hard on bolts.
My 12" Grendel is 12" CLGS with a .068" port, run suppressed with Bootleg carrier set to fully suppressed position.
I currently have a standard carbine buffer in it, but will try it with the MGI RRB and Franklin Armory buffer with heavier spring.
The torsion from early unlocking will wear the bolt lugs and cause surface fractures at the lug roots, especially on the lugs adjacent to the extractor pocket.
Early unlocking is a gas system/recoil system timing issue common to guns that haven't been dialed-in.
Of all the Grendels I've owned and shot since 2009, in regular multi-day courses and events, I have yet to see any failures across multiple rifles. My build approach is more extensive than most manufacturers I know of though, and I'm pretty peculiar about what parts I allow near me.
That was 16" CLGS with standard carbine buffer and spring. Dropped in a new bolt and kept going.
18" MLGS with large ports are really hard on bolts.
18" MLGS suppressed is really hard on bolts.
My 12" Grendel is 12" CLGS with a .068" port, run suppressed with Bootleg carrier set to fully suppressed position.
I currently have a standard carbine buffer in it, but will try it with the MGI RRB and Franklin Armory buffer with heavier spring.
The torsion from early unlocking will wear the bolt lugs and cause surface fractures at the lug roots, especially on the lugs adjacent to the extractor pocket.
Early unlocking is a gas system/recoil system timing issue common to guns that haven't been dialed-in.
Of all the Grendels I've owned and shot since 2009, in regular multi-day courses and events, I have yet to see any failures across multiple rifles. My build approach is more extensive than most manufacturers I know of though, and I'm pretty peculiar about what parts I allow near me.
NRA Basic, Pistol, Rifle, Shotgun, RSO
CCW, CQM, DM, Long Range Rifle Instructor
6.5 Grendel Reloading Handbooks & chamber brushes can be found here:
www.AR15buildbox.com
CCW, CQM, DM, Long Range Rifle Instructor
6.5 Grendel Reloading Handbooks & chamber brushes can be found here:
www.AR15buildbox.com