hello fellow high-roaders
I am going to be building my first AR15. I’m quite familiar with AR platform, as I have quite a few.
(Armalite m15a4, RRA LAR15, DPMS, and a Spikes)
But here’s where I’m lacking experience and confidence- I’ve never built my own, so I am looking for advice on how difficult this actually may be. I already know what milspec upper I want, and it’s already put together from factory. Now I want a mil spec lower, but since I’m in CA my FFL is telling me they can sell me a lower parts kit and the stripped lower, but cannot put it together for me. Something about “putting together the lower in our shop is considered manufacturing and we are not allowed to do that here in CA”
I’m not sure if this is true, or only true to this FFL but they are a great shop and I’m choosing to go through them for my transfer of lower. So now let me get to my main question(s)
1- what is a good quality mil spec lower?
2- what is a good quality lower parts kit?
3- how much of a pain is it going to be for me (someone who’s never put together a lower receiver) to install all parts on the lower (trigger group, mag release, bolt catch, buttstock and buffer tube, etc.
4- what basic tools will I need, if any?
All information will help! Thanks guys
B
For the first time builder I think it's safe to say that assembling an AR-15 lower is much easier than assembling an AR-15 upper. Honestly, neither are very hard if you have any kind of mechanical aptitude. A lower probably takes me less than half an hour these days, though I've never really timed it to be honest. When I built my first AR-15 I did so with the help of Youtube videos (Midway USA had a start to finish video). My first build was a completely custom SBR, and I built the upper and lower. It wasn't all that hard. Just take your time, and spend the $100 or so to get the tools that will make your job a lot easier (armorer's wrench, some roll pin starters/punches, etc).
Get the mil spec idea out of your head here for a minute, too. A mil spec lower is select fire, a civilian one is not. Regardless, mil spec only means military specification, which doesn't always mean the best (believe it or not). Overall I think people overthink the lowers a bit too much. It's really just the piece that holds the other pieces together. It doesn't take a lot of stress compared to the barrel, bolt, etc. Buy a 7075 aluminum lower from any reputable brand, and you'll probably be fine with it. I've done two builds off of Spikes lowers (because my local gun store sells those) and I've done 80% lowers before. They all work about the same.
I haven't found the perfect lower parts kit (LPK) just yet. Even among the same (reputable) manufacturers I find variance between the kits. Most work just fine. Triggers are where you'll find the most difference in kits that include those. Some stock triggers are pretty smooth, some are gritty and unappealing. None compare to a competition trigger, but they're reliable and they work all the same.
For tools, here's a starter kit:
1) Roll pin starters / punches.
2) An armorer's wrench.
3) A vise block to hold the lower by the magazine well.
Like so many things, tool kits expand with time, but I think that's the only AR-15 specific tools I had when I built by first AR-15.
Anyway, you should definitely try building if you're an AR guy. It isn't that hard, you'll learn a ton about the rifle, and you'll be much more confident working on your other rifles in the future. You may also decide that you overpaid for the rifles you have, especially when you didn't get them customized exactly how you wanted them. My first 3 AR-15 variants were store bought. All of the others have been built, and I don't see myself going back to store-bought again in the future.