BSA1
member
Things I learned when building this AR or What YouTube videos do not cover.
Over the Christmas and New Years holiday season the bad weather and events cause me to retreat into the mancave. In doing so I finally managed to complete two AR projects. This particular AR turned out to be very challenging, informative and rewarding experience.
Now for the details;
For the Lower Assembly I used a Anderson closed trigger guard lower. I installed a heavy duty carbine buffer tube (7075 Aluminum), Mission First Tactical Minimalist Stock, Mission First Tactical grip, ALG ACT trigger and hammer and a lightweight bolt catch. I choose the MFT Stock and Grip to save weight. Assembly was straightforward and I had no problems.
For the BCG I choose a AERO Precision Black Nitride. Well made and high quality. No complaints.
So far so good but the Upper turned out to be a big challenge.
For the Upper I choose a Anderson smooth side Upper for a couple reasons. The first one is I believe the Forward Assist and Ejection Port Cover are unnecessary and the second reason was to save weight. I installed the barrel to the Upper and when I tried to attach it to the Lower it didn’t fit. The Pivot Pin fit fine but the Takedown Pin would only push partway in and I had to use a rubber tip hammer to drive it all of the way through the opposite side of the Lower. Ok I will reverse the assembly order by attaching it with the Takedown Pin first. No problem with the Takedown Pin but now the Pivot Pin would only push partway in so I had to reach for my trusty rubber tip hammer to drive it all the way home.
Hummm, not good at all. Fortunately I had another Anderson smooth side lower which fits the Pivot and Takedown Pins perfectly.
*builders note; check fit of Upper and Lower Receivers before starting assembly.
With that problem solved I moved on to the barrel. Since I was using a 15”
Free Float handguard I installed a CMMG gas tube. It took a lot of gentle tapping with a brass punch and my trusty rubber tip hammer to get it on. The good news is that sucker ain’t ever going to move. The set screws are just for looks.
With the Upper Receiver and Gas Block taken care of all that was left as to attach the barrel to the Lower. Or rather I tried to. I was using a 15” Free Float handguard with a rail that required the barrel nut be perfectly aligned with the Lower.
No go. Fortunately Brownells carries a barrel shim kit that has three different sizes of shims. With the shim kit on hand all I had to do was to mix and match the different sizes to get the barrel nut properly aligned.
Except how to get the shims on the barrel with removing the barrel nut and gas block. Remember how I said that the gas block ain’t going to move? After some long thinking it occurred to me that I could cut the shims and slip them onto the barrel behind the barrel nut. Aha! A pair of snips and a little mixing and matching of shims resulted in a perfect fit.
*builders note; do not install the gas block until after the barrel and barrel nut are checked for proper fit on the Lower.
With that problem solved all that was left was attaching the Free Float handguard and a A2 Flash Hider. For sights I am using SIG Romeo5 Red Dot.
The only remaining bad news is we have received a lot of rain, ice and snow and the range is too muddy to do any shooting. However the gun passed a function test in my back yard killing waterfilled Zombie water jugs.
I want to give a big shout-out to @GunnyUSMC for his help. I learned a lot and am very happy with the final result.
Now for some pictures;
Over the Christmas and New Years holiday season the bad weather and events cause me to retreat into the mancave. In doing so I finally managed to complete two AR projects. This particular AR turned out to be very challenging, informative and rewarding experience.
Now for the details;
For the Lower Assembly I used a Anderson closed trigger guard lower. I installed a heavy duty carbine buffer tube (7075 Aluminum), Mission First Tactical Minimalist Stock, Mission First Tactical grip, ALG ACT trigger and hammer and a lightweight bolt catch. I choose the MFT Stock and Grip to save weight. Assembly was straightforward and I had no problems.
For the BCG I choose a AERO Precision Black Nitride. Well made and high quality. No complaints.
So far so good but the Upper turned out to be a big challenge.
For the Upper I choose a Anderson smooth side Upper for a couple reasons. The first one is I believe the Forward Assist and Ejection Port Cover are unnecessary and the second reason was to save weight. I installed the barrel to the Upper and when I tried to attach it to the Lower it didn’t fit. The Pivot Pin fit fine but the Takedown Pin would only push partway in and I had to use a rubber tip hammer to drive it all of the way through the opposite side of the Lower. Ok I will reverse the assembly order by attaching it with the Takedown Pin first. No problem with the Takedown Pin but now the Pivot Pin would only push partway in so I had to reach for my trusty rubber tip hammer to drive it all the way home.
Hummm, not good at all. Fortunately I had another Anderson smooth side lower which fits the Pivot and Takedown Pins perfectly.
*builders note; check fit of Upper and Lower Receivers before starting assembly.
With that problem solved I moved on to the barrel. Since I was using a 15”
Free Float handguard I installed a CMMG gas tube. It took a lot of gentle tapping with a brass punch and my trusty rubber tip hammer to get it on. The good news is that sucker ain’t ever going to move. The set screws are just for looks.
With the Upper Receiver and Gas Block taken care of all that was left as to attach the barrel to the Lower. Or rather I tried to. I was using a 15” Free Float handguard with a rail that required the barrel nut be perfectly aligned with the Lower.
No go. Fortunately Brownells carries a barrel shim kit that has three different sizes of shims. With the shim kit on hand all I had to do was to mix and match the different sizes to get the barrel nut properly aligned.
Except how to get the shims on the barrel with removing the barrel nut and gas block. Remember how I said that the gas block ain’t going to move? After some long thinking it occurred to me that I could cut the shims and slip them onto the barrel behind the barrel nut. Aha! A pair of snips and a little mixing and matching of shims resulted in a perfect fit.
*builders note; do not install the gas block until after the barrel and barrel nut are checked for proper fit on the Lower.
With that problem solved all that was left was attaching the Free Float handguard and a A2 Flash Hider. For sights I am using SIG Romeo5 Red Dot.
The only remaining bad news is we have received a lot of rain, ice and snow and the range is too muddy to do any shooting. However the gun passed a function test in my back yard killing waterfilled Zombie water jugs.
I want to give a big shout-out to @GunnyUSMC for his help. I learned a lot and am very happy with the final result.
Now for some pictures;
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