Marlin 336C 35 Remington misfires

[fzgil]

I am having trouble with reloaded ammo in my Marlin lever gun. It fires factory ammo without a problem but my reloads (full length re sized) have been missing about 50% of the time. Primers are pushing back enough to be noticed. I think my die is setting the shoulder back allowing the firing pin to moved the cartridge forward. Second try sets off about every one of the misfires. I'm using Lee full length dies in a turret press. I had a gunsmith look the bolt over to be sure there were issues with the firing pins...
Any help appreciated

[smoked turkey]

This condition sounds like a classic headspace problem created by "oversizing" the brass during the FL sizing operation. I can speak with some authority on this because I have been guilty recently doing the same thing. I, probably like you have always screwed the FL sizing die down to the shellholder per instructions that come with the die. What I have been told by others more knowledgeable than me is to start with the die backed out at least a turn or two and gradually lower the die until you achieve full sizing of the case neck almost down to the shoulder. Stop a very little bit before you get to the shoulder. Try to see is the case will chamber in your rifle. If the case was one fired in that rifles chamber, chances are good it will chamber. If so, then finish loading up a few and give them a try. I think you will find the headspace problem to be taken care of. This is ofcourse a situation in which many other things could have contributed to the problem you mentioned, what I have suggested is a good place to start in your trying to figure out what the problem is.

[felix]

Follow the instructions as stated in the above post. No exceptions, written or otherwise. Also, check the headspace with purchased gages. My 336 gun barely closes on the field gage, meaning it has fired its share of hot loads. Use starting loads as max, once the cases are stretched out properly using sorta' hot loads. The problem is the small amount of metal on the case shoulder for maintaining the proper case length in the case body. ... felix

[357Mag]

FZ -

Howdy !

I have a M-336 XLR in .35 Rem.

IMHO......

FIrst off... you may not have to FL size. Both virgin .35 Rem brass and whole handfulls of brass fired in a M-336SC fit my rifles chamber w/o my having to FL size ANY of those cases. Those cases included a healthy dose of brass that had been fired with load development powder charges, that basically featured too high of chamber pressure. Again, this brass fit my XLR's chamber w/o FL sizing.

I don't use my XLR for hunting, but mostly for fun shooting @ paper targets.
Since I shoot reduce loads, again.... in my circumstance... I don't have to FL
re-size my fired brass; coming out of that gun.

Most .35 Rem reloading manual loads ( intended for Rem Model 8, Marlin M-336 etc ) are of moderate enough pressure that FL sizing might prove unecessary, after such loads are shot in your rifle ?

You can use something like a .380 ACP sizng die as just a .35 necksize die.
Also, the approach chamfer @ the bottom mouth of the .380 ACP die can be impressed into service to do a "shoulder bump" of your .35 Rem brass.
So... you could do both processes w/ one (non -custom ) die.

In theory... with a correct load of correct pressure, you might be able to simply neck size & shoulder bump your .35 Rem's. And... if the load allows, even the
shoulder bump might not have to be performed for a few firings.

You'll likely have to bump the shoulders ( when required ) just a scant .001" or so.

With regards,
357Mag

[fzgil]

This condition sounds like a classic headspace problem created by "oversizing" the brass during the FL sizing operation. I can speak with some authority on this because I have been guilty recently doing the same thing. I, probably like you have always screwed the FL sizing die down to the shellholder per instructions that come with the die. What I have been told by others more knowledgeable than me is to start with the die backed out at least a turn or two and gradually lower the die until you achieve full sizing of the case neck almost down to the shoulder. Stop a very little bit before you get to the shoulder. Try to see is the case will chamber in your rifle. If the case was one fired in that rifles chamber, chances are good it will chamber. If so, then finish loading up a few and give them a try. I think you will find the headspace problem to be taken care of. This is ofcourse a situation in which many other things could have contributed to the problem you mentioned, what I have suggested is a good place to start in your trying to figure out what the problem is.

