Loaded my first set of grendels.

[LRRPF52]

Go with an adjustable gas block if you want to push these types of loads. You can tame your rifle quite easily. Also, what buffer are you using? If you have dimpled primers with no cratering, I wouldn't worry about the ejector swipes, as long as they are more like a shadow than a cylindrical nipple.

[r3dn3ck]

Looks like garand syndrome isn't limited to garands. Bloody gas systems. Sounds like the adjustable gas block is probably the best option. I'd like to be able to make it a single shot like I can with my garand (adjustable gas plug). I'm using a standard 5.56 buffer but with the swiping I'm thinking it's the unlock that I need to slow down more than the BCG rearward velocity. Who makes the best adjustable gas block. I'm seeing a bunch of them with set screws to fix them to the barrel. I'd prefer a clamp type.

EDIT: on second thought the heavier buffer is contraindicated by the adjustable gas block.

[smoke13]

FYI. The neato scratch on your bullet is from extracting an unfired found. When the extractor pulls the bullet out and to the side the bullet is scratch on the feed ramp. This isn't anything to worry about b/c normally you are going to extract a spent brass without the bullet.

[RangerRick]

Go with an adjustable gas block if you want to push these types of loads. You can tame your rifle quite easily. Also, what buffer are you using? If you have dimpled primers with no cratering, I wouldn't worry about the ejector swipes, as long as they are more like a shadow than a cylindrical nipple.

+1 on this. Alot of Grendels seem to be over gassed.

RR

[LRRPF52]

Who makes the best adjustable gas block. I'm seeing a bunch of them with set screws to fix them to the barrel. I'd prefer a clamp type.

EDIT: on second thought the heavier buffer is contraindicated by the adjustable gas block.

JP makes several steel clamp-on adjustable gas blocks. You can still use a heavy buffer, you just delay the unlocking, as desired. Once the gas impulse gets the BCG moving, it will be going fast enough after you tune the system starting with under-gas and single round mags to test for bolt catch activation.

[LRRPF52]

http://www.jprifles.com/1.4.6_gs.php

[r3dn3ck]

I figured out my little shiny ring and burr on the case-heads issue. There's 2 bits happening. It's happening even with my lightest loads and doesn't seem to care about powder charge so far as far as intensity of the effect on the issue.

1, it looks like the bolt was originally cut for a .223 case head perhaps and converted to a .220 russian case head (6.5 grendel) or, the initial machining sucks a bit. in any case there's a rim about .001" tall making up the difference. I don't know if that's there on purpose for headspace but it's a junk method of doing headspace.

2, the bit of the extractor that sits in the extractor groove just under the case rim is about .0005 below the level of the bolt face allowing the brass to shave the tiniest of burrs up on the case head.

I'm considering a call to AA to query about this, ie.. is it normal expected status for one of their bolts? If not, do they have any interest in fixing it. I also figure that a AA employee of one sort or another browses this forum and might just see this.

AA, Alexander Arms, bolt face