Battle cleaning an AR-15

Your friends want to go shooting today. Then you remember: last month roughly 1000 rounds of cheap, dirty Russian ammo went through your favorite AR-15, and it's still filthy.

This isn't a full teardown-and-clean guide. It's what to do when the rifle is choking in the field and you need it running again right now.

Where this comes from

Shawn, who wrote the original, wasn't infantry (a POG, short for "person other than grunt"). Still, he put plenty of time on an M16A4 firing blanks. Blanks are the worst: all the dirty powder, and no bullet to carry any of it out of the barrel. The AR's direct impingement gas system already blows that gas back into the action, and blanks make it far worse. On field exercises the rifles had to keep running all week, burst after burst on the M16A4's 3-round burst setting.

Clean the bolt

If you can clean one part, make it the bolt. Only the bolt, not the whole carrier group. In the military's reassembly check you hold the assembled bolt carrier group and flick it, to make sure the bolt slides in and out of the carrier freely.

The bolt carries small gas rings. Gum them up and everything stops. Keep them clean and the rifle should run. Shawn has brought an AR back into action by wiping the bolt on a T-shirt, no lube at all.

Why it works

When the rifle fires, a burst of hot gas comes through the gas key and drives the bolt to unlock, extract and chamber the next round. If the gas rings are dirty enough to stick, the bolt stays locked with the empty case still in the chamber. That's your jam.

Then clean it properly

A field trick is a field trick. When you're not in a fight, look after your tools. Clean guns run happy. Until then, pull the bolt, wipe it on your shirt and keep shooting.

Cleaning kits, solvents and lube: shop cleaning gear.