Marlin 336 jamming - advice?

[Len_in_Phoenix]

Hello all

I took the plunge earlier this week and purchased my first lever action rifle....a Marlin 336 in .30-30. According to the serial number lookup webpage, my gun was made in early 1960.

Here's my problem: Once in a while, the last round I loaded (closest to the action in the magazine tube) will only partially move from the magazine onto the carrier/lifter/elevator - whatever you call the thing that lifts the incoming round from the magazine to where the bolt can push it forward into the chamber. The incoming round sticks tightly enough that a couple of my test rounds are actually dented. When it does this, I have to reach in through the ejection port with a screwdriver to force the round onto the lifter, leaving a huge scratch on the shell casing where it has dragged past the edge of the magazine tube.

If I push the round farther into the magazine tube when I load it and let it spring back to the "rest" position the jam doesn't happen. It only happens when the round is slipped into the loading port just far enough for the gate to close. When I push the round farther into the magazine it doesn't actually stay farther forward...it still springs back to what appears to the the same rest position.

Is this operator error during the loading sequence on my part? Or do I need to replace some worn parts? After 44 years of people playing Rooster Cogburn with it, I wouldn't be surprised if the rifle was a bit out of spec. I got a good deal on it, so spending some money to make it right doesn't bother me.

Any advice would be appreciated. I still haven't shot it yet, but I'm planning to this weekend. I'll report on how it works next week.

TIA

Len in Phoenix

 

[KaceCoyote]

Well though I cant say with complete confidence here, but I think I know your problem.

It sounds to me like a feeding tube issue but I could be wrong. Firstoff try to open up your magazine tube. Clean the inside of that tube as completely as possible, gook from over the years may've gathered in there. Chuck the spring and replace it, I know the plastic followers slide along the tube alittle smoother so that might be a good idea.

How hard/fast are you working that lever? You need to give that thing a real good flick.

 

[George Hill]

Is the next round in the magazine pushing against the cartridge at all?
Are you "Short Stroking" the lever?

 

[Len_in_Phoenix]

Hi again

Thanks for the replies. I just spent some more time working with the gun, and I've now figured out how to reproduce the problem at will.

First of all, let me clarify something: When I said the shell was getting stuck coming out of the magazine, I meant STUCK!! I've attached a picture of my test round to show how badly scarred up the case is after my experimentation.

Here's what I've figured out......

A) Magazine tube and spring. The magazine tube is clear and free of obstructions. The magazine spring has plenty of tension on it. When the shells don't jam and actually clear the magazine, they hit the back of the receiver with a solid whack. I do have a replacement spring on order from Midway, though. After 44 years, it's time for a new one just on gp.

B) Short stroking and working the action with "vigor" - Working the action "fast and hard" actually makes the problem worse. If I go slowly, everything is just fine.

C) THE ISSUE: While I was comparing fast vs. slow lever flicks, I watched through the ejection port to see exactly what the lifter (carrier? elevator? I'm still not sure what to call the thing) was doing. The motion of the lifter can best be described as matching a capital J. It reaches the low point of it's travel BEFORE the end of the lever stroke and THEN STARTS MOVING UP WHILE THE LEVER IS STILL MOVING OUT AND DOWN. The timing of the upward motion begins as the bolt is just clearing the ejector on the opening stroke. If you have a 336 handy, work the action slowly and you'll be able to feel a slight pulse when the spring loaded ejector clears the bolt on the opening stroke. This is when the lifter begins it's upward movement on my rifle. If I work the action slowly, the incoming shell will pop out of the magazine and onto the lifter perfectly while the lever is still on the down/opening stroke. After that, everything works fine. If I work the action 'fast and hard', the upward movement of the lifter begins as the incoming shell is only partially clear of the magazine and it sandwiches the shell between the lifter and the magazine tube, causing the jam and requiring a screwdriver to pry the shell out from between the magazine and the lifter.

My next step is going to be to completely disassemble the rifle and check the bearing surfaces inside. I don't have the proper screwdriver to remove the carrier screw, and I'm not in so much of a hurry that I'm willing to bugger up a screw head just to check a theory, so it will have to wait until tomorrow. Here's my thought: Is the lifter actuated by a cam? Perhaps on the lever? If so, I'm wondering if the bearing surfaces are worn to the point that the cam surface has gotten small enough to effectively change the timing of the components in relation to each other. I don't think it's worn un-evenly, because the J pattern of movement doesn't repeat itself in reverse on the lever-closing stroke.....the lifter just continues it's upward motion.

I'm not a gunsmith and this is the first lever action rifle I've ever played with. This is just a theory based on observation and how I think it should work. Does is sound plausible? Or am I way off base?

Now the big questions: If I'm right and it's worn enough that the timing has changed, how critical are the tolerances for replacement parts? Are these drop in parts or am I about to learn how to fit parts in a lever gun? Any suggestions on finding the best price for replacement parts?


As always, I appreciate the help.


Len in Phoenix

 

[Wildalaska]

Your rifle is out of time, carrier dog is probabaly wore...gunsmith time.....

WildbutitsaneasyfixAlaska

 

[George Hill]

To have a gunsmith do it, might cost a lot... it might by cost effective to send the rifle back to Marlin and have them do it.
http://www.marlinfirearms.com/repairs/index.php Only 35 bucks for them to do it plus parts.
*shruggs*

(I say this because the last gunsmith I had look at a Marlin .44 mag he wanted 85... a guy in Virginia in near Roanoke)

 

[Bullet]

I'm not sure if this will help you but try this web page.

http://marauder13.homestead.com/files/marlin94fix.html

 

[dogngun]

I had an old model 36 (pre-336) that did the same thing. I replaced the magazine tube spring and follower and cleaned the magazine tube out with Hoppe's and it worked fine.

I agree that this might be something you might want to send back to Marlin, just describe the problem to them exactly.

Good luck

Mark

 

[Len_in_Phoenix]

Hello again

KaceCoyote and dogngun win the prize. I was planning to take the rifle to my 'smith on Monday, but last night I decided to put in the new magazine spring I received in my last Midway order just to see what it would do.

I removed the magazine end cap carefully, expecting it to pop off and go flying........NOT. The old spring barely even reached the cap. I had to dig in the magazine tube with a hooked probe to get the old spring out. I trimmed the new Wolffe spring so that it was 4" longer than the one I took out (I know that it may be too long, but it's easier to shorten it again than to make it grow) and installed it.

It works! Every time! Fast or slow!

My thanks to everyone who responded. I took it to the range today and it rewarded me by putting 5 170 grain soft points into a group just a hair under 1 1/8" at 100 yards.

Another happy gun.

Len in Phoenix

 

[JohnKSa]

My thanks to everyone who responded. I took it to the range today and it rewarded me by putting 5 170 grain soft points into a group just a hair under 1 1/8" at 100 yards.

A 40 year old lever gun that shoots close to MOA. You got a good one, for sure, but that kind of accuracy from a lever gun is not as surprising as some folks seem to think.

 

[Lone Star]

Let's sum up; I got a little confused.

Are you saying that the old magazine spring was short and weak, and that putting in a replacement spring solved the problem?

Does anyone know about how long the original spring lasts in modern M336's?

Lone Star