My list for black gun stuff:
First, know that the basic operating system has worked pretty darn well since its conception almost 70 years ago.
How to make them work even better:
1. Get a good barrel.
2. Have it chambered by someone who "gets this":
a. Can cut a chamber straight
b. Knows how cut threads
c. Knows how to drill a hole correctly
d. Knows how to machine a crown
3. Get new gas rings and stagger the gaps. That helps at 600+ yards. PWS and AMU proved this in the mid 90's.
-To test gas rings have a clean bolt carrier assembly and extend the bolt body until the cam pin key is all the way forward. Now carefully set it ass end up on a solid table or bench. Now "hammer fist" your hand on the table. A good hard "whack". The bolt carrier should only fall between 1/3rd to 1/2 of its total possible travel. If it falls more, shitcan your gas rings and get new ones. These are consumables and should really be replaced every barrel swap. Maybe 2x if your playing "entry team guy" with the thing.
4. Drill the gas port hole 2* off from vertical. Have it "trail" so that bullet jackets don't get peeled like onions. If your really lucky, try to time the hole in the groove. Not an easy thing to do btw...
5. Make sure the gas tube has a free pathway to engage the gas key on the bolt carrier. Pay attention when installing it so that it's not cocked to one side.
6. If the rifle sits for prolonged periods, allow the hammer to fall and replace the hammer spring with every barrel replacement.
7. OIL IT! AR's with the OEM type gas systems are known as "direct gas operation." Simply to mean that the pulse/signal from the barrel directly actuates the bolt carrier group. Nice because its simple, tolerates higher chamber pressures, and has far less complication or rate of failure when compared to a piston/op rod setup. (Sneeze a case once in an M14 or M1A due to high pressure and you'll fold the operating rod in half)
The downside is more heat at the working part of the gun. It also commands for more lubrication. Grease here only gets you so far. OIL that will emulsify solids (carbon) works better. Stinky ol CLP that's been around for decades does this really well.
-My basis for that statement: For 3 years I was an armorer and the head firearms instructor for the Baghdad Embassy Security Force contract held by Triple Canopy. (2006-2009) We were a brigade-level element during that time. I and another guy had oversight on all of the weapons systems on that contract and we ran all of the range details in the IZ and the Ankawa province up north in Irbil. 4 classes a month, 30-40 guards per class. Kurds up north shot AK's. Same thing applied.
Hot, dusty, dirty, yada yadda... Wet, oily guns worked. Dry rifles were problematic. Wet oily gun maintenance routines demanded a higher tempo. Dry guns didn't. So....choices. You either want a gun that works or a gun that is easy to clean.
FWIW, during that 3 year period, not a single post on that contract was ever downsized or suspended due to a weapons maintenance or failure issue.
Hope this helps.
C.
