AR / 9mm Question

[kricket37]

For my fall project I am looking at building an AR lower and put a 9mm RRA upper. My question to the forum, what should I be aware of when building the lower. I am guessing a trigger spring, hammer and possibly a different buffer in the stock. Am I missing anything? Do they make LPK in the 9mm variety? Would the 9mm lower also work for a 40S&W lower? I was hoping to pick up another Spike's Tactical stripped lower this weekend at the 1500 and a LPK.

Thanks,

Kris

 

[jd4320t]

I think it's just a hammer and buffer change and you have to have a 9mm mag block.

 

[absrio]

With a ramped bolt you can use a standard hammer. With a standard 9mm bolt you have to use a 9mm Hammer. Everything else in the LPK is the same. You will also need a 9mm buffer. Rock River sells factory ones or you order a heavier one from Spikes (which I did.) If you going to build a 9mm do the fun route and build it a SBR. You will have more fun with it and its only an extra $200 into the build.

 

[dross]

What's the downside of just using the buffer tube end as a stock? Quite a few people seem to put foam covers or cane tips on the end. Seems like it would work pretty much the same.

 

[absrio]

What's the downside of just using the buffer tube end as a stock? Quite a few people seem to put foam covers or cane tips on the end. Seems like it would work pretty much the same.

IMO that is just to questionable (you know the whole constructive intent thing.) If you want to start off with a short barrel and a pistol, get a pistol tube. About $40 or so.