Help needed on Marlin 20a pump .22

[poco loco]

My brother recently purchased a Marlin 20a pump .22 that was missing some internal parts.

We've figured out some of the problems and have installed new firing pin, ejector and are working on the cartridge guide assembly and the magazine.

Our problem is the schematics I have found are very difficult to see and figure out what else is missing.

I was hoping someone might be willing to either point to or post a readable schematic or maybe even take down their rifle and post a picture of the internals. This would be an immense help.

Also the magazine assembly has us stumped. We can't figure out how to install the spring and follower as there is a stud that mounts the tube and seems to block proper spring operation.

Thanks in advance for your help, we'd really love to put this sweet old piece of history back to fully operational condition. She does shoot well but without the magazine she's just not right. Thanks again in advance for your help..

 

[Jim K]

IIRC, that magazine is a conventional .22 tube type. The inner (brass) tube has a crimp at the back to hold in the follower, and a plug at the front which is turned and pulled out to remove the inner tube from the outer one. The plug is held in by a pin that goes through the tube and the plug. One end of the pin protrudes and acts to lock the inner magazine tube in place in the outer tube.

It sounds like someone took the spring, follower and plug out but then put the pin back in. To remove the pin, tap it out, then install the follower first, followed by the spring. If you don't have the plug, you will have to get one (try www.gunpartscorp.com).

If the above doesn't sound right, come back and I will try to get further info; that gun might be different.

Jim

 

[poco loco]

20a tube

actually this one's odd. The outer tube is the one that moves and the inner tube is fixed. There's a spring latch that holds the outer tube then when the outer tube is pulled up the loading gate is revealed.

That's what has me confused on assembly. I can't see how the spring mechanism can work let alone how it does.....

I'll try to get the camera to work and post a pic.

 

[poco loco]

pictures of tube and internals

 

[poco loco]

found the blowup, thanks dfariswheel

I thought I'd look at the page you linked for the 39m just for the heck of it. Lo an behold there was a 20a blowup at the site also so I think I can puzzle out what's still missing.

Still have no idea how to install the spring and follower. If anyone can help, I'd sure appreciate it.

I don't see how the assembly can work with the tube mounting stud in there. The stud is located about an inch from the top of the tube and it's about 3 inches above the loading gate. Being used to the normal tube type, this has me stumped. Probably very simple but I just can't visualize it....:banghead:

 

[poco loco]

Anyone out there know these rifles?

Found the diagram, still can't figure out the magazine assembly.

Any help would be appreciated, we had hoped to test her out this weekend....

 

[poco loco]

Anyone? last try at a bump then I'll try

TFL I guess. Anyone know of a site that might have info on this magazine assembly?

 

[RonnieT]

Poco,
if you have ever figured out how to make use of the mag spring, I would like to know.
I have had one for sometime now and someone disassembled it and I have it all back together but the mag spring.
the outer tube s almost junk , but I may can make it work with some massaging and solder but the pring and follower has me stumped?
The outer tube I feel must pull up on the follower some way to reset the spring?
prehaps the outer tube turns and locks when it is all the way up so one can load the new shells?
If you have yous fixed and have some pictures I would appreciate it.
thanks
Ron

 

[xtriggerman]

Just so happens I rebuilt a relic 20A for a guy last year. The Mag outer simply pulls the follower foward compressing the spring untill the follower passes the loading port for loading. Honestly, The original mags were the weekest part of the gun. The one I had had wore out the follower stop pin and the outer was just not able to hold the follower any more due to ware. Fix was to transplant a new 39 tube assembly on the 20A. I think I still have my spec sketch on the reciever/ tube addapter I made up. If you think you would like to go in this direction and put a end to the feeding problems once and for all, let me know and I'll dig up the specs and post it here. Iv got 3 of those pumps and enough parts to build 2 good ones out of the 3. Care full with the right side plate, nearly all the ones Iv seen are bent. They do bend back OK with TLC.

 

[RonnieT]

Yes I would appreciate anything you have that would help me fix the little .22
I have already prepared to go the "new route to the magazine.
by using the longest tube I could find and fasten it to the barrel by use of the Winchester type tube bands.
I feel like the most proble I will have is in the receiver
where the hole for the tube is , trying to enlarge it ?
I need an extrator and a couple springs also if you have anything please let me know.
Ron

 

[xtriggerman]

Here is the Marlin M39 magazine tube - reciever adapter specs. The finishing touches on the piece is to grind a radious relief on the side of the .490 diameter for the barrel. Just don't grind through to the inside. The outer mag tube fits very close to the barrel as it goes into the reciever. Basicaly, the small diameter end goes into the reciever tube hole and the mag goes into the larger end. The follower will need a little work so its length is matched to the action cartridge lifter. Once completed, the 20A is a sweet little action to shoot. As far as parts, one of these days when I get the 2 built with relined barrels each, Ill probably gun broker the left over stuff. Good Luck.

 

[z3marlin]

outer tube repairs

The outer tube on old marlin 22s has a 1/16" hole .140" from the back end of the outer tube, this hole when repaired by silver soldered for wear will pull a 1/16" pin that is pressed through the magazine follower. This pin in a longer length is also found holding the latch body into the front end of the outer tube.
Correct assembly follows: Straighten and lap fit- inner to outer tube with front plug removed. Check inner tube for slot clearance using 1/16" drill bit slide end to end. Clean both tubes and check for NO drag fit.
Follower with new pin ( shorten a numrich magazine latch pin ) The follower may have to be drilled at 90 degrees from original pin location to facilatate new pin installation. use variable cordless drill very slow, new 1/16 bit.
pin length from follower body is long enough to be pulled by outer tube when a trial fit reveals that the follower and pin can just be slipped into the back end of outer tube with NO inner tube present. Sliding the inner tube loaded with spring, with slot lined up front to the rear then captures the follower. Keep on sliding inner tube back out of the outer tube. When a 22 case can be placed perpindicular into loading slot, the assembly is ready for front latch plug assembly to be installed and pinned. Now the assembly is ready for installation. Extend outer tube another 1 1/2" then drop in screw through both outer and inner holes , when held in this position the assembly is slid into receiver and screw is tightened to barrel at dovetail threaded retainer. They do work!