Smoked Turkey,
I was following the Die instructions as noted above and understand your process well enough to move forward with some once fired cases.
I do have 100 or so brass from the loads that were misfires, some of which were loaded a number of times @ FL resizing. Will loading these in the same manner allow them to stretch back out or will I need to fire form these?
I really appreciate the help BTW!
Frank

[smoked turkey]

Frank what I understand is that your cases misfired but they did eventually work in your rifle after a try or two. Based on my experience, your cases are fireformed to your chamber now that they have been fired. In any event what I would do is neck size them as explained. I would then drop the fired and neck sized cases in the chamber to see if they drop in ok. I think they will. If so then proceed to load as normal. I am real careful in the seating, crimping process that I do not set the case shoulder back by excessive crimping. So I'd recommend light crimp only. I usually push down on the boolit with my thumb pretty hard to insure they are tight in the case neck. That tells me the crimp is ok. With that said I will say that you may still have some of your cases misfire due to the original shoulder set back, but I am betting that most of your loads will fire ok. I should say that since you mentioned your cases had been fired several times, so I would check for overall length and trim them to specifications if needed before loading. There are many experts here that may have some additional insight for this problem. I think you are on the right track to solve most of your misfire problems.

[fzgil]

Thanks for the response smoked turkey. I will be more vigilant with the crimp process as well as the resizing die depth on my next batch of boolits.
Thank You again
Frank

[Rico1950]

Had a similar problem with the TC Contender. Lube your decapping pin before you run it into your case. You'd be surprised how much headspace changes when you run an unlubed decapping pin into a 35 Remington case.

[fzgil]

Had a similar problem with the TC Contender. Lube your decapping pin before you run it into your case. You'd be surprised how much headspace changes when you run an unlubed decapping pin into a 35 Remington case.

Now I'm confused...(doesn't take much)
How can the decapping pin affect headspace?

[uscra112]

He means the expander ball on the decapping pin, I think. Although I can't see that happening, since the ball enters the case while the neck is still expanded and should not even contact the neck, much less compress the case and push the shoulder back.

[smoked turkey]

When you pull the expander ball back out of the sized neck it is supposed to expand it to the proper diameter on the "inside" for the new bullet or boolit. This does sometimes take quite a bit of force to pull the expander ball back through the newly formed case. I think this is what is being referred to in the above post. Although it seems to me this would pull the shoulder and could make the newly formed case harder to chamber. To alleviate that I sometimes lightly lube the inside of the neck with a Q-tip and a very little bit of sizing lube. You really have to clean the inside of the neck if you do this to avoid any problems with the lube inside the case. I usually run patches through the newly sized cases to clean off the lube and then as a last step before loading I always run the batch through the viberator cleaner to make sure all lube is gone. This is my procedure. I'm sure others have their own take on it.

[geargnasher]

He means the expander ball on the decapping pin, I think. Although I can't see that happening, since the ball enters the case while the neck is still expanded and should not even contact the neck, much less compress the case and push the shoulder back.

My RCBS FL sizing die does stretch cases, but I don't see how it could compress them, either. There is such a huge difference between the diameter of the neck sizer and the expander ball that it really works the brass hard, and requires some force to pull back through the neck even when the inside of the neck is lubed. This excessive force can and will drag the shoulder out a few thousandths. I've resized brass that was 060" too long when reforming '06 brass, and the RCBS die swallowed it no problem. I don't have any idea if the Lee FL dies would do the same, though, if the brass was too long.

Frank: My advise would be to follow the advise given about backing off your FL die, and when you load your next batch, seat the boolits out far enough to engrave in the rifling and offer some resistance to closing the lever the last little bit. You might not be able to utilize the crimp groove for this, and if not, just single-load them and don't bother crimping. What this does is force the case head firmly against the bolt face and gives the firing pin something to act against, in this case the boolit in the throat rather than the shoulder like it should, but can't, because the shoulder is too short. When fired, the shoulder will blow forward to form to the chamber rather than the whole case moving forward when the firing pin hits it, expanding to grip the chamber when it goes off, and stretching back near the case head causing exessive wear and tear on the brass and accelerating incipient case head separation.

Once you shoot all of them once this way, invest in a Lee Collet neck sizer die and only size the neck until you have difficulty chambering them again, then only bump the neck a thousandth or two in the FL die, and if I were you, I'd do my neck bumping with the expander ball removed and let the Lee Collet mandrel do the expanding on the UP stroke when you reload them. This will keep the shoulders from being stretched.

Gear

[fzgil]

OK now I get it...I'll be loading a batch this weekend and will probably try them on Monday. I truly appreciate all the input. This is a great site!
Frank

[Dthunter]

Try dipping your case necks into a small container filled with #7-1/2 shot and some dry grafite powder.
Less clean up= less hassel and more convienience. No potential for contaminating the case powder chamber with lube.
Good luck and have fun!