Last night I tackled an issue that had been bugging me for a while. I had a lower receiver that had a CMMG ambi-safety on it that was hitting my trigger finger when I swiped it and it no longer needed it anyway. The problem is that the screw head holding the right side lever on was stripped out and no combination of slightly larger hex head bits was working. A Broken screw extractor didn't work either so it was on to Plan B.
1. Drilled through the head using a 7/64th bit, I didn't measure the depth but it was maybe 1/8" possibly a tad more. I was winging it.
2. Figuring I was dripping into the threaded shank I started applying gentle outward pressure with a flat head screw driver until I was able to break the bolt off at the head and remove the lever. This didn't take much effort, hindsight being 20/20 I should've padded the lower. The remaining part of the shank was exposed in the main safety lever as just a small nubbin.
3. To get what was left of the nubbin I used my Dremel and a diamond coated cutting wheel. It was the thinnest disk I had that could cut a slut in the top of the nubbin. I was careful to hold my hand steady so I didn't mangle the piece or go too deep and mar the safety lever.
4. After making the slot, the nubbin came out surprisingly easy with a well fitting flat head bit.
After I took the nubbin out I had no idea what size or thread pitch was but the Hillman thread gauge and a pair of calipers helped me narrow it down to a #4 bolt.
Luckily I had some 4-40 screws, albeit zinc coated, that I could use to confirm the thread pitch and it was a match. Today I went to the hardware store and picked up some 4-40 X 3/8" flat head bolts to make this ambi-safety whole again for the next project.
That's the nubbin all the way on the right that I removed.
No fancy tools, just a drill, a screw driver, and a dremel...a bubbagunsmith will survive. I've read of other people having similar issues so I thought I'd share my struggle and triumph from yesterday.
1. Drilled through the head using a 7/64th bit, I didn't measure the depth but it was maybe 1/8" possibly a tad more. I was winging it.
2. Figuring I was dripping into the threaded shank I started applying gentle outward pressure with a flat head screw driver until I was able to break the bolt off at the head and remove the lever. This didn't take much effort, hindsight being 20/20 I should've padded the lower. The remaining part of the shank was exposed in the main safety lever as just a small nubbin.
3. To get what was left of the nubbin I used my Dremel and a diamond coated cutting wheel. It was the thinnest disk I had that could cut a slut in the top of the nubbin. I was careful to hold my hand steady so I didn't mangle the piece or go too deep and mar the safety lever.
4. After making the slot, the nubbin came out surprisingly easy with a well fitting flat head bit.
After I took the nubbin out I had no idea what size or thread pitch was but the Hillman thread gauge and a pair of calipers helped me narrow it down to a #4 bolt.
Luckily I had some 4-40 screws, albeit zinc coated, that I could use to confirm the thread pitch and it was a match. Today I went to the hardware store and picked up some 4-40 X 3/8" flat head bolts to make this ambi-safety whole again for the next project.
That's the nubbin all the way on the right that I removed.
No fancy tools, just a drill, a screw driver, and a dremel...a bubbagunsmith will survive. I've read of other people having similar issues so I thought I'd share my struggle and triumph from yesterday.
