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Sholo · Veteran Member

I've been wanting to make an RVA for my AR2078 for some time now, but, not having a lathe or milling machine, I was a little hesitant about how to go about it using a cheap Mastercraft drill press, Dremel, etc. I'm sure (?) I could have whittled something out - maybe - but I AM sure it would have been fairly crude with brutal tolerances!

So I contacted our very own SMP to see if he could possibly make me one, or at least give me some pointers on how to attack the project using my "caveman" tools. Man...am I ever glad I did! I was told to bring all my pieces down and he would whip me one up on the spot... Cool

Here is the finished product with the factory one above for comparison:

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I went with this style as I wanted both an RVA, but still have the gun retain its factory looks as much as possible. The new cocking block is .200" longer than stock to allow for a bit more adjustment range, and now sits right tight to the new end cap. Right behind the cocking pin, there is a hole drilled/tapped 8-32 where a nylon plug, the smallest spring I've ever seen, and an 8-32 set screw make up a "brake" to keep adjuster/spring guide from moving once set where I want it. The threaded end of spring guide was also drilled/tapped for an 8-32 set screw (with red Loctite applied), and spring tension is adjusted by inserting an allen key through a small hole drilled in end cap.

Seeing as the end cap now sits tight to cocking block, it was bored .312" x .450" deep to allow adjuster enough room to be backed off. There is a shoulder milled in cocking block to prevent it from backing completely out:

When all was said and done, I ended up with just over 1/2" of total adjustment range, which should be more than enough to tune the gun to whatever velocity I desire:

Thanks a million Sean! Not just for the RVA, but also for you and your wife (and MacKenzie) allowing me into your home, the great hospitality, patiently answering my numerous questions, and showing me the basics of working with a metal lathe/milling machine. I learned more in an afternoon watching you than I have in the last year reading "how-to" articles. It truly was a most enjoyable afternoon, for sure (for me, anyways!) Only downside is I now have to convince the wife that I NEED those same tools! Maybe I will have to get her that corner tub afterall... Wink

Cheers,
Todd