After only a few short weeks my of waiting the MEGA ARMS MA-TEN 308 AR RECEIVER SET arrived exactly as scheduled. My first impressions out of the box is very good. The units have been manufactured and finished flawlessly. The MEGA ARMS MA-TEN 308 AR RECEIVER SET will be used in the #3 308 AR build project at 308AR.com.
Category: AR 308 Projects
This 308 AR rifle build is an intermediate stage of another project. The plan is to use a matching SI Defense Generation II Upper and Lower Receiver, but at this time the lower is not in my possession. So for curiosity sake I took the SI Defense Upper and installed it on my DPMS LR-308 Lower from my DPMS LR-308 Precision Rifle Project on this site.
The upper consists of the following hardware:
- SI DEFENSE GENERATION II STRIPPED UPPER RECEIVER
- DPMS 308-BL-SASS 18″ FLUTED BARREL and MATCHING SASS GAS BLOCK GB-SASS
- JP/VTAC JPHG-6D JP Modular Hand Guard, Extra Long 15.5
- DPMS 308-BCA Bolt Carrier Group
I recently came upon a good deal on a DPMS 7.62 SASS Teflon Coated, Fluted Barrel. The problem is I cant have a threaded muzzle in my home state so the threads needed to go.
Rather than send the barrel out to a gunsmith I decided to machine it myself in the lathe at my day job. It was pretty easy and I think it turned out well.
Here’s what I did.
- I wrapped the barrel with a precision shim stock perfectly for nearly 360 degrees. This was done to protect the teflon finish from the lathe jaws.
- Then I placed the barrel in a 4 jaw chuck. I used the 4 jaw because its the easiest way to get the bore centered.
- I indicated the bore and adjusted the chuck until the bore was rotating perfectly centered.
- Next step was to remove the threads from the muzzle
- After removing the threads I adjusted the tool holder to give me the 11 degree crown.
- Cut the crown to a mirror finish
I have read that a brass ball with lapping compound is typically used to fine hone where the crown meets the bore. I decided to skip this step for now just to see if it matters.