Good evening all!  I have the opportunity to purchase a Rock River Arms LAR-15 #CM 014**.  Rifle appears to be like new, but has a firing problem.  Sequence is - chamber, fire, extract/eject, chamber, fail to fire (trigger won't work).  I manually chamber another round (rifle fires each time) then get a 3 round burst on the 5th try.  I have done the following test:  cock hammer (locks) and pull trigger (hammer releases)-hold trigger to rear and cock hammer (locks on disconnect)-slowly release trigger (hammer falls).  I have been in the military for 26 years, and am very familiar with the M16.  Upon inspecting the lower, I notice that the notch on the lower rear of the hammer appears to be a bad cast (notch isn't clean).  If I lightly stone out the notch, will this fix my problem, or am I way out in left field?  Thanks for all the help!     John    

If it was sold originally as a complete rifle, it has a lifetime warranty.  Easiest way to solve the problem would be to take the issue up with them, directly.  Their e-mail is [email protected].  I don't think anyone will be there to get it over the weekend, but they would get it first thing Monday.
Sluggo

You are probably on the right track.  When you hold down the trigger and charge it; it should cock and when you release the hammer the trigger isn't suppose to fall.  You just hear an audible click but the hammer stays cocked.  You said yours falls, so it failed that test.  The problem could be in the disconector or the hammer.



You might try that or maybe a new hammer and disconnector.

This is what I did.....removed the hammer, and carefully filed the bad cast in the notch.  I reassembled the rifle, and nothing had changed.  I then removed the pistol grip, safety, hammer, disconnect and trigger, inspecting each part.  I then put the whole thing back together, and guess what, it works!  I have been sitting here for half an hour doing the same test I described above, and have yet to have the hammer fall when releasing the trigger.  Hitting the range tomorrow.  Any ideas as to what the heck?  Thanks for all your help!     John

Well, back to square one.  Hammer is following the carrier home.  It works fine when I do the function check, but does the same as before when sending rounds down range.  What would be the most likely culprit?  Probably best to replace all lower guts?  Thanks for all the help!     John  

Sounds like a bad hammer.  Give Fulton Armory a call and they will fix you up.  I definately would not go to the range any more firing 3 round bursts!  That's the quickest way to lose your investment.  Sometimes cast parts are not to spec.  All is not lost, though.  Give Clint a call and he'll help you out!

DG

You are most likly correct on the fix, but if you arn't, you could blow your warrantee, SEND IT BACK TO RRA and have them do it and your safe.
Good Shootin, Jack

Sounds like the disconector is not properly engaging the hammer.  Could be bad hammer or bad disconector.  Change them both if you are in a hurry.  Otherwise, start with the disconector since they are less expensive.  

If you want to tinker...  try stoning a few thousandths off of the disconector on the forward nose that touches the trigger.  It will allow the disconector to rotate forward and increase the hammer engagement.

First, check to make sure the disconector spring has the wide end down or toward the trigger.  

Wow, lots of helpful info, thanks guys!  Turns out the rifle was built from a used parts kit, so no warranty.  I like to tinker, and have the time, so I think I'll go that route.  Parts seem to be fairly cheap, so if it screw it up, so sei es.  Range I use is pretty remote and everyone there is more helpful than paranoid, so I feel pretty safe.  Again, thanks for all the help, and I'll keep ya'll posted.     John  

Rather than just buying a disconector maybe get a lower parts kit and replace everything since you said it was built with a "used" parts kit.  Just a suggestion.  Give Georgia Precision a holler and Tommy will fix you up, he deals in RRA parts.

Remember that factory RRA guns have 2 stage triggers.  I have never worked on or taken apart a 2 stage AR trigger - it migth be different.  I say use the lifetime warranty.

D.

DD, rifle is made from a used parts kit.  How used, I don't know, so warranty is not an issue.  Except for the problem, everything looks good on the rifle.  I think a previous owner was playing games with a file, so I'm gonna replace all fire control parts just to be safe.  Beyond that, I'm gonna have to think real hard!

John

Bigballs: If the hammer is in specs, do as oldguy advised in the above post and that should correct the problem. Note: if all parts are in specs but receiver pin holes are not, your only recourse may be to do as oldguy advises. wots of luk, Jeep