Dumb ar-15 question.

[Rock_Steady]

So I'm wavering right now on whether to get an AR-15. Partly cause of the bills in the house and senate, partly cause I like them - I just don't have much utility for one right now. Anyhow, my question is - if I buy a mil-spec stripped lower and put that together with a parts kit, can I pretty much but an upper in whatever caliber I want and have a ready-to-go system? I'm just looking at the possibility of maybe .308 instead of .223, or a 9mm upper. Not looking to go huge, but wanted to have the parts around in case I wanted one later and they are very difficult to buy. What do you think?

 

[Logan5]

Well, sure, you can do it that way. The thing is, sub caliber uppers differ in the magazines they use, and the inserts/whatever they pop into the magwell to accommodate whatever mags the manufacturer has decided to run in that caliber.
You've got a good idea here, but the thing is to shop for uppers carefully once you go foreward with this, or you risk blowing the savings vs buying a low end .223 AR plus whatever other uppers.

 

[funfaler]

The 308 lowers are different from the 223/9mm/7.62x39 lowers. Also, unlike the 223 lowers, not all 308 lower/upper combinations will work together. Most of the 308 lowers will only work with the same brand 308 upper.

So, if you are going to go 308, better off getting a complete rifle, or atleast identifying the brand you want.

If you get a 223 lower, then brand means little if you wish to build later.

I would not count on any new laws "allowing" the grandfather of guns, receivers or parts, just my opinion. If you want something, my bet would be to get it all now, as well as the mags you are going to need in the long future.

Good luck