I went through what you're doing some time back, and I agree mostly with what's being said above. In my instance, it was an educational exercise, done so I could get a firmer grasp on what goes into an AR; and a largely successful effort to figure out where the money should be spent, and where the money should be saved. I got very lucky, and matters panned out favorably. They could just as easily gone the other way; luck was a critical factor, and that's no way to build guns.
From the start, I decided that the main money should go into the barrel.
I already had a rather spendy Stag Model 6 Super Varminter, which was built around a stainless 24" Bull barrel. The rifle came with a 1/2MOA accuracy guarantee, I was able to make it shoot to that standard with Prvi-Partizan 75gr Match several times, and I'm not a super great shooter by any means.
So I decided to go with a Stag 16" Model 3 barrel, and it was a good choice when the time came to find out what the gun would actually do. It shot to well under 1MOA, and for a first effort, I was positively thrilled. Every other part of that Upper was spec'd out based on lowest possible cost, and except for the barrel, all the parts came from Amazon.
After some commentary here, I began to realize that much of my good fortune was just pure luck, that I had gotten most of that luck by sticking very closely to the original Stoner design specs, and staying with a basic concept that very closely resembled a 16" USGI M-16. Where I would have gone loosie-goosie would have been in trying to get fancy. That's probably where I would have started having issues with gas length, buffer weights, and other cycling issues.
So I made a very basic decision about building ARs and AR Uppers right then and there; I was going to buy instead of build. The reasoning was/is that while these rifles actually
are Adult Legos, they still need more thought and planning/development than one might achieve by just slapping diverse parts together. Getting it right does not work infallibly just off the bat; it takes some experience involving getting some stuff wrong, and that requires a time and cash investment that I would not be able to sustain. So I decided that paying a bit extra to buy a complete setup from an established builder was well worth the premium.
But there are also reasonable limits, and the fact appears to me that a lot of folks are buying rifles with features they don't really need, often are not capable of taking full advantage of, and many of the builders are very happy to support their expanded egos without any comment.
Getting back to the Stag Model 6, it is a very nicely configured specialty rifle with an absolute minimum of costly features. Price wise it was (it's no longer offered) a deal at just under $1k. If one can defuse their ego temporarily, such rifles go on sale periodically. I decided that I'd like to build a second one as a kit, bypassing the question of parts compatibility, and investing a little bit of sweat equity to trim the bottom line. I took advantage of a Labor Day sale. The outcome was a genuine dream; a fully factory assembled Upper, as well as a full set of parts to add to a separately purchased Lower Receiver, all things together resulting in a completed rifle, for a few hundred bucks worth of savings.
Looking back a week or two later, I noted that the whole model and kit were now missing from the product lineup, and something called the
Stag 15 Varminter was now occupying that particular vacated niche. Very close examination noted two differences. The A2 Butt Stock was replaced with a nice fixed Magpul stock, and the 1/2MOA accuracy guarantee had up and disappeared. I'm going to take a winger here and guess that the new model very likely shoots the same as its predecessor, and both editions featured a nice two-stage match trigger. The new version is less than $100 more than I paid for my original Stag 6 sometime just before the Millennium, and believe that's not too bad considering nearly two decades worth of inflation.
Building the kit consisted mainly of assembling a Lower, took well under an hour, and required a few small tweaky tools that my Buddy supplied as he watched over my shoulder during my first attempt at such an effort. In all, it was a very satisfying experience, and later testing demonstrated that the two rifles shoot in largely identical manner.
I think you could be well served by starting out your building career with a
Stag 15 Varminter Kit, adding the
Stripped Lower, taking an hour or so to put it all together, and getting it all done to the tune of a bit under $900.
Whether or not it's a true 1/2MOA rifle will probably largely depend on your own skill and your choice of ammo, but I think you'll either be in that ballpark or not very far out of it when all the dust has settled.
When the day comes that she won't satisfactorily carry the mail, I strongly advise you consult with Padom; he's up on this stuff a lot better than I am.
Greg
PS, my original Stag 6 shot in the 2017 Berger SW LR F T/R Nationals MR/600yd stages here at Ben Avery Range in my Granddaughter's hands, and did respectably for a beginner in her first try at any form of F Class comp. I gifted her the rifle, and then built the kit as my own replacement. The whole experience was/is a big plus in my estimation.
