Marlin 336CS 35 Rem - shallow primer dent

[LuvMy1911]

Picked up a Marlin 336CS in 35 rem for my buddy to deer hunt with... it's no beauty, but bore looks good and it shoots straight.

Just one issue, it does not make a good solid firing pin dent on the primer and about 25-45% of the time the cartridge doesn't fire when this happens. Sometime it will if you try the same cartridge again.

I've taken a marlin completely apart to clean before (owner left it in the rain and it NEEDED it badly)

Should I;

A. Take it to a real gunsmith (almost none left in this area)
B. Measure some parts to determine if we need a new Main (Hammer) spring or a new set of firing pins (the 336 takes two I see). NOTE: to me, the hammer spring feels "weaker" on his 336CS than it does on my 1895SS.

Or, would you guys have any ideas on what to look for to pinpoint the likely cause of the problem???

Thanks in advance!

[No_1]

I believe you are on the right track by starting with a detailed cleaning. Once the rifle is apart you can visually inspect the firing mechanism (Spring, hammer, bolt, firing pins, ect). It should not be too difficult to determine if the firing pin assembly is the culprit or not. If it is not I would change out the hammer spring. Keep us posted with your progress.

[EMC45]

Factory loads or reloads? the .35 Remington is a stickler for headspace. If you adjust your dies too short it will misfire. I almost threw my Contender in the lake over this issue.......

[pietro]

.

I would also look beyond the two-piece firing pin, and inspect the FP recess/tunnel for chips/burrs/crud.

The MS can be shimmed with a washer @ it's back end, where the MS strut passes through the retainer under the rear tang, to give a bit more pressure, but that may also make it harder to manually cock and/or cycle.



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[Mk42gunner]

I would go with option B. Check the firing pin(s) and the recess in the bolt for burrs or peening.

Once you have it back together and it does the same thing, order a new mainspring.

Probable cause, amateur attempting to "fix the trigger" by cutting coils from the mainspring. Or it could just be weak and defective.

Robert

[LuvMy1911]

Thanks for the advice... The box that came with it looks like re-loads, also bought some new Rem.
1. Have cleaned it up quite a bit, no change
2. Removed the "cross-receiver" safety (looked like it was rubbing); firing pin dimple now seems deeper - and one of 5 unfired shells DID fire on a second try...
3. Added a washer under back of the main spring; dimple looks a little deeper now, still won't fire some of the cartridges that already have a dimple...
----- next steps to try -----
4. Firing pin (rear pin) appears too be kept in place with a roll pin thru the bolt? Is that correct? Next step is to disassemble the bolt and examine bolt and firing pins... Would anyone happen to know the correct lengths of either/both firing pins? (seems universal for many marlin lever guns)
5. Don't have headspace gauges or any place locally that does have them anymore... is there any "shade tree gunsmith" method of checking that?

[LuvMy1911]

..... Completely disassembled the bolt & cleaned Firing pins and FP tunnel, also stoned off a small burr on side of front pin. Neither firing pins seemed worn or battered. There was a lot of grainy rust & debris in/on pins and FP channel, cleaned with solvent, kroil, then lubed..... Hopefully that was the problem???

How much "play" should be in the bolt? If I push/pull forward and back (towards muzzle, then towards buttstock) I can see a very small amount of movement. Tried the same thing with my marlin 45-70 and it moves, but not as much... If the amount of movement is critical (It is, I think, affecting headspace?) please let me know how much movement is okay, and how much is not okay (I'll try to measure it tomorrow).

Too late to test tonight, will try tomorrow....

[Mk42gunner]

The modern 1895 is a 336 action with some mods for the larger cartridge. You could compare the firing pins, and even try the mainspring.

I checked the empty chamber bolt movement on the three 336's here. 1950 336A in .35 Rem none detectable. 1987 336CS in .35 Rem slight movement, I could feel it but not really see it, carbine has never misfired. 1993 30AW in .30-30 none detectable.

Robert

[texassako]

5. Don't have headspace gauges or any place locally that does have them anymore... is there any "shade tree gunsmith" method of checking that?

A shade tree method is to take a new, unfired case and add little pieces of tape to the case base until it will no longer chamber. Measure the stack. I have a shim washer assortment that made it a bit more precise than tape the last time I had to resort to this method.

[LuvMy1911]

A shade tree method is to take a new, unfired case and add little pieces of tape to the case base until it will no longer chamber. Measure the stack. I have a shim washer assortment that made it a bit more precise than tape the last time I had to resort to this method.

That sounds like a good way to get a good "reasonable" way to check headspace... I could also use some thin sheet metal would some shim stock work? I'll see what I have from 0.002 to 0.010 thick and see what happens?

Can anyone tell me what is and is a good or not good measurement for this method?

[john hayslip]

I've got a Marlin 336__ built in 1951 in 35 Remington and recently was having trouble with similar issues. I took the bolt apart, etc. I think the problem in my case was me. There is a piece of the lever that I don't remember the name of, that cams the rear firing up so it can strike the front firing pin. If the lever isn't all the way up you can have similar problems - there are times on mine it takes a bit of force to get it into proper position. Being extra careful to close the lever tightly has seemingly solved my problems.