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FPembleton
06-29-08, 13:45
I've recently picked up a 10.5" RRA 9mm upper and lower. It was not factory built, but assembled by the dealer, and did not come with a manual.

I'm familiar with .223 ARs, but the 9mm blowback ARs are a bit different. Especially the bolt carrier. I was wondering how you properly clean and maintain the bolt. I haven't been able to find any scanned manuals of 9mm ARs anywhere.

Can anyone help me out? Thanks.

Walnut
07-22-08, 21:58
Hello, I have a 16" RRA that I have been playing with for awhile now, these are the things I have done to my bolt. I was having some feeding problems when I first got the gun, but now it running like a top. I figure that it easier for me to tell you what I have done for my gun to make it run good. Some may be over kill, but I runs good, so I have no complaints.

1. The standard recommendation is to replace the roll pin that holds in the extractor with an better one. Go to a hardware store and get a 1/8"x3/4" roll pin and replace the factory one (i got mine at Lowes). I find It is easier to start at the top and drive it out the bottom and start the pin at the top and drive it out the bottom. You'll get extra pins and you need them.

2. Now I am super cheap and shoot cast bullets out of my gun and various other reloads, so my gun gets pretty nasty. I like to remove the extractor every 500 rounds and clean it out, pull out the firing pin too at this time. Watch out for the spring loaded firing pin. It nearly went across the room. One tip I can give is, I crimped the last coil on the spring so it would stay on the firing pin. Now when you shoot it across the room, you keep the firing pin and spring together! I will take a Q-tip with a drop of oil and run down the firing pin channel to clean it out. That is all I do for that. I have discovered that oil in the firing pin channel causes light strikes on guns in general. I live in a dry climate so rust isn't really much of a concern.

3. Extractor tension was a factor in my gun running smoothly. I run a 8oz buffer and was having extraction/ejection issues, I would have empty casings staying in the gun with factory 115 FMJ ammo and get these gosh-awful jams. It got worse and worse to the point that I would get 3-4 jams per magazine. So I did step 1 and also tightened the extractor. The extractor is just like a 1911 extractor, (check google,there is tons of tips on how to tighten it.) I just stuck a case in before and noticed how much of a "bite" there was and just bent the extractor a bit more until I got the tension up. My check was pretty high tech , put a loaded round in it gave it gentle whack on a open hand and when the loaded bullet didn't fall out, I stopped. (hold the bolt upright when you do it)

4. Polish the extractor (use a dremel tool with a soft wheel. YOU DON'T WANT TO REMOVE ANY METAL, JUST POLISH THE EXTRACTOR HOOK. Makes cleaning much easier.

5. Polish the whole bolt face with small felt bob. YOU DON'T WANT TO REMOVE ANY METAL, JUST POLISH THE METAL. I do this for easier cleaning

6. Make sure the carrier key is tight.

7. I also lightly polished the slot on the bottom of the bolt where the ejector rides (my gun likes the ejector to ride gently against the bolt). Makes the cycle a bit smoother and polish the area where the bold rides against the hammer.

8. Polish up the feed ramp in your lower. I am using a dedicated Hahn Unit.

9. I pulled the barrel out of the gun and polish up the chamber with some #0000 steel wool/oil and polished the breech face of the barrel. This was done just to make the cleaning easier. The breech of my gun gets pretty nasty so by polishing it, the clean up is much easier. The only reason I polished my chamber was that I got some light reamer marks on my brass.

Well, that about it off the top of my head.

Cheers

Walnut

BoyScout4Life
06-21-09, 20:57
Thanks, Walnut...Very Informative, with great tips. I will use them all...:)

davidk
07-19-09, 00:50
Thanks! Great suggestions