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1/5/2014 1:00:44 PM EDT
I am having issues with my CMMG dedicated upper on a pre ban lower with Magpul CTR stock.  When it's freshly cleaned and oiled it runs ok, but dry it seems it's having a hard time reseting the trigger.  Should I use a lighter hammer spring?  Does is still need break in?  I have less than 100rds through it.  Does anyone else have an issue like this?
I want this to run like my CMMG dedicated 9mm post ban..  That gun is amazing..

The lower is a pre 94 PWA in mint condition.  I changed out the buffer tube/spring/buffer to milspec to use a CTR Mil Spec.  Everything else is pre 94 in MINT shape.
1/5/2014 1:20:20 PM EDT
[#1]
Um, re-lube it?  And keep shooting, it may need a bit more break-in period. Dont run it dry... it causes unwarranted wear.
1/5/2014 1:20:56 PM EDT
[#2]
Hey "Z", we used to live in CT on Bradley Lane, just off RT34 in Sandy Hook
but moved a year before the insanity. I bought my first AR22 from K5 Arms
in Milford. Moved down here for a better life...but to your question.

100 Rounds of what? Some .22 cartridges are a bit weak on power and will
not provide enough recoil to reset the hammer. As far as break-in is concerned,
the CMMG barrels really don't require a high round count to bring in accuracy,
however, their chambers tend to be a bit rough and can stand a "buzz" to smooth
them out. But that usually isn't a cause of reset issues.

Before you try cutting coils off the recoil spring try running nigh velocity - NOT
hyper velocity - ammo and see if it improves. If you start seeing reset more
frequently then you are headed in the right direction and a higher round count
will most likely cure the issue. I wouldn't alter the hammer spring until you've
done the HV ammo thing. Then if things haven't improved try cutting off two coils
from the recoil spring, test, then if no results, two more. No more than 6 total and
before you do, order CMMG's 22ARC Survival Spring Kit. That way you can always
get back to original condition.

There are other causes but with the gun this new I think some "tincture of time"
is the best medicine.

Ted
1/5/2014 2:54:24 PM EDT
[#3]
AFSC2W171Z we probably ran into each other.  I worked when I first moved to CT in 97 at 21 years old at the gun store in shelton (I know the owner has his issues) and did some work/computer work at Sportsmen's outpost in Wolcott (Mike is a GREAT GUY). My primary thing is IT and worked for People's bank, Unilever and Sikorsky aircraft.  Glad to see you got out without giving up a leg or collection.  

Back to the issue at hand, I did lube the hell out of it 3 times in 100rds.  I use high/Hyper vel ammo and have absolutely no faith in the gun.  I want and if SHTF, need to depend on it. Even my parents who have never worried about things like the economy failing are talking "what if"....
1/5/2014 3:43:57 PM EDT
[#4]
Quote History
Quoted:
AFSC2W171Z we probably ran into each other.  I worked when I first moved to CT in 97 at 21 years old at the gun store in shelton (I know the owner has his issues) and did some work/computer work at Sportsmen's outpost in Wolcott (Mike is a GREAT GUY). My primary thing is IT and worked for People's bank, Unilever and Sikorsky aircraft.  Glad to see you got out without giving up a leg or collection.  

Back to the issue at hand, I did lube the hell out of it 3 times in 100rds.  I use high/Hyper vel ammo and have absolutely no faith in the gun.  I want and if SHTF, need to depend on it. Even my parents who have never worried about things like the economy failing are talking "what if"....
View Quote


Yep bought from Shelton guy once or twice before he had his troubles. Was
Senior Project Illustrator for Sikorsky (29 years), so we probably did run in to
each other from time to time.

Please don't shoot the hyper velocity stuff, CMMG uses a sporting chamber and
while looser than a match chamber you'll be better off staying away from the hyper.

Try cutting the coils and see where that takes you. I'm usually here for further advice
and there are a whole cadre of other experts like Dave South, Dave North, and John
in TN. Also, buzz the chamber. Keep us informed, worse comes to worse call CMMG CS.

Ted
1/5/2014 5:32:37 PM EDT
[#5]
Quote History
Quoted:
Hey "Z", we used to live in CT on Bradley Lane, just off RT34 in Sandy Hook
but moved a year before the insanity. I bought my first AR22 from K5 Arms
in Milford. Moved down here for a better life...but to your question.

100 Rounds of what? Some .22 cartridges are a bit weak on power and will
not provide enough recoil to reset the hammer. As far as break-in is concerned,
the CMMG barrels really don't require a high round count to bring in accuracy,
however, their chambers tend to be a bit rough and can stand a "buzz" to smooth
them out. But that usually isn't a cause of reset issues.

Before you try cutting coils off the recoil spring try running nigh velocity - NOT
hyper velocity - ammo and see if it improves. If you start seeing reset more
frequently then you are headed in the right direction and a higher round count
will most likely cure the issue. I wouldn't alter the hammer spring until you've
done the HV ammo thing. Then if things haven't improved try cutting off two coils
from the recoil spring, test, then if no results, two more. No more than 6 total and
before you do, order CMMG's 22ARC Survival Spring Kit. That way you can always
get back to original condition.

There are other causes but with the gun this new I think some "tincture of time"
is the best medicine.

Ted
View Quote

If the chamber is rough the spent brass sticks in the chamber and robs some of the energy the bolt needs to cycle,
A little buzz in the chamber will allow the brass to eject easier and with more energy for the bolt to cycle.
I would buzz the chamber before trying other mods.
1/5/2014 6:19:00 PM EDT
[#6]
Beat me to it Red
1/6/2014 4:16:24 AM EDT
[#7]
Your question has pretty well been covered.
Keep shooting after you try some of the suggestions.
Everything will work fine after that and a few hundred
more rounds unless you have an unusually strong Hammer
Spring or are using sub ammo.

Dave S
1/6/2014 7:57:31 AM EDT
[#8]
Sub ammo sounds like a pipe dream.  I will try the other suggestions and let everyone know.
1/6/2014 8:37:52 AM EDT
[#9]
Quote History
Quoted:
Sub ammo sounds like a pipe dream.  I will try the other suggestions and let everyone know.
View Quote

Break it in with several hundred rounds of high velocity amo then give subsonic ammo I try.
1/6/2014 8:44:20 AM EDT
[#10]
Buzz the chamber really well with a chamber brush, some clp and an electric drill on low.

Get the taccom reliability kit if you haven't already. the pressure plug helps keep the 22 bcg up against the barrel collar and stops you from losing any valuable inertia.

Try running it dry. I know a poster said it causes too much "wear" but I haven't seen anything drastic on my gun after 1000's of rounds running it dry. I also tried to lube mine up when i first got it thinking it played by typical AR rules until a poster suggested I stop lubing it. The dirty chamber of the .22 gunks up really really quickly when there's lube present.

Try to stick to copper plated high velocity stuff. That's what cmmg recommends and what i've had best results with.
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