Piston vs. DI in the AR

Piston vs. DI

I have no problem with a well done piston system on an AR. I don’t think they’re a quantum leap forward or a panacea. If someone were to hand me one of the better piston ARs I’d go to work and not worry about it. Of course, I’d say the same about the direct gas impingement system.

However, here are my opinions on the piston system in general (in an AR).

It makes the weapon heavier, more mechanically complex, more expensive, and less accurate. The positives are better short term durability and more rounds before you get cook-offs. The side load on the carrier means an increase in wear which adversely effects long term durability. Plus, the weapon is still not sustained fire capable as it doesn’t have a quick change barrel. The action and gas system may stay cooler and cleaner but you’ll still be able to wash out the barrel with those long bursts.

Rather than go with a piston AR, I can go with a refined AK and get the supposed advantages in a weapon that is lighter, less complex, more durable and less expensive than a DI AR (albeit less accurate).

Frankly, the differences between the two systems in the field are minor.