Came across this online and thought people may be interested. I don't know anything about this seller however.
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Tennessee Arms is excited to bring to market our light-weight incredibly strong AR-15 style lower receiver. Manufactured from a high strength Nylon blend with a rediculous amount of fiber reinforcement you will be amazed by the strength and light weight. The colors are molded in to the receiver so you will never have to worry about a scratch or use marring the finish. We reinforce our receivers using our patent-pending technology that includes Marine-Grade Brass inserts that are permanently molded into our lowers. These metal threaded inserts give our receivers the strength needed without sacrificing the weight savings of the composite bodies. The end result is a lightweight, tough as hell receiver you can depend on. To back that up we offer a lifetime guarantee on all our products. We invented the hybrid lower receiver, and have been working on making sure it stays the best on the market ever since.
The TN-Arms 15 is a Nylon bodied AR-15 style lower receiver that has additional metal threaded inserts for strength . This stripped receiver is designed to accept any mil-spec lower parts kit. All colors are molded directly into and throughout the entire receiver so you never have to worry about wearing it off unlike a painted finish. This model sports a redesigned bolt catch area , a repositioned buffer retainer, and all the upgrades we made from previous models. Customers boast about how quickly their builds go together, and this is from the upgrades that customers asked for and we provided. Tennessee Arms will continue working after the sale to improve upon the design to further help you with your future build plans.
Nylon 6-6 Body Marine Grade Brass inserts in Buffer Tower and Pistol Grip Lifetime Warranty against Breakage or Failure Available in Magpul Matching Colors 5.6 Ounces Stripped!!!!!!
Like anything, the tech is getting better. It stands to reason that the "better" mousetrap is coming.
The Glock (plastic) pistol would never last, or that was the rumor in 1983...
The early Plum, Bushmaster, and such were plagued with breakage rumors at the receiver extension, the front pivot lugs, and the pivot pin holes.
I have seen a few of the broken ones, but have not owned one to take it to breakage. Some of the breakage I've seen was general abuse, some was incorrect installation, and some was just plain WTF.
While they are "OK" for light use, they are not generally accepted as a EDC platform. YMMV.
For the difference in price, I've stuck with the metal lowers by choice.
My worry about the Windham CF lowers would be will they react to a fracture like carbon arrows are reported to do, as in pretty much explode when shot from the bow? Are the lowers exposed to the same forces that a carbon arrow is when shot?
The forces are applied in way different areas. Most lowers I've seen were split or cracked from stress.
The carbon arrow has "X" amount of force pushing the mass from behind, and the shaft can't handle the stress before the arrow moves (mass at rest), it splinters into the fiber bundles. OK, one of the physics majors can explain it better...but you get the idea.
Majority of the "force" in an AR is in the barrel and chamber, contained by the locking lugs on the bolt. Sure, the uppers and lowers will split if the rifle fires out of battery, plenty of Google Fu showing the results. Same with the Glock pistol. Unlike the carbon arrow, the polymer formulas are designed to stretch and split, not fragment.
The BCG cycling from the gas systems, and the buffer and spring slamming back and forth stress the pins in the lugs on the lower. The receiver extension is stressed by the buffer operation, but rarely "explodes".
I can think of four poly lowers I've seen, one had a cracked receiver extension ring. The claim was it broke while shooting, but it could also have been over-tightened during assembly.
Two had the front lugs cracked or broken, the owners claimed from normal firing at the range.
One had a crack by the hammer pin hole, but could have been a mis-aligned "bigger" hammer job on the bench.
Came across this online and thought people may be interested. I don't know anything about this seller however.
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Nylon 6-6 Body Marine Grade Brass inserts in Buffer Tower and Pistol Grip Lifetime Warranty against Breakage or Failure Available in Magpul Matching Colors 5.6 Ounces Stripped!!!!!!
A buddy and I each bought one of these recently. I bought mine for a lightweight build, and it's OK for that, but honestly I won't be buying another.
They are pretty rough; lots of casting seams everywhere, lots of flash and burrs that need to be trimmed off. Both of our receivers had to have material removed to fit an upper, not flash but the body of the receiver itself had to be ground down.
We put an hour or two of work into each receiver to make them functional, and I still would not consider them nearly the quality of a $50 blem forged lower.
Also, it's worth noting the brass inserts are only for the threads, they don't really reinforce the buffer tower.
I bought a Patriot complete poly lower assembly for the heck of it(pretty light as the complete lower is poly, the only metal parts are the springs, buffer, plate, castle nut, bolt catch, and trigger pins). I've broken two of their poly rec ext on the first two range sessions with it. One lasted 30 rounds, the other 5! I put a aluminum rec ext on it along with steel take down pins, but haven't tried it since. I'd never trust it for serious business by any means. For messing around at the range it would probably be ok.
