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Discussion Starter · #1 · (Edited)
I bought a 1966 336 RC in 35 Rem out of a pawn shop recently. It wasn't perfect by any means, but it wasn't too rough. After a week or so of removing a less-than-great camo paint job, and refinishing the wood, I took the gun out to the range for the first time. First shot, click, no fire. The primer was indented, but not properly. I loaded another shell. Another misfire, another shallow indentation of the primer.

I headed home. On the bench I observed that when I cycled the lever, I could still push the bolt forward with my thumbs even after the lever was fully closed. It wasn't much, maybe 1/32" or perhaps less. I had no actual way to accurately measure the amount, but every time I cycled the lever and closed the action, I could push the bolt further forward by a slight amount.

I had another curved grip lever from a 1974 336RC 30-30, so I tried it on the 35 Rem. When that lever was cycled and fully closed, the bolt was further forward. When I pushed on the bolt, I could feel movement, but it was extremely minor, much less than with the original lever.

I primed up a fired brass and tried it with the '74 lever. The primer fired. I tried three more and all fired. Back to the range, I ended up successfully firing 12 rounds, but I did have one shell misfire that I tried 3 times. (maybe a green box Remington issue?)

The conclusion is that the original lever isn't closing the bolt all the way, so the bolt is moving forward and absorbing some of the hammer energy when the hammer falls. Due to the bolt movement, the firing pin isn't hitting the primer hard enough. The lever from the '74 30-30 pretty much moves the bolt all the way against the breech, so the gun fires when the hammer falls. Seems I need some lever tuning, but I'm not for sure how that's done. I'm assuming a vice and some bending is involved. I'll do further searching for more info in posts, but would appreciate any advice from those with more specific knowledge of how this is done.
 

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Sounds like your original lever isn't pushing the locking bolt all the way up. The locking bolt is what sets the headspace. Lay the 2 levers one on top of the other and see where the discrepancies are...
 

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Or someone put a different locking bolt in and put one in that is too thin and your headspace isn't set right... And the tip of the new lever is pushing the bolt forward to the point it is able to fire... That however is not a good thing. The force of the round firing is supposed to be taken by the bolt and the locking bolt, not the tip of the lever...
 

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The original lever could be good, as Bart said, compare the two. Headspace is important and without gauges, the only way to check it is press a fired primer out a slight amount and close the bolt all the way. Measure the primer off the face with calipers to see what you have.
It's possible that you have some wear on the end of the lever, but the locking block is a possible culprit. The locking block is what really holds the bolt in the correct position for headspace.
 

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Discussion Starter · #5 ·
Lay the 2 levers one on top of the other and see where the discrepancies are...
I have done this and the most significant difference is the "point" (forward end of lever, toward the breech) of the original lever is slightly higher or more of an upward angle than the '74 lever. That's about the only difference I see, which is probably the one causing the bolt not to fully close against the breech.
 

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Discussion Starter · #6 ·
It's possible that you have some wear on the end of the lever, but the locking block is a possible culprit. The locking block is what really holds the bolt in the correct position for headspace.
Is the locking block the top protrusion on the lever just above the spring loaded plunger on the lever, or are you talking about something on the bolt?
 

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Discussion Starter · #11 · (Edited)
The adjustment is done with the locking bolt. They start with one that is too thick and thin it by filing until the headspace is correct...
Did a complete teardown this morning. The locking bolt shows some wear, but doesn't appear to be extreme. The locking bolt is not pinching / binding the rear firing pin. I placed a tiny washer, 0.050" thick on the flat area of the lever that pushes up on the locking bolt when the lever is closed. Then, I could pull up on the lever enough to pinch the rear firing pin enough that I couldn't push the pin forward, but I could still feel a slight movement when I pushed on the back end of the bolt. Seems I may have to replace the locking bolt.

Here are differences in the levers.
The original (won't fire) is on the top, locking hook on the left. The '74 model (will fire) is on the bottom, hook to right
Trigger Revolver


Here the original (won't fire) is in the back. The '74 model (will fire) is in the front.



Here the original (won't fire) is in the back, locking hook to right. '74 model (will fire) in the front, locking hook to left.
Machine tool



Here the original (won't fire) is on top, the '74 model (will fire) is on bottom
Belt Auto part Fashion accessory Strap Metal



Here the original (won't fire) is on top, '74 model (will fire) on bottom. Note on the '74 model, the flat area below the locking hook is larger and has a slight hump in it, appears it would raise the locking bolt higher into the notch in the bolt.
Bolt cutter Cutting tool Finger Strap Wire stripper
 

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These are some questions that occur to me that are not answered in the discussions above...

Are you saying that with the original lever, the hammer won't drop, or that with a round in the chamber, the hammer drops, but the round won't fire?

Can you push the bolt forward with a piece of brass in the chamber, or only with an empty chamber? In other words, is the extra bolt motion necessary to accommodate the thickness of the cartridge rim between the bolt face and the chamber?

Is it possible that the hammer spring was lightened by a previous owner? And does the firing pin with the hammer down protrude an appropriate amount? In other words, it has not broken nor been shortened? Has the firing pin been replaced for a one piece aftermarket one?

Are both finger levers depressing the tiny lever directly behind the trigger?

And then, will the bolt of the 336 fit and operate the rifle original to the other bolt?

