Is your direct impingement AR15 / M4 rifle overgassed or undergassed? How can you even tell? Chances are your rifle is overgassed and I can show you an easy way to tell.
A great solution to overgassed weapons is the Superlative Arms Adjustable Gas Block. I’ll walk you through how to tune your rifle. Creating the highest reliability with the lowest recoil impulse.
You can find the SA Adjustable Gas Blocks here.