Anyone AR Poly Receiver Fans have experiences with the KE Arms KP-15 Receiver? Good, Bad or Otherwise?

[arakboss]

KE ARMS LLC AR-15 KP-15 STRIPPED LOWER RECEIVERS POLYMER | Brownells

What makes this stripped lower different? The answer is simple… the KE Arms KP-15 stripped lower receiver is a monolithic polymer AR-15 style lower receiver made from injection molded, 30% glass-filled nylon. Its unique design incorporates the buf...

www.brownells.com

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[Stomper]

Poly AR lowers ….. instant no-go IMHO.

 

[VinnieBoomBah]

From what I have heard they are the rebirth of the old CAV ARMS lowers and are one of the only worthwhile "poly" lowers out there

 

[arakboss]

From what I have heard they are the rebirth of the old CAV ARMS lowers and are one of the only worthwhile "poly" lowers out there

I am thinking about trying one with quick change barrel project upper. I have never owned or used a poly AR lower before.

 

[VinnieBoomBah]

Still kicking myself for not picking up that glow in the dark Zombie CAV ARMS lower when I had the chance

 

[Will_White]

In general poly lowers are a no go. The KE arms is the exception, its alot beefier in the areas that matter and it doesn't have the fail points of standard poly lowers (stock attachment, and grip attachment.) Trade off is you're stuck with a fixed stock and grip.

 

[arakboss]

In general poly lowers are a no go. The KE arms is the exception, its alot beefier in the areas that matter and it doesn't have the fail points of standard poly lowers (stock attachment, and grip attachment.) Trade off is you're stuck with a fixed stock and grip.

The stock would be fine with me. It sounds like you are limited to carbine buffer/spring combos but that shouldn't be an issue with a gasless upper.

 

[Stomper]

The holes for the take-down pin is sketch AF……

 

[Nick Burkhardt]

So far all good for mine matted to a PSA pencil barrier upper. About a pound lighter than a traditional AR build.

 

[arakboss]

The holes for the take-down pin is sketch AF……

This local (to Oregon) gent discusses the sketch AF pins at the 6:10 mark in this video.

 

[P7M13]

Poly AR lowers ….. instant no-go IMHO.

+1
Most polymers age harden and become brittle.

 

[dinky450]

I got a 80% poly lower. Was able to router it out in 5 mins flat. Seemed to be alright for short term use but still seems too soft of materials to hold up. I could see pins getting loose over time. For the amount of weight saving which isn't much I wouldn't run one.

 

[Will_White]

The holes for the take-down pin is sketch AF……

What's your issue with them?

 

[osprey]

I have a poly lower on a 22lr build and I think it is a good fit as it doesn't have stress on the receiver threads from the bolt carrier reciprocating. I would never use a poly lower for anything serious although the KE seems to solve the most pressing issue of the lower receiver buffer tube thread weakness.

 

[monkeybutler]

I guess I don't understand why someone would look to a polymer lower when aluminum ones are cheap (if you wanna go cheap) and don't weigh much more. I also prefer to choose my own stock and grip.

 

[VinnieBoomBah]

I guess I don't understand why someone would look to a polymer lower when aluminum ones are cheap (if you wanna go cheap) and don't weigh much more. I also prefer to choose my own stock and grip.

Because they can?

 

[Newberg]

I've owned many many of the Gen 1 and Gen 2 CAV Arms lowers. I still have 5 of them and they are probably 15+ years old at this point. Zero issues.
Check the link below for more data.

CAV-15 MKII Durability and Longevity

The flagship product of Cavalry Arms Corporation was the CAV-15 polymer lower receiver, and later starting in 2003 the CAV-15 MKII lower receiver. You can read all about the design history of the …

www.google.com

KE Arms is the next generation of CAV. I would trust them completely.

 

[Stomper]

What's your issue with them?

Long-term and short-term physics… that's wut.

 

[arakboss]

Long-term and short-term physics… that's wut.

So the medium-term physics are OK with these

 

[Will_White]

Long-term and short-term physics… that's wut.

I'm not seeing how these would be different then pins on any polymer frame handgun. The two failures I'm aware of, one the buffer wasn't right and split the weld in the back which they're using a better process for now, and the other was an explosive reload that took out pretty much the whole gun and while an aluminum lower might have survived it could have just added to the shrapnel.

The cav arms lowers literally got ran over by a truck and still worked fine which couldn't be said for the other rifles in that incedent.