M1 Carbine bolt won't lock back

[FireMedic102]

I posted about this over at the CMP, I got varying answers. Since I oiled my carbine the other day, the op rod will not stay locked open. I thought I over oiled so I cleaned it out, but the bolt still moves up and out. There feels like there is a little play with the op rod in the channel which I thought may be the issue, but I was also told this was normal with all carbines. The pin seems to be ok, so I am not sure that would be the issue. The other issue may be the groove where the pin goes, it may be worn out. Here is a pic, maybe other carbine owners can chime in. If the bolt won't lock open it really doesn't bother me, but it worked fine not 48 hours ago. The play in the op rod channel has me slightly concerned though if it is not in fact actually normal.

 

[Navy Moose]

There is a spring under the pin. It might be missing or worn. The slot looks ok to me.

 

[hminsky]

There is a spring under the pin. It might be missing or worn. The slot looks ok to me.

Yeah that is what happened to one of mine once.

 

[FireMedic102]

How would I check that? I am guessing the pin somehow pops out?

 

[Navy Moose]

How would I check that? I am guessing the pin somehow pops out?

The spring is called "Operating Slide Stop Spring" and the "Operating Slide Stop" holds it in place. This info is on p40 of the "M1 Carbine Owner's Guide" by Scott Duff. These are found on the side of the Operating Slide just above the handle on the Operating Slide below the plunger which you push down to lock the slide back.

The dis-assembly diagram for the locking mechanism is on the top of p85. The re-assembly diagram is on the top of p97.

Please note, I have not removed this spring before.

The link for the book is sold at Amazon.

 

[dhuze]

I have taken the spring out and the button on all my carbines. I can't recall how and I'm not home to look at it. I thing you need something small to push a little plunger in from the side then the spring and button come right out. It's more of a pain in the ass to put back together. with a little patiance you can get it pushed back in and released. It probably just needs some good cleaning.

 

[USMA-82]

I would guess the spring as well. Get it for $1.70 here:

http://www.e-gunparts.com/products_new.asp?CatID=11882

... or for $1.00 here:

http://www.amherst-depot.com/gunparts.carbine.htm

... or even $0.95 here:

http://www.fulton-armory.com/

Good Luck!

*

 

[George D]

Mine does the same thing. I guess I need a spring.

 

[Navy Moose]

If you're going to get a spring, order a complete spring kit. These war babies are getting along in years and a new set of springs might help problems from happening. Midway has it on backorder.