80% Polymer lowers 'Lifespan'

[mif_slim]

Magpul and Glock get in the poly AR scene and itll be proclaimed the best AR ever made by 95% of gun shooters as well as LE.

OP, different makers different "lifespan". However, compare polymer lowers today to back when it first started, its come a long way.

[TS77]

maybe the latest generations 10 years from now.

[.45 ACP]

Funny thing, most of the people commenting here have yet to actually mill a polymer lower out and build one.

I have a poly lower from Tenn Arms, and a G150 Gen 2, both milled from 80s. Neither has cracked, imploded, or disintegrated after 1500 rounds each. There's a video on youtube where a Tenn Arms lower was run over by a 2 ton truck and it didn't crack and was still usable afterwards.

[TMB 1]

Funny thing, most of the people commenting here have yet to actually mill a polymer lower out and build one.

I have a poly lower from Tenn Arms, and a G150 Gen 2, both milled from 80s. Neither has cracked, imploded, or disintegrated after 1500 rounds each. There's a video on youtube where a Tenn Arms lower was run over by a 2 ton truck and it didn't crack and was still usable afterwards.

Which one do you like best and what did you put on them?

[BrokerB]

Getting ran over by a truck is. It the same as getting an explosive force delivered? I have seen people ran over slowly by trucks and live too. You ever seen a guy get hit by a truck going 80mph ans live..hardly.

That video is parlor tricks.Its like As seen on Tv infomerical.

If you want to rely on the cheapest rifle for home defense, that is very poor decision making.

I surely expect "plastic" to become more in use, but for now i will regulate plastic rifles to recreational shooting.

[WallySparx]

A thousand rounds and change thus far through my New Frontier lower and absolutely no issues.

[Barleyologist]

Getting ran over by a truck is. It the same as getting an explosive force delivered? I have seen people ran over slowly by trucks and live too. You ever seen a guy get hit by a truck going 80mph ans live..hardly.

That video is parlor tricks.Its like As seen on Tv infomerical.

If you want to rely on the cheapest rifle for home defense, that is very poor decision making.

I surely expect "plastic" to become more in use, but for now i will regulate plastic rifles to recreational shooting.

As stated earlier it is not going to be used for home defense and this is not about price. This is merely about knowledge of lifespan.

[paratroop]

I had a poly 80%, dont remember what make. I gave it away before i ever even thought about milling it out. My buddy decided he will turn it into a dedicated 22. I said, good idea!

Alright this has nothing to do with poly guns, but has anyone seen the amercian spirit arms 9mm lower? Pretty slick, expensive, but slick! No adapter needed, takes glock mags.

[tuolumnejim]

Seen some the early one's not last through a box of ammo.

[DoubleTap76]

I mean really, what is there to "fail" on a lower.

It only holds the trigger assembly. Big deal. Most of the magic happens in the upper receiver. Not sure how it's different from any polymer pistol.

I do know that with the 3D printer versions, they tend to fail (brake) where the buffer tube action goes down. I see that far less likely with a good polymer. Maybe reinforce that area some how. Of course, I could understand how you might want to avoid butt stroking someone. But who is getting into hand to hand combat with an AR these days?

I can't bring myself to buy a Polymer lower yet but, it isn't really for any rational reason. I could definitely get behind a 9mm lower.

Any additional thoughts???

[.45 ACP]

Which one do you like best and what did you put on them?

I'll post some photos when I get home, but I did a G150 Gen 2 and Tenn Arms with brass inserts both as 223/556 builds.

On the Tenn Arms lower, I had to dremel and open up the mag button hole a bit because it was tight as an 18 year old virgin. 5 minute job and now it's perfect.

On the G150 Gen2, the bolt release wobbled a bit so I had to use a small plastic washer to tighten it up.

Other than that, I love the weight of them, and have put enough rounds through them that I'd trust them for home defense (not that I'd choose an AR15 to go after a thief in the night).

The best part is I can grab a Polymer 80 and mill one out in about 20 minutes in the garage with some country music in the background. Try that with a 7075 forged.

I do have 7075 lowers, but they require a lot more babying and skill IMO to do correctly.

[Barleyologist]

Yes!

I second that!

[ElvenSoul]

Usually what fails is the pins and buffer tube threads.

TN Arms eliminated the most common failures by using steel inserts.

[Calif Hunter]

I put an AR together with an FMK polymer lower for my teenage son and it has worked very well for thousands of rounds. His AR is very light and handy and is very accurate (more a function of the barrel and upper.) He uses it in 3-gun competitions monthly plus lots of plinking, hunting and other recreational shooting. It has not failed in any sense at any time.

[homelessdude]

So far I have welded one of the sheet metal lowers together, done a few 80s in 7075, one in 6061 and two 80% polys. All of them work just fine and were a lot of fun to do. The polys were by far the easiest to do. For 59.00 it came with the jig, the drills and the end mill. I have had no problems with them. I even cut up the jig and used it on an aluminum one. It worked but not real well. You could push the plastic jig around when milling the aluminum if you weren't real careful. Hope it helps.