Building an AR15 is fun. The old stoner design is easily worked on, and not much is needed to do the job. Parts swap is little harder than putting together a Mr. Potato Head toy. Even *I* can do this... and that means almost anyone can. Still, the AR design does hide a few $%#@!^& surprises for the neophyte, and has been known to have an old fart like me say some unkind things as well. Chief among those for the Old Fat Man... the blasted spring underneath the buttstock plate. The first time I ever removed an AR buttstock... well.... lets just say this ancient house has a LOT of hardware hidden in the cracks of the wood flooring, and there is a tiny bleeping spring down there keeping it all company.
The spring is there to push on a detent for an action pin. Not a complicated or precise job, it just serves to put pressure on the pin so it won't fall out on it's own. It's housed in an equally tiny hole drilled through the lower receiver, and the buttstock plate holds the spring in place once it's assembled. In other words, every time one takes off the buttstock, there is a miniature little partially invisible component that's under pressure there, just waiting to zing off into parts unknown and bring forth an exceptionally unfriendly verbal barrage from the would-be stock swapper.
Trying to outsmart the design, I decided to deal with it before I even began putting the guts in this Rock River lower. It's a hole, with a spring in it, and it's not rocket surgery. It just needs something to keep it there. Enter: a 4x40x1/8" set screw.... and a little 4x40 NC tap to make it fit. This tap is a perfect fit for the hole. So much so, that I ran the tap into the hole using nothing more than the multi-tool from my belt to grip it. In fact, I did it in my lap, while also chatting on the confuser, and had the plug installed in less than 5 minutes. The tap cut cleanly even while dry, almost scarily easy.
The tap and drill set, along with the vanishingly tiny plugs, came from Amazon. With less than $15 expended, I have the tools and parts to do the trick on this and the next three rifles I build.
I'm hoping the rest of the build goes this sweet!
(Now.... can someone point to where I might buy an A2 or A3 complete upper that doesn't cost more than just buying a whole new rifle?)