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Posted: 2/19/2007 1:30:22 PM EST
Does anybody else use a RRA 2 stage trigger in their pistol caliber setups?

I've found that I sometimes get doubles and tripples with my trigger both with my Oly arms 9mm and 45ACP set ups.

Since my inital try with my 9mm I did a full tear down cleaning on the entire rifle. This seemed to help things but after about 200 rounds it started back at it.

I tried this trigger in my Oly arms preban lower and my Vector arms CA "off list" tinkering lower with the same results when used with my 9mm uper.

I tried the same set up with my DPMS stock trigger (I know, I know...) and it worked perfect with no unsettling bursts.

I have since removed my RRA 2 stage trigger and will only use it with my 223 caliber rifle. It has absloutely NO issues with doubles or tripples when shooting in a 223 upper.

Anybody else ever experience this? Am I just out to lunch and missed some important part of some other thread here?

I have no intention of using this trigger ever agian with my 9mm or 45ACP uppers. Should I think about contacting RRA about this though? Maybe its just a defective setup?
Link Posted: 2/21/2007 1:18:14 PM EST
Today, I fired my .22 AR-build for the first time (it is described in another thread, look for "Bushmaster .22LR upper, RRA NM trigger, and low-mass hammer" as the thread title). I had LOTS of problems: One slam fire (!) upon closing the bolt, a few FTF probably caused by the mag not being exactly in the correct position (the Bushmaster plastic mag seems somewhat out of spec), many failures to fire due to light primer strikes. Most of the time, the rifle was able to eject the spent shell and strip another one and chamber it, but no single time did the bolt carrier successfully cock the hammer. And unfortunately, ARs don't have a cocking handle that doesn't also eject the load (what a pain).

My theory is that the bolt carrier is going too slow, and even though it gets far enough back to operate the extractor correctly, and load the next round correctly, it gets stopped by the hammer, without cocking it.

The thing that's relevant to your question is: I got one doubling. I was testing usually with magazines with 2 rounds in them (for safety reasons, in case the rifle goes full auto on me), and in one case with Winchester Dynapoints (*), both rounds were fired. The cyclic rate seems extremely high, there was no audible gap between the two rounds. My theory is that the second shot was probably a slam fire, or maybe the hammer was pushed far enough back to come flying forward again, but not far enough to latch onto the disconnector or sear. In either case, this could explain the problems you are seeing too: I think the RRA NM fire control system requires the hammer to be pushed back quite far and with considerable power to latch, and with weaker rounds that might not always happen.

The weird thing is that all the other ammo I tried was much more high-powered (Aguila Supermax, CCI Stinger, and CCI Minimag), and I would have expected doubling if any with high-powered ammo. Weird.

Unfortunately, I ran out of time today. My course of action is going to be detail-stripping lower and upper, clearning everything super-carefully again; there seems to be a lot of grit in the moving pieces, and when looking carefully I even found some aluminum filings. Then reassemble and lubricate again. Also, I'm going to try to obtain a weaker hammer spring, or weaken one by bending it. And polish a few moving surfaces with a dremel tool.

(*) Why do I like Win Dynapoints? They are cheap, easily available (Walmart), subsonic = quiet in many rifles, and pretty accurate.

Note: I'm a complete beginner as far as ARs are concerned, so take the above with a large grain of salt.
Link Posted: 2/26/2007 9:20:08 PM EST
[Last Edit: 2/26/2007 11:02:24 PM EST by gunrun45]
Nobody else has a RRA 2 stage in a pistol caliber build?
Link Posted: 2/27/2007 3:55:25 AM EST
Link Posted: 2/27/2007 11:01:13 AM EST
Thank you for the reply. I had no idea that some triggers were not designed to work with some calibers (my bad). Thank you for the clarification.
Link Posted: 2/27/2007 4:41:20 PM EST

Originally Posted By gunrun45:
Does anybody else use a RRA 2 stage trigger in their pistol caliber setups?

I've found that I sometimes get doubles and tripples with my trigger both with my Oly arms 9mm and 45ACP set ups.

Since my inital try with my 9mm I did a full tear down cleaning on the entire rifle. This seemed to help things but after about 200 rounds it started back at it.

I tried this trigger in my Oly arms preban lower and my Vector arms CA "off list" tinkering lower with the same results when used with my 9mm uper.

I tried the same set up with my DPMS stock trigger (I know, I know...) and it worked perfect with no unsettling bursts.

I have since removed my RRA 2 stage trigger and will only use it with my 223 caliber rifle. It has absloutely NO issues with doubles or tripples when shooting in a 223 upper.

Anybody else ever experience this? Am I just out to lunch and missed some important part of some other thread here?

I have no intention of using this trigger ever agian with my 9mm or 45ACP uppers. Should I think about contacting RRA about this though? Maybe its just a defective setup?


OLYMPIC ARMS pistol caliber uppers are designed to be used with the standard 223 trigger and hammer group so the RRA trigger group should work fine . RRA and Colt pistol caliber uppers need a specific hammer or you can ramp your bolt and use the same 223 hammer .
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