While I have no direct experience with this particular receiver, I do have a background in polymers and molding and can say this:
1. These lowers are produced from Nylon 6/6. Now there are many different grades of this polyamide and it is produced by several compounders worldwide so it is hard to say that the one they are using is the *best* blend for the application......however, as a general rule 6/6 is very tough and can take impact loads quite well. It also has good chemical compatibility for all things involved in cleaning a gun.
2. Their website mentions that they use a lot of fiber reinforcement. This is typically fiberglass and at a rate of 5% - 40%. Glass does add additional toughness and rigididy to plastic....especially Nylon....but if you go too high it also can become brittle. Lots of glass can also make the plastic difficult to mold uniformly.....although, with proper part and tool design, this can be overcome.
3. They claim to use brass inserts. This is where the big difference could be. Properly designed and located molded in inserts - threaded for the pistol grip and bushings for the pivot and rear pins - may make these receivers worth a look.
While I have no direct experience with this particular receiver, I do have a background in polymers and molding and can say this:
1. These lowers are produced from Nylon 6/6. Now there are many different grades of this polyamide and it is produced by several compounders worldwide so it is hard to say that the one they are using is the *best* blend for the application......however, as a general rule 6/6 is very tough and can take impact loads quite well. It also has good chemical compatibility for all things involved in cleaning a gun.
2. Their website mentions that they use a lot of fiber reinforcement. This is typically fiberglass and at a rate of 5% - 40%. Glass does add additional toughness and rigididy to plastic....especially Nylon....but if you go too high it also can become brittle. Lots of glass can also make the plastic difficult to mold uniformly.....although, with proper part and tool design, this can be overcome.
3. They claim to use brass inserts. This is where the big difference could be. Properly designed and located molded in inserts - threaded for the pistol grip and bushings for the pivot and rear pins - may make these receivers worth a look.
I can feel myself ordering one as I type.....
My background is in breaking parts as a test and development engineer, and I occasionally get to work with this material as well, and can second your comments.
The TA receivers do appear to be glass reinforced Nylon; the material itself is pretty tough.
Where they fall short is the fit & finish quality. Most other parts I've worked with in this material professionally have much better finish, with seams lined up correctly, minimal flash, etc, but not so with TA. You'd think they could at least check to make sure they fit an upper before shipping them out, but apparently not.
I have 2 of TA's lowers currently on rifles, I have 2 more I'm slowly putting together (for the grand daughters) and I have 3 more on order for future projects.
The lowers may need a little tweaking to fit against the upper back at the butt stock but the tweaking is as simple as using a file to get the right fit. The color is molded in so you cannot see where the polymer is removed.
Yes, the lowers do have brass inserts in the pistol grip and where the butt stock tube screws in.
They are coming out with a light weight 308 lower as well.
For liberals and anarchists, power and control is opium, selling envy is the fastest and easiest way to get it. TRR. American conservative. Never trust a white liberal. Malcom X Current NRA member.
Complete and utter junk...and I dont need to touch one to make that determination. The only polymer lower that is even remotely considerable for any sort of serious use is the Cavarms unit, which made no effort to directly copy a design intended for aluminum to an inferior material.
I agree that a clear lower would look pretty cool.....but unfortunately, unless the lower profile is highly modified (complete redesign) this is unlikely....at least to compete in today's market.
Once you add glass to the polymer to increase its strength, optical clarity is a gonner. So even if these were shot from Polycarbomate (bullet proof glass, eyeglasses, etc) and the mold was polished to produce an optically perfect part, the glass fiber required to stiffen it up would make the part opaque.
Kwg020....I would love to see pics of the final builds if you don't mind sharing.
I agree that a clear lower would look pretty cool.....but unfortunately, unless the lower profile is highly modified (complete redesign) this is unlikely....at least to compete in today's market.
Once you add glass to the polymer to increase its strength, optical clarity is a gonner. So even if these were shot from Polycarbomate (bullet proof glass, eyeglasses, etc) and the mold was polished to produce an optically perfect part, the glass fiber required to stiffen it up would make the part opaque.
Kwg020....I would love to see pics of the final builds if you don't mind sharing.
M1919, I sent you a PM.
kwg
For liberals and anarchists, power and control is opium, selling envy is the fastest and easiest way to get it. TRR. American conservative. Never trust a white liberal. Malcom X Current NRA member.
Fiber reinforced clear plastic should look something like fiberglass mat, the kind that's oriented randomly, not the woven stuff. I doubt you'd see through it at all, unless the fibers turned clear with the plastic, like fiberglass can do.
