In the following posts:
- AR-MPR: Accurizing the Upper Receiver – Part II: Milling and Receiver Face Truing
- AR-MPR: Accurizing the Upper Receiver – Part I: Prep and Welding
- AR-MPR: Accurizing the Upper Receiver – Overview
I’ve documented an experiment in accurizing the upper receiver of the AR-MPR rifle. It was a bit painful to file away hard anodizing, followed by drilling, welding, milling, and finally epoxy bedding. The whole point was to remove slop between the upper and lower receivers on the AR-MPR rifle.
I finally had a chance to test out the rifle with the modifications in place. I did a quick sight-in on the paper at 25 yards, then dialed it in at 100 yards. From a bipod and rigged up rear rest, the first 5-shot group measured just .604″ (.577 MOA) – well within the .5-.75 MOA goal for the project.
Next, I’m looking forward to shooting off a proper rest, and experimenting with different loads to see how good this rifle can get.
I’m confident that this rifle will continue to turn in more great groups. Stay tuned, because there’s another related project coming up!