04-21-2018, 02:10 PM
I checked my brass, and sure enough, it's exactly like what has been mentioned above. The first 13 rounds were pretty bad. Deep scratches below the shoulder, and I was concerned. I was also having issues that remind me of an under gassed system, and quit when I had a rather pronounced bolt-over. I don't know how I missed the scratches?
I put the upper in my vise, turned where I could get a good look at the extension and chamber. I couldn't see anything in the chamber itself, but there was an apparent burr on one of the bottom extension lugs. On my attempt to get a pick in the extension and check if it was a piece of dirt, it was definitely a burr. When I pushed on it to see if I could knock it off, sure enough, it broke off and came out. Okay, back to the range.
Next 30 rounds all fed MUCH better, bolt locked back, and things seem to be overall more-bettah Gretta! (BTW, the LaRue Tranquillo brake makes a rather awesome fireball at dusk folks, really cool stuff) Still had scratches on the shoulders of all my brass though, my best guess is that the remaining, smaller burs on the extension are the culprit.
When I got home, I put the upper back in the vise, reviewed the chamber, and sure enough, the little burrs were still there. Nothing had apparently changed, so I whipped out the trusty Craftsman shaft driven dremel, chucked in a fine pointed stone and touched the interior of the extension teeth on the corners and knocked the burrs I could see down. Since I was already here, I went ahead and hit the teeth all the way across, all the way around. Better now than later, as I was already here. Then, I used a foam ear plug and some (1800? -label has been long missing) polishing rouge, moistened with some SeaFoam, and went into the chamber up to - but not beyond - the shoulder. I washed the barrel bore and chamber with copious amounts of SeaFoam, oiled her up, and am hoping to get back out to further test the results today.
It was late last night when I was finally putting things up, and I didn't get any pics of the extension after, but here are a few shots of the actual burrs I found and removed.
![[Image: 40701039575_6e3a32dba5_b.jpg]](https://farm1.staticflickr.com/903/40701039575_6e3a32dba5_b.jpg)
Extension burr by ., on Flickr
![[Image: 41560833242_60e5dd27c4_b.jpg]](https://farm1.staticflickr.com/796/41560833242_60e5dd27c4_b.jpg)
Untitled by ., on Flickr
My brass initially. This is after I had de-primed on a lee universal de-capping die, and a 1.5hr wet tumble.
![[Image: 40890226664_540bbce21d_b.jpg]](https://farm1.staticflickr.com/875/40890226664_540bbce21d_b.jpg)
Untitled by ., on Flickr
My brass last night. Much smaller scratches, but still present. I put 10 BLACK and 20 rounds of steel case, thinking that the steel cases could help do some work for me...
![[Image: 41560871362_26cef072e5_b.jpg]](https://farm1.staticflickr.com/896/41560871362_26cef072e5_b.jpg)
Untitled by ., on Flickr
I will report back this afternoon or evening after I get back out to re-fire the weapon to get a more definite diagnosis of my issues. I will be surprised of this doesn't fix it, and I'll be up and running. I know BFT is already on it.
P.S. Do you have any idea how hard it is to get a good pic of the extension with a flashlight and an Iphone? Fail-sauce, KS, just -fail.
I put the upper in my vise, turned where I could get a good look at the extension and chamber. I couldn't see anything in the chamber itself, but there was an apparent burr on one of the bottom extension lugs. On my attempt to get a pick in the extension and check if it was a piece of dirt, it was definitely a burr. When I pushed on it to see if I could knock it off, sure enough, it broke off and came out. Okay, back to the range.
Next 30 rounds all fed MUCH better, bolt locked back, and things seem to be overall more-bettah Gretta! (BTW, the LaRue Tranquillo brake makes a rather awesome fireball at dusk folks, really cool stuff) Still had scratches on the shoulders of all my brass though, my best guess is that the remaining, smaller burs on the extension are the culprit.
When I got home, I put the upper back in the vise, reviewed the chamber, and sure enough, the little burrs were still there. Nothing had apparently changed, so I whipped out the trusty Craftsman shaft driven dremel, chucked in a fine pointed stone and touched the interior of the extension teeth on the corners and knocked the burrs I could see down. Since I was already here, I went ahead and hit the teeth all the way across, all the way around. Better now than later, as I was already here. Then, I used a foam ear plug and some (1800? -label has been long missing) polishing rouge, moistened with some SeaFoam, and went into the chamber up to - but not beyond - the shoulder. I washed the barrel bore and chamber with copious amounts of SeaFoam, oiled her up, and am hoping to get back out to further test the results today.
It was late last night when I was finally putting things up, and I didn't get any pics of the extension after, but here are a few shots of the actual burrs I found and removed.
Extension burr by ., on FlickrUntitled by ., on FlickrMy brass initially. This is after I had de-primed on a lee universal de-capping die, and a 1.5hr wet tumble.
Untitled by ., on FlickrMy brass last night. Much smaller scratches, but still present. I put 10 BLACK and 20 rounds of steel case, thinking that the steel cases could help do some work for me...
Untitled by ., on FlickrI will report back this afternoon or evening after I get back out to re-fire the weapon to get a more definite diagnosis of my issues. I will be surprised of this doesn't fix it, and I'll be up and running. I know BFT is already on it.
P.S. Do you have any idea how hard it is to get a good pic of the extension with a flashlight and an Iphone? Fail-sauce, KS, just -fail.
Nothing kills the incentive of men faster than a healthy sense of entitlement. Nothing kills entitlement faster than a healthy sense of achievement.