It is very unusual for a finger lever or a bolt's articulating recess to wear so much that the rifle is inoperable. Can't imagine a rifle being shot that much. It would take tens of thousands of rounds. Just about everything inside the action would have to be sloppy loose. I'm suspecting that there is probably a simpler explanation.

If you absolutely determine that it is the bolt that is worn, it should be relatively easy to add a spot of weld to the articulating surface on the finger lever, and then file down the weld bead to fit. I'd try that before I replaced the bolt, the bolt lock, or the finger lever.

Let us know.
 
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Discussion Starter · #13 ·
Originally Posted by HIKayaker
These are some questions that occur to me that are not answered in the discussions above...

Are you saying that with the original lever, the hammer won't drop, or that with a round in the chamber, the hammer drops, but the round won't fire?

Hammer drops, round will not fire. Everything here is was done with factory Remington green box ammo.




Can you push the bolt forward with a piece of brass in the chamber, or only with an empty chamber? In other words, is the extra bolt motion necessary to accommodate the thickness of the cartridge rim between the bolt face and the chamber?

Either with or without a round chambered, and this is a 35 Rem, not a rimmed cartridge.




Is it possible that the hammer spring was lightened by a previous owner? And does the firing pin with the hammer down protrude an appropriate amount? In other words, it has not broken nor been shortened? Has the firing pin been replaced for a one piece aftermarket one?

I added a washer to the hammer strut to compress the spring a & add tension, but it didn't feel light. Firing pin is stock and appears to be OK, not modified.




Are both finger levers depressing the tiny lever directly behind the trigger?

Yes. The gun will operate the same with both levers with the single exception that the rounds will not fire with the original lever on the gun, but the rounds will fire with the lever from my 1974 336 30-30. The rounds that don't fire are struck, but the indention in the primer is apparently not deep enough to set off the primer.




And then, will the bolt of the 336 fit and operate the rifle original to the other bolt?

I have not tried the bolt from the 30-30 in the .35 nor have I tried the .35 bolt in the 30-30. I tried the lever because it is spare. I converted the 30-30 to a straight stock, and I had its old curved grip lever hanging on my pegboard, so I grabbed it and tried it.




It is very unusual for a finger lever or a bolt's articulating recess to wear so much that the rifle is inoperable. Can't imagine a rifle being shot that much. It would take tens of thousands of rounds. Just about everything inside the action would have to be sloppy loose. I'm suspecting that there is probably a simpler explanation.

If you absolutely determine that it is the bolt that is worn, it should be relatively easy to add a spot of weld to the articulating surface on the finger lever, and then file down the weld bead to fit. I'd try that before I replaced the bolt, the bolt lock, or the finger lever.

Let us know.


The gun will fire now with the lever from the '74 model 336. I fired 13 rounds yesterday, but one round would not fire. Today, after I tore down the gun, cleaned thoroughly, added a washer to the hammer strut, I pulled the bullet on the round and dropped the hammer on the primed hull 7 or 8 times. No fire. I pressed that primer out of the brass and pressed it in to a 6.5x55 brass, put that hull in my Tikal's T-3, and it fired. I pressed a new CCi 200 primer in the 35 R-P brass that would not fire, put that hull in the gun, and that primer fired first try.
 

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Discussion Starter · #16 ·
One more piece of info; the one shell out of the box that would not fire even after the spare lever was in the gun. I got out my headspace comparator bushing kit and checked the shoulder to base measurement of that one shell. It was 0.030" shorter from base to shoulder than any of the unfired shells left in the box or any brass that I fired in the gun. That explains why that shell wouldn't fire....
 

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Discussion Starter · #17 ·
I think I found the cause of the misfire, although I haven't fully tested the gun since applying the fix.

From all I could tell, the problem was the same as I originally described; when the lever was operated and returned to the closed position, the bolt was not fully forward against the breech. The bolt could be pushed forward even after the lever was fully closed. The amount of bolt movement was greater with the original lever than the spare lever, or the spare lever closed the bolt closer to the breech.

With info from this thread, I discovered the locking block and how it's tapered top helps close the bolt totally in the last few millimeters of bolt travel. By using a tiny washer on top of the bad lever, I found that I could get the bolt just as fully closed as I could with the good lever. That indicated the bad lever had some dimension that wasn't as it should be and had something to do with the height the locking bolt was lifted.

I took the bad lever to the vice and bent up the section of the lever that has the locking hook. That also moved the locking hook forward. Then, the locking hook on the lever hit against the locking hook on the locking block. I got the lever closed once and almost didn't get it open. I was able to slightly bend the locking hook on the lever back without making also go down. Now the bad lever closes the bolt as completely as the good lever, or maybe better.

As for the head spacing, it's fine as long as the bolt is fully closed, and not good at all if the bolt is not fully against the breech. Imagine a bolt action rifle where you could close the bolt before the face ring was against the breech, leaving a gap. That's much the same as what I had. I didn't do it, but I probably could have pushed the bolt forward with a shell in the chamber, then stuck a cleaning rod down the barrel and pushed the shell and the bolt back the same amount. Not good.

To the range Saturday.
 

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Or someone put a different locking bolt in and put one in that is too thin and your headspace isn't set right... And the tip of the new lever is pushing the bolt forward to the point it is able to fire... That however is not a good thing. The force of the round firing is supposed to be taken by the bolt and the locking bolt, not the tip of the lever...
Yes ----I would investigate the locking bolt----you are right ----that sets the headspace not the lever.
 

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Locking bolt not up far enough will also cause a misalignment of the two piece firing pin.
 
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