I will be the first to admit this did not go as planned. I received the barrel pin from CNC Warrior . I had also ordered the drill bit and reamer from Shars . My plan was to drill then ream the hole .001 under the pin diameter and then tap the pin in place.
I wasn’t sure what to expect when drilling the hole. Since the hole is drilled through the receiver, and the barrel, I didn’t know if the drilling was going to be easy going through the receiver and then hard when it hit the barrel steel. Honestly it turned out to be no big deal. The steel drilled easily. Once through the near side of the receiver the drill bit slipped through with little resistance to the other side. The barrel had already been drilled when it was assembled in the old receiver, I suspect that remaining notch was already lined up.
The pin is suppose to be a press fit, but the hole drilled was too big despite the drill bit being .002 undersized.
The pin isn’t defective, the hole was drilled too large. I took a moment to try and figure out what to do. Obviously I couldn’t just order another pin. I can’t shrink the hole any. I ended up deciding to make my own pin.
From drilling out the old pin, I knew the steel was pretty soft, so I wasn’t concerned with finding a hardened steel pin. The barrel is pressed in, and the primary force that holds that barrel in place is the friction between the barrel and the receiver. I do not believe there is a significant amount of force being transmitted to the pin. It is there to prevent the barrel from working out after repeated firings.
I left the pin large. It was about 0.010 over the diameter of the original pin. I didn’t know if this was too big or not as I didn’t have a good means to measure the hole. It seemed like it started into the hole, so I figured that was good enough. Turns out, it was. I was able to drive in the pin with a hammer.
The last step is to put the handguard on and drive in the retaining roll pin.
At this point the rifle is completely assembled and ready for test firing. Like I said, this last part of the assembly did not go as planned. If I were to do it again, I would have used a drill bit that was under by .010 and then reamed to .001 under. This is the approach I would recommended for someone trying to follow in my footsteps. It still baffles me as to why the drill cut so oversized. I guess the good news is I have a brand new 0.1360″ reamer…I’ll need to find a project to us that on.