So, I have been wanting an AR for quite some time. I own the popular hunting calibers, 30-30, 30-06 etc... But I wanted a sporting rifle.
I wanted to build it however (I did buy a complete upper), to learn more about the weapon and get some satisfaction from actually creating something.
First, I decided to machine my own lower. The lower I chose was a JMT composite lower. The price is a bit steep, but the jig is excellent, fast shipping, and great tech service (we discussed tooling).
I decided to use a trusty Harbor Freight drill press, with an X-Y vice, to do the machining. Great drill press, everything squared up easily, and we were off and running. I do have almost a decade of machining background, so the concepts here were understood, and I held all of the tolerances within .005" with a drill press. Basically it was roughed with a center cutting .375", 4 flute TiN coated end mill, plunge cutting. I left .015" on the bottom of the pockets, .0625" on the walls.
I then ran multiple finishing passes on the bottom to achieve the proper depth, removing .005" per pass. Then to the walls... I used a Sharpie to color the edges of the jig, like you would use dye while machining metal. I used this as a rough guide. Once I barely skimmed the edges of the jig, I used the actual rifle components, to match machine the pocket widths to the hammer, trigger, and rear takedown lug.
I used a PSA LPK with their enhanced trigger group, (polished, nickel plated). I also installed some SS CCT anti walk/rotation pins. The upper and lower fit VERY tight.
The upper is from Hardened Arms. It is a 1/7, 5.56 chambered, 16" SOCOM with their 10" SDX rail. I did opt for the NiB BCG and the Gunfighter CH. The delivery took 3.5 weeks, but I am very pleased with the build quality of the upper.
I found a great deal on a Bushnell red dot, and mounted that to a mid height riser, and co-witnessed that with a set of Cobratac BUIS. My first rear BUIS from them would not LOCK upright, it simply had a detent... They replaced it no questions asked, within a week. Great service.
Also installed a Gamma 556 compensator.
I've had it at the range a couple times, and I am very pleased. Everything operates flawlessly, and I had a great time building it. Looking forward to milling out a few more lowers, and completing a few more builds!
I wanted to build it however (I did buy a complete upper), to learn more about the weapon and get some satisfaction from actually creating something.
First, I decided to machine my own lower. The lower I chose was a JMT composite lower. The price is a bit steep, but the jig is excellent, fast shipping, and great tech service (we discussed tooling).
I decided to use a trusty Harbor Freight drill press, with an X-Y vice, to do the machining. Great drill press, everything squared up easily, and we were off and running. I do have almost a decade of machining background, so the concepts here were understood, and I held all of the tolerances within .005" with a drill press. Basically it was roughed with a center cutting .375", 4 flute TiN coated end mill, plunge cutting. I left .015" on the bottom of the pockets, .0625" on the walls.
I then ran multiple finishing passes on the bottom to achieve the proper depth, removing .005" per pass. Then to the walls... I used a Sharpie to color the edges of the jig, like you would use dye while machining metal. I used this as a rough guide. Once I barely skimmed the edges of the jig, I used the actual rifle components, to match machine the pocket widths to the hammer, trigger, and rear takedown lug.
I used a PSA LPK with their enhanced trigger group, (polished, nickel plated). I also installed some SS CCT anti walk/rotation pins. The upper and lower fit VERY tight.
The upper is from Hardened Arms. It is a 1/7, 5.56 chambered, 16" SOCOM with their 10" SDX rail. I did opt for the NiB BCG and the Gunfighter CH. The delivery took 3.5 weeks, but I am very pleased with the build quality of the upper.
I found a great deal on a Bushnell red dot, and mounted that to a mid height riser, and co-witnessed that with a set of Cobratac BUIS. My first rear BUIS from them would not LOCK upright, it simply had a detent... They replaced it no questions asked, within a week. Great service.
Also installed a Gamma 556 compensator.
I've had it at the range a couple times, and I am very pleased. Everything operates flawlessly, and I had a great time building it. Looking forward to milling out a few more lowers, and completing a few more builds!
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LOL!
