Rock River LAR-40 FCG proprietary?

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  • slsc98

    Ultimate Member
    May 24, 2012
    6,746
    Escaped MD-stan to WNC Smokies
    This is a question for Chad or any other members who may know:

    Are the fire control groups in Rock River .40 cal AR’s such that one canNOT drop in, say, a Geiselle SSA, PSA “Enhanced” or other after market trigger and hammer assemblies?

    I seem to recall reading that somewhere (possibly Rock River’s own website although I wasn’t able to relocate any such language this evening) ...

    Reason I ask is I have been sitting on a half dozen or so Geiselle SSA packages and a couple Palmetto State Armory “Enhanced” (the little bit smoother $49) trigger / hammer packages for a couple years now; and, after spending this evening (finally! :sad20:) dropping them all in host rifles or pistols I wound up with one left over.

    And that Rock River LAR-.40 is sitting in the corner staring at me ... :innocent0

    And, fwiw, the stock trigger pull on that Rock River .40 cal AR is not only last bad as squeezing wet sand between your fingers it will onl y read on a trigger gauge that has a gradation for “SVCKS!” :mad54:

    Thanks in advance, “advice being an answer you don’t really want to hear,” and all ... :lol2:
     

    outrider58

    Eats Bacon Raw
    MDS Supporter
    Jul 29, 2014
    49,818
    I'm not sure if this will be of any help. I have a RRA 9mm bolt in my SBR. I seem to remember back then, they were converting to "ramped" bolt carriers for PCCs. I got the ramped one. I think I just through a FCG that I had on hand. It looks very much like this Andrson FCG. Though not the fanciest FCG out there(basically a mil-spec single stage), it functions fine.
    I would say go for it. You can always put that Geissele in another gun if it doesn't work, but I'm pretty sure it will.


    What you might try first, put a standard AR FCG in your RRA and see if that functions. If it does, you are GTG.
     

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    slsc98

    Ultimate Member
    May 24, 2012
    6,746
    Escaped MD-stan to WNC Smokies
    ...What you might try first, put a standard AR FCG in your RRA and see if that functions. If it does, you are GTG.

    Thanks outrider - that is clearer thinking than I was capable of late yesterday :innocent0 ; and, as luck would have it, after yesterday at the bench, there is quite literally a pile of oem AR FCG’s laying right next to my elbow!

    Gonna shoot skeet today and try to get this tonight or failing that definitely this week sometime and will report back. (Man it will be so sweet to get the heck rid of that stock RR FCG - it is THAT BAD! :mad54:

    Thanks AGAIN!!!!!!! :party29:
     

    outrider58

    Eats Bacon Raw
    MDS Supporter
    Jul 29, 2014
    49,818
    Thanks outrider - that is clearer thinking than I was capable of late yesterday :innocent0 ; and, as luck would have it, after yesterday at the bench, there is quite literally a pile of oem AR FCG’s laying right next to my elbow!

    Gonna shoot skeet today and try to get this tonight or failing that definitely this week sometime and will report back. (Man it will be so sweet to get the heck rid of that stock RR FCG - it is THAT BAD! :mad54:

    Thanks AGAIN!!!!!!! :party29:
    You got it! Have fun! :)
     

    slsc98

    Ultimate Member
    May 24, 2012
    6,746
    Escaped MD-stan to WNC Smokies
    Pulled the triggers and it almost wouldn’t surprise me if Rock River was getting their trigger parts FROM Palmetto State Armory!

    Rock River trigger assembly is the black metal with silver spring; and,
    Palmetto State Armory $49 “Enhanced Trigger Package” trigger assembly is the silver metal with black spring ...
     

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    slsc98

    Ultimate Member
    May 24, 2012
    6,746
    Escaped MD-stan to WNC Smokies
    BIIIIIIG difference in mass let alone geometry between the hammers though so, my wondering stopped here :-(

    Hammer assembly out of Rock River is on Right or Top palmetto state armory Standard AR hammer is on Left or Bottom ...
     

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    slsc98

    Ultimate Member
    May 24, 2012
    6,746
    Escaped MD-stan to WNC Smokies
    “Business” grooves ...

