Unreal.
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A Tale of Two Crush Washers, or Two Crush Washers One Barrel, and other AR oddities
- Thread starter cmshoot
- Start date
Hardened?
Probably hardened but not tempered after, so it's so hard it becomes brittle.
But as you said, they might have gotten the wrong alloy from a supplier, then heat treated it incorrectly, because it wasn't what they thought it was.
Quarters and the AR:
An easy, field expedient method to check and see if your BCG is traveling too far to the rear is to use 2 US quarters (the coins).
When fully to the rear, there should be a gap between the rear of the gas key vase and the extension on the lower receiver the thickness of 2 quarters.
So you check it, and you can only fit 1 quarter in between the two. Remove your buffer and buffer spring, drop a quarter into the bottom of your receiver extension (buffer tube), reassemble, and check it again.
Gas key impacting the back of the lower receiver? Drop 2 quarters in there.
Had a customer with a BCA build. Normally I would be disgusted, but this was a side-charging .22WMR, and I think that's sort of cool.
He was having to solve one problem after another with it. some of which I helped him with.
The BCG was traveling too far to the rear, allowing the charging handle to impact the back of the cutout that it travels in. After a few rounds, it was breaking the charging handle.
Upper went back and forth to BCA, continued to have the same issue. Customer brought it to me and explained the issue. I told him to drop a couple quarters in his receiver extension. Great success! Problem solved.
An easy, field expedient method to check and see if your BCG is traveling too far to the rear is to use 2 US quarters (the coins).
When fully to the rear, there should be a gap between the rear of the gas key vase and the extension on the lower receiver the thickness of 2 quarters.
So you check it, and you can only fit 1 quarter in between the two. Remove your buffer and buffer spring, drop a quarter into the bottom of your receiver extension (buffer tube), reassemble, and check it again.
Gas key impacting the back of the lower receiver? Drop 2 quarters in there.
Had a customer with a BCA build. Normally I would be disgusted, but this was a side-charging .22WMR, and I think that's sort of cool.
He was having to solve one problem after another with it. some of which I helped him with.
The BCG was traveling too far to the rear, allowing the charging handle to impact the back of the cutout that it travels in. After a few rounds, it was breaking the charging handle.
Upper went back and forth to BCA, continued to have the same issue. Customer brought it to me and explained the issue. I told him to drop a couple quarters in his receiver extension. Great success! Problem solved.
Customer came in for Armorer work. States he bought a "brand new" 16" Radical Firearms AR in .300Blk from a Cartersville-area dealer while at a recent RK Gun Show.
Took it to the range, couldn't get a round to fully chamber, so he never fired it. Brought it to me, where I found the neck of a casing stuck in the throat.
More than likely, someone fired a 5.56 in the .300Blk. So, either the gun was in fact new, and Radical Firearms did it during test fire, which would not surprise me...........or, it was a used rifle sold to him as new. I will say, there was more wear on the edges and corners of the charging handle than I've ever seen in a new AR.
The device used to keep tension on the A2-style flash hider was some weird hybrid of a shim and a crush washer. Never seen one before. I had to cut it off the barrel because it was severely deformed.
The hole in the gas block for the gas tube roll pin was oversized. You could just about drop a roll pin through it. Pretty good chance that under normal use, that pin would have fallen out, allowing the gas tube to move, which would stop the AR from functioning.
Additionally, whoever installed the gas block whanged the crap out of it at least 3 times with a hammer. This is cosmetic damage only, but who wants that on their brand new gun? I start my gas tube roll pins with a Geissele tool made for the task, then drive them home using a punch and a hammer. This way I'm guaranteed not to hit the gas block with my hammer. I replaced the factory gas block with a new one from Cross Machine Tool.
Long story short, we decided to rebarrel it in 5.56. First barrel I grabbed was a brand new Anderson 16" with a carbine length gas system. Checked the gas port before installation. Spec for a gas port for a 5.56, 14.5"-16" barrel, with a carbine-length gas system is .0625". The first Anderson barrel I grabbed had a .073" gas port. Second one I grabbed was .069".
That's when I found a barrel I forgot we had; a 16", midlength, 5.56 Bergara barrel, lightly used, and less than half the price of a new one. Gas port should have been .076" on that barrel, but I found it a little tight at .072". I reamed the port out to the proper .076" and installed the barrel. Barrel was already dimpled, and I verified that it was located properly.
Got everything assembled. During final inspection, I found that there wasn't quite as much contact between the face of the buffer and the tail of the bolt carrier. I explained it to the customer, and told him what to look for on the face of his buffer, in case it's contacting the buffer retainer under fire. I told him that if he saw such indicators, to bring it back to me.
Took it to the range, couldn't get a round to fully chamber, so he never fired it. Brought it to me, where I found the neck of a casing stuck in the throat.
More than likely, someone fired a 5.56 in the .300Blk. So, either the gun was in fact new, and Radical Firearms did it during test fire, which would not surprise me...........or, it was a used rifle sold to him as new. I will say, there was more wear on the edges and corners of the charging handle than I've ever seen in a new AR.
The device used to keep tension on the A2-style flash hider was some weird hybrid of a shim and a crush washer. Never seen one before. I had to cut it off the barrel because it was severely deformed.
The hole in the gas block for the gas tube roll pin was oversized. You could just about drop a roll pin through it. Pretty good chance that under normal use, that pin would have fallen out, allowing the gas tube to move, which would stop the AR from functioning.
Additionally, whoever installed the gas block whanged the crap out of it at least 3 times with a hammer. This is cosmetic damage only, but who wants that on their brand new gun? I start my gas tube roll pins with a Geissele tool made for the task, then drive them home using a punch and a hammer. This way I'm guaranteed not to hit the gas block with my hammer. I replaced the factory gas block with a new one from Cross Machine Tool.
Long story short, we decided to rebarrel it in 5.56. First barrel I grabbed was a brand new Anderson 16" with a carbine length gas system. Checked the gas port before installation. Spec for a gas port for a 5.56, 14.5"-16" barrel, with a carbine-length gas system is .0625". The first Anderson barrel I grabbed had a .073" gas port. Second one I grabbed was .069".
That's when I found a barrel I forgot we had; a 16", midlength, 5.56 Bergara barrel, lightly used, and less than half the price of a new one. Gas port should have been .076" on that barrel, but I found it a little tight at .072". I reamed the port out to the proper .076" and installed the barrel. Barrel was already dimpled, and I verified that it was located properly.
Got everything assembled. During final inspection, I found that there wasn't quite as much contact between the face of the buffer and the tail of the bolt carrier. I explained it to the customer, and told him what to look for on the face of his buffer, in case it's contacting the buffer retainer under fire. I told him that if he saw such indicators, to bring it back to me.
I consider this an oddity:
I walked in a store yesterday with a rifle and a bunch of parts. No appointment. Walked out an hour later with my rifle, a new friend and a much better understanding of the difference between someone who can build an AR (me) and someone who mastered the process (Shep).
Long story even longer... this place (ODT) continues to impress me. I’ve had dealings with some of the finest people I’ve ever met through ODT. Yesterday was no exception.
Thank you
cmshoot
and thank you Truprep!
I walked in a store yesterday with a rifle and a bunch of parts. No appointment. Walked out an hour later with my rifle, a new friend and a much better understanding of the difference between someone who can build an AR (me) and someone who mastered the process (Shep).
Long story even longer... this place (ODT) continues to impress me. I’ve had dealings with some of the finest people I’ve ever met through ODT. Yesterday was no exception.
Thank you
cmshoot
and thank you Truprep!
