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View Full Version : Cannot pull back the charging handle....


GunPhonatic
10-15-2009, 6:51 PM
I just recently finished my 9mm AR build. I did a function test on it and the charging handle will not budge when trying to pull it back with or without a mag in there. I am using alot of force too when pulling.... I took out the bcg and charging handle from the upper(it slides fine in the upper) and inspected the lower. Nothing seems to be out of place. What would it be??

dchang0
10-15-2009, 7:02 PM
Ouch, sorry dude.

Well, test it in parts.

1) Disassemble rifle, insert charging handle only into upper, see if it slides freely in upper.

2) With upper still separate from lower, insert charging handle AND BCG and see if they operate properly.

3) Close up rifle with charging handle and BCG installed, no magazine, see if it operates properly (here's where you're likely to get stuck).

Take back apart and redo step #2, watching the bolt rotate into the barrel extension carefully, etc.

I'm sure you'll find something in doing those steps. If you're having trouble in step 3, my bet is on the magwell block getting in the way of the BCG somehow and preventing it from pulling back. If you're having trouble in step 2, it's probably the bolt failing to unlock from the barrel extension. If you're having trouble with step 1, it's an out of spec charging handle or gas tube.

Noobert
10-15-2009, 7:05 PM
see if your buffer tube is straight

GunPhonatic
10-15-2009, 7:08 PM
see if your buffer tube is straight

hmm never thought about that. Im gonna try that when i get home. thanks.

GunPhonatic
10-15-2009, 7:21 PM
Good info, thanks!

Ouch, sorry dude.

Well, test it in parts.

1) Disassemble rifle, insert charging handle only into upper, see if it slides freely in upper.

2) With upper still separate from lower, insert charging handle AND BCG and see if they operate properly.

3) Close up rifle with charging handle and BCG installed, no magazine, see if it operates properly (here's where you're likely to get stuck).

Take back apart and redo step #2, watching the bolt rotate into the barrel extension carefully, etc.

I'm sure you'll find something in doing those steps. If you're having trouble in step 3, my bet is on the magwell block getting in the way of the BCG somehow and preventing it from pulling back. If you're having trouble in step 2, it's probably the bolt failing to unlock from the barrel extension. If you're having trouble with step 1, it's an out of spec charging handle or gas tube.

Desert_AIP
10-15-2009, 9:09 PM
Ouch, sorry dude.

Well, test it in parts.

1) Disassemble rifle, insert charging handle only into upper, see if it slides freely in upper.

2) With upper still separate from lower, insert charging handle AND BCG and see if they operate properly.

3) Close up rifle with charging handle and BCG installed, no magazine, see if it operates properly (here's where you're likely to get stuck).

Take back apart and redo step #2, watching the bolt rotate into the barrel extension carefully, etc.

I'm sure you'll find something in doing those steps. If you're having trouble in step 3, my bet is on the magwell block getting in the way of the BCG somehow and preventing it from pulling back. If you're having trouble in step 2, it's probably the bolt failing to unlock from the barrel extension. If you're having trouble with step 1, it's an out of spec charging handle or gas tube.

9mm is blowback. No bolt lugs, no rotating, no gas tube.

To the OP
Do you have another lower to try it on to rule out a bent or misaligned receiver extension?

Which hammer are you using? A 9mm or no notch? Or does it have a notch in the top?

Is the ejector from the magblock catching on the bolt?

redcliff
10-15-2009, 9:14 PM
Do you have a notched hammer in your lower? They don't work with most Colt/RRA 9mm builds.

GunPhonatic
10-15-2009, 9:24 PM
9mm is blowback. No bolt lugs, no rotating, no gas tube.

To the OP
Do you have another lower to try it on to rule out a bent or misaligned receiver extension?

Which hammer are you using? A 9mm or no notch? Or does it have a notch in the top?

Is the ejector from the magblock catching on the bolt?

Yes I do have another lower I can try.Im using a 9mm hammer I got from Rainer Arms and the upper is from Spikes. Not sure if the ejector is catching the bolt...Ill have to check it.

Cyclepath
10-15-2009, 9:25 PM
Yes, a notched hammer in a non ramped Rock River 9mm bolt = bad news. You MAY need to punch out the hammer pin in order to separate the upper from the lower.

GunPhonatic
10-15-2009, 9:30 PM
Yes, a notched hammer in a non ramped Rock River 9mm bolt = bad news. You MAY need to punch out the hammer pin in order to separate the upper from the lower.

I can seperate the upper from the lower fine..I just cant pull the charging handle.

leelaw
10-15-2009, 9:59 PM
What kind of stock do you have on the rifle? Perhaps the inner diameter is too small for the bolt carrier.

69Mach1
10-15-2009, 10:46 PM
Are you using a rifle buffer?

luchador768
10-15-2009, 11:21 PM
These are by far my favorite type of threads on CalGuns! The number of people with vast gun knowledge, that are willing to help out a fellow shooter is so cool!


Good luck with the fix!
Peter

GunPhonatic
10-16-2009, 12:31 AM
Thanks for everyones help and input. It ended up being the HAMMER. I replaced the Rainer Arms 9mm hammer with a regular DPMS hammer from a LPK and it works perfectly now!

Desert_AIP
10-16-2009, 6:41 AM
Thanks for everyones help and input. It ended up being the HAMMER. I replaced the Rainer Arms 9mm hammer with a regular DPMS hammer from a LPK and it works perfectly now!

Interesting.
Never hear of problems with the 9mm hammers.
I wonder if RRA QC faltered a little during the recent madness.
Maybe the pin hole position was slightly off?

This one correct?
http://www.rainierarms.com//img/shop/product/ab13882103d0f7d818474c2cf217b58e.jpg

Dirtbiker
10-16-2009, 8:13 AM
Your 9mm hammer didn't work with your 9mm upper?? Weird.

The rounded DPMS hammers (I'm told) work fine in 9mm builds.

I was going to guess that maybe your magblock was set too high in the receiver.

GunPhonatic
10-16-2009, 10:17 AM
Yup it is that exact hammer pictured above. I guess it didd not work because it has a small notch in it and the DPMS one is fully rounded. The only way I found this out was because I had an extra lower that I am trying to sell that has a DPMS LPK installed.

evollep3
10-16-2009, 10:25 AM
great that you got your answer! cant wait to see it!

GunPhonatic
10-16-2009, 10:34 AM
Thanks, everyone on Calguns has been very helpful with my gun problems hehe. Well here is my thread with the pics

http://www.calguns.net/calgunforum/showthread.php?t=213507
great that you got your answer! cant wait to see it!

dchang0
10-16-2009, 12:26 PM
Glad you got it fixed! Sorry I forgot that it was a 9mm. My suggestions were a bit off...

Thanks for getting back to us too--it's always fun to figure these puzzles out.

Cyclepath
10-16-2009, 12:30 PM
Glad everything worked out. The 9mm AR is my favorite AR platform.

bm-bill
10-16-2009, 3:28 PM
You said it was a Spikes upper, did you get the bolt from Spikes also? If so it is a CMMG ramped bolt which will not work with the RRA hammer. You must use a regular non-notched hammer with a ramped bolt.

GunPhonatic
10-16-2009, 6:38 PM
You said it was a Spikes upper, did you get the bolt from Spikes also? If so it is a CMMG ramped bolt which will not work with the RRA hammer. You must use a regular non-notched hammer with a ramped bolt.


It was a spikes complete upper, so im sure it was a spikes bolt.

Cyclepath
10-16-2009, 6:43 PM
I believe Spikes uses a CMMG bolt in their uppers. They are working on manufacturing their own 9mm bolt but it has not been released yet.