    Hammer out of Rock River is dark metal light color steel spring;

    Palmetto State Armory $49 “Enhanced” hammer is lighter color metal with dark color steel spring;
     

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    slsc98

    Ultimate Member
    May 24, 2012
    6,746
    Escaped MD-stan to WNC Smokies
    Sear surfaces ... crappy photos (dinner bell was being rung!)

    Hammer out of Rock River is dark metal light color steel spring;

    Palmetto State Armory $49 “Enhanced” hammer is lighter color metal with dark color steel spring;
     

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    slsc98

    Ultimate Member
    May 24, 2012
    6,746
    Escaped MD-stan to WNC Smokies
    Until I can find a replacement hammer (+/or polished trigger package) that is designed to replace the hammer in the LAR-40 (would appreciate any ideas on where I might find some!);

    Where I’m at is using ONLY the hammer in the Rock River LAR-40 that it left the factory with BUT

    seeing if swapping just the Palmetto State Armory trigger assembly in improves the trigger pull any.

    The Rock River stock trigger and hammer surfaces are SO BAD I wouldn’t even care if the “pull weight” stayed up around 7-8lbs (whatever it is, it is off the only trigger pull scale I have which is an old RCBS spring scale) - heck, if I could just get rid of the “wet sand” and terrible dragging id almost be willing to leave it as is ... luckily it is nothing more than a tin can killer and junk yard plinker ...

    (On second thought and in all seriousness, this pistol cal AR and the wife’s Colt 9mm AR do occasionally serve an important purpose and that is introduction and familiarization of frds and family who might be put off by the noise of the 556/223 variants. That and they are quiet enough to shoot in a lot of places where 556/223 would create much more of a “sound signature” and as a result nosey neighbors, etc.

    So, for those reasons alone my quest continues for a real nice, smooth and crisp break complete-package Fire Control Group I can drop into this Rock River LAR-40
     
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    outrider58

    Eats Bacon Raw
    MDS Supporter
    Jul 29, 2014
    49,818
    If you go to Geiselle's web site, they do NOT recommend using their trigger groups with PCCs. That's from my memory.
    I've got one in mine and it has been flawless.


    Personally, I think Geisseles are over priced. They're good, but from a person who has to scrimp and save for his gun money, a LaRue MBT-2S blows the SSA-E away. I have a couple of B-G2S-E from Brownells and they are a reasonable compromise for me.


    https://www.larue.com/products/larue-tactical-mbt-2s-trigger/


    https://www.brownells.com/rifle-parts/triggers-parts/triggers/ar-15-enhanced-triggers-prod67223.aspx?avs%7cManufacturer_1=GEISSELE%2bAUTOMATICS%2bLLC
     

    slsc98

    Ultimate Member
    May 24, 2012
    6,746
    Escaped MD-stan to WNC Smokies
    Coming back to update thread as I got through to Rock River Arms and they suggested Geiselle “offers something beefed up to handle the pcc bolts” but, follow-on pc with Geiselle dispelled that notion (but confirmed pcc blowback action does exert significantly more force, torque whatever on the FCG) Geiselle suggested I contact or check out ALG’s “ACT” . . . so, I started researching ALG’s “ACT” trigger and came across this 2018 thread on arc.com (the mention of damaged pin holes got my attention!)

    https://www.ar15.com/forums/AR-15/Trigger-slap-with-ALG-ACT-in-9mm-AR/66-731638/

    I had dropped just the trigger portion of the Palmetto State Armory into the RR LAR-40 (and left the OEM RR pcc hammer in) and there is a noticeable improvement in both reduction of pull weight (I really need to get a digital trigger pull scale!) AND ESPECIALLY reduced drag, “skipping,” and grittiness, etc.

    But, at this point, I am thinking as little as the .40cal AR gets shot these days I may just drop the OEM RockRiver trigger back in until I can determine if my .40 cal bolt is, in fact, ramped sufficiently, etc.

    And yeah, I need to get off the stick and order a couple of those LaRue triggers to try (I was told about them over a year ago so, no excuses for me)!
     

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