Local gun show had a dealer selling lowers. One lower was polymer,price tag, $25. Its FDE in color so why not.

Now I have a 20”
A 16” and a AR pistol.

I’m not exactly sure what to do with this one

Ideas anyone

16" .22LR.

quote:

Originally posted by Il Cattivo:
16" .22LR.

Yep, for a polymer lower this would be my suggestion as well.

I've heard about polymer lowers breaking. Is that an internet rumor or is that a real concern?

More of a concern than an aluminum receiver. (And those can break/wear out too.)

But still not really a concern to the average casual user.

I wouldn't use one on a serious defensive rifle, for a rifle destined for heavy use/abuse, or for something that you're planning to put a tax stamp on, but they're fine for a cheap plinker/deer stand rifle/once-every-few-months range gun/etc.

I'd caution against any hard use. I've heard of people breaking them during assembly. Monkey fisting on barrel nuts or putting strain on where the buffer tube screws in.

I'd probably only use for 22lr. If for center fire I'd expect it to break eventually.

The GWACS lowers are pretty robust.

The polymer lowers that are dimensionally identical to aluminum often break where the receiver extension threads in.

I think I might try a 7.62x39 build.

I bought a New Frontier Polymer lower to make up my own mind.
It worked well but I realized, like others, it would be best suited for a Polymer 22lr dedicated upper.
So I picked up a Chiappa Upper & it's been making cans dance ever since.

I built my ATI polymer lower as a pistol lower to house short lowers while I waited for my SBR stamps.

quote:

Originally posted by GrumpyBiker:
I bought a New Frontier Polymer lower to make up my own mind.
It worked well but I realized, like others, it would be best suited for a Polymer 22lr dedicated upper.
So I picked up a Chiappa Upper & it's been making cans dance ever since.

did the same with a US ARms complete poly lower,

did change out the FCG since the plastic hammer and trigger sucked

Chiappa .22 on a New Frontier polymer lower here as well.

Happened to the guy in the lane next to me. Scared the crap out of me.... I don't remember if he was using reloads

I didn't see a maker mentioned in the op, so it's hard to look up a track record for the manufacturer. I'd put together a 16" light weight build on it.

My FIL has one of the New Frontier ones...I'm not a huge fan, but I must admit, it's worked...so far. Moving parts seem to bind on it a little bit, and don't snap into place as positively as I'm accustomed to with an alloy lower. For what Anderson lowers are going for right now, I don't see any reason to buy a polymer lower....in fact I recommended that he pick up an Anderson and we'd swap the parts out.

quote:

Originally posted by DCFD4:



Happened to the guy in the lane next to me. Scared the crap out of me.... I don't remember if he was using reloads

This looks like an FMK lower.

Yup, that's where they break, the weak area that gets high stress wher the RE attaches. It isn't about the recoil so much, but the stresses placed on the stock transmitted to that area (lots of leverage on the stock).

Not all polymer lowers are alike though, the TN Arms brand has this area reinforced as well as some I believe brass inserts.

I'd do a lightweight .22lr build. 16" pencil barrel, LW upper with no FA or dust cover etc.

hope that dude (and everyone else near him)were all ok,


friend put a standard 556 upper on his USArms and put a few hundred rounds thru it,
no issues,

I , at the time, had plenty of standard lowers and guns built, so just kept one for myself and put the inexpensive 22 upper on it,

Looks to me, IMHO, that it is a total waste of time to try same, when you can get a 7075 lower for $30. Plastic breaks.

The magwell completely disintegrated. There were pieces of plastic embedded into the wood below... Could've caused some serious injuries