The Average Armory: The AR-15 Build: Recoil Spring and POF Roller Cam

So after doing some additional research, I found that both my original spring and cam selection may have been misguided.

I want this gun to be something of a hard working tool, and not so much a "gamer's toy" that might be more finicky in terms of reliability. As such, I decided to go with a full power recoil spring. Further reading suggests that flat wire springs might be a better alternative to conventional round wire springs.

Strike Industries claims increased forward bolt load and reduced compression force, along with higher spring life compared to its MilSpec counterpart. What this means is that it closes the bolt with more force while being easier to cycle the action. This is made possible because of the flat wire design, allowing for the spring to be physically longer which means spring strength can be adjusted. Either way, the longer spring life and reduced "twang" is what sold me.

As for the cam, it turns out that some piston AR's suffer from something called receiver gouge. This issue is common enough in piston AR's that POF decided to make a special cam pin that helps to reduce the chance of developing receiver gouge.

The top of the cam pin is basically a roller bearing instead of a flat piece of metal. This means that if the cam pin were to contact the upper receiver, the bearing would, in theory, roll along the receiver while a standard cam pin might scrape and dig into the receiver. Looking at pictures of rifles with receiver gouge was enough to make me order this part. At the time I ordered this, most everyone was out of stock. I was impatient and ordered it, and now you can find better deals all over the place. Learn from my mistakes, you don't need to order non-critical parts until you absolutely have to. Even if I completed the rifle, I could have run the regular cam until I got a better deal on this.

As my build list now stands:

Brownells