I won a couple of FMK polymer lowers on gunbroker for 99 cents each after shipping and transfers I am into them $40.99 each, about retail. I have never messed with the ar platform but have an sks with plenty of ammo, 7.62x39 it is. Started pricing barrels, stripped uppers, bolt carrier groups, etc and I thought to myself this might get expensive. I won a lower parts kit with a handle on gunbroker 40 bucks shipped and now I am fully committed. While scouring gunbroker I found bear creek arsenal, I went to their site and they were having a sale. I got the BCA Dual Charging AR-15 Complete Upper Assembly 7.62x39, 16" 4150 Parkerized Heavy Barrel, 1:10 Twist w/ 15" Lightweight Keymod for $270 shipped. I bought a stock and buffer tube as well as a couple 30 round mags from classic firearms for 75 bucks shipped. I got kit off ebay with a lower vise block and the ar wrench for 30 bucks shipped.




So tell me THF is a 460 dollar ar a true budget build or could I have gone cheaper? How long will the polymer lower last? FMK says they have a lifetime warranty on their lowers hopefully I wont have to find out.

ChrisG, I broke a poly lower a month or so back that I've been running for 15 years. I feel pretty confident it broke because of my hot loads, suppressor, and overgassing. Yours should last a while.

In case you get light primer strikes and fail to fire, swap your hammer spring to an extra power hammer spring. I don't know if BCA installed an enhanced firing pin with your upper but that also helps with light strikes.

That's good to hear. I will be shooting factory ammo. Like most things there are so many different opinions on the internet. Did it break where the buffer tube screws into the lower?



I had read about the light strikes. Depending on what happens I will either get the upgraded spring kit or just get a drop in trigger group. There is one on ebay for like 75 bucks.

Ebay Trigger

No, it broke the rear take down pin and on the inside of the lower, took a chip out where the pin goes.
https://texashuntingforum.com/forum/ubbthreads.php/topics/7430243/re-over-pressure#Post7430243

To your question of could you have gone cheaper yes you could have but you didn’t do bad either. I’ve built one for 320 but that took months of searching for deals and it’s shoots every bit as good as some other much more expensive ones. And I didn’t use all new parts either though.