The "Marlin jam..." - Bullcrap or true?

Chuck3436

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So I was googling accessories and the such for my 1894C, and I came across something called the "marlin jam."

Evidently the edge of the snail cam on the finger lever digs into the carrier and over time will cause double feeds.
The following link gives information...
http://marauder.homestead.com/files/marlin94fix.html


Now I've never heard of this issue before and various sources cite its either common or rare or its just straight internet sensationalism and this only happens to a few people who made a big deal of it on the net
.
Has anyone actually seen this happen, or have had this happen to them? If so, what round counts are we talking about? I believe there are people out there with marlins nearly a hundred years old that are still feeding and firing fine, so is this just one of those "I heard it on the internet," things like the 7.62x51 vs .308 trash floating around?

My pre-rem marlin functions absolutely flawlessly and feeds anything. I do see the little line on the carrier where the edge of teh snail cam hits it like in the pictures though. Just curious about this issue, and if its something I should address.
 
Yes, I've experienced this several times with the same rifle. The more vigorously you rack the lever, the faster it will show up. The top of the snail cam has a sharp radius, when you cycle the lever the shell lifter jumps and smacks back down on this "corner". over time a groove is forged into the under side of the lifter that the cam hooks up on. It can be smoothed out once or twice before you lose the timing and your gun starts to let two onto the lifter causing the lockup. I fixed mine permanently by inletting a piece of harder .020" feeler guage into the bottom of the lifter. If the gun is new, you can/should SLIGHTLY smooth out the radius on the cam itself, it will prevent the cam from forging a sharp groove,

I took pics and did a writeup on my adventures with my remlin 44 MAG. I'll see if I can dig the pics up for you, once it happens and you see where the issue is you understand how easy it is to fix.

EDIT; re round count, I have no idea. It started acting up well after the 500 round mark. I fed it a steady diet of 240 GR XTPs pushed by 23 grains of H110. not a light load.
 
Hmm, mine is still pretty minty, but its definately not 100% new. I know where to file, but I'm wary of fixing something that ain't broke!

If you have pics of your fix I'd be eager to see what you did. I found a pic of this guy putting a radius ont eh sharp edge...
http://rallred.smugmug.com/Other/Marlin-1894c-Jam/13264194_TQXrph#!i=964707402&k=Z5qDrGC




Yes, I've experienced this several times with the same rifle. The more vigorously you rack the lever, the faster it will show up. The top of the snail cam has a sharp radius, when you cycle the lever the shell lifter jumps and smacks back down on this "corner". over time a groove is forged into the under side of the lifter that the cam hooks up on. It can be smoothed out once or twice before you lose the timing and your gun starts to let two onto the lifter causing the lockup. I fixed mine permanently by inletting a piece of harder .020" feeler guage into the bottom of the lifter. If the gun is new, you can/should SLIGHTLY smooth out the radius on the cam itself, it will prevent the cam from forging a sharp groove,

I took pics and did a writeup on my adventures with my remlin 44 MAG. I'll see if I can dig the pics up for you, once it happens and you see where the issue is you understand how easy it is to fix.

EDIT; re round count, I have no idea. It started acting up well after the 500 round mark. I fed it a steady diet of 240 GR XTPs pushed by 23 grains of H110. not a light load.
 
I will look for pics as soon as I can, I'm at work tonight. In this pic from your link you can see the forged line from the cam, this is where I inlet-ed the feeler gauge. I filed an inlet and epoxied the strip of feeler gauge in there to give a harder bearing surface. After the mod, the issue never returned. You can see by the bluing loss how far the cam travels along the lifter. I ran my inlet the full length of the thin part.




I've dug some pics up here, but not what I'm looking for to show you. When I sold my Marlin, a sh!t ton of spare parts went with it including new finger lever and carrier. The first time it happened to me I just tossed new parts at it, the second time I decided to sort it out myself.

 
Well I went ahead and put the tiniest radius on that edge, basically just taking off the sharpness. In the pic here, http://marauder.homestead.com/files/marlin94fix.html#1
he barely takes anything off as well, just barely shaving off that edge. I checked the line to see if it had actually dug into the carrier at all, running a tiny flat head screwdriver along to see if the groove catches but it didn't, telling me that there was no appreciable wear to the carrier to worry about yet. Was worried that taking off too much would cause a timing issue and open a whole can of worms but I guess I lucked out.

In this pic http://rallred.smugmug.com/Other/Marlin-1894c-Jam/13264194_TQXrph#!i=964707402&k=Z5qDrGC he takes a CONSIDERABLE amount off that edge, which I'm sure would have caused carrier timing issues, which would require adding material to the carrier edge to set everything back to spec. I'm sure it would work, but didn't want to do all this for nothing, since everything was still pretty new and workign great anyways.

Lubed her up and cycled a bunch of snap caps as fast as I could and everything seems lickety split, so hopefully it prevents any issue in the future.
 
I bought one new, JM marked barrel, serial starting with 91, in 44 Magnum, and it jammed while feeding and extracting. I returned it same day and my money was refunded as this had apparently happened before.

The same thing happened to my friend's 444 Marlin, but being stubborn, he has tried to fix it but failed and now it stands by his front door.
 
I have a 44 mag jm stamp marlin that did this and was a such a pita. I purchased a new carrier and removed the sharp edge from the snail cam and its been ok since.
 
How much did you take off, and did you also do any modifications to the carrier?

I took a small amount, will take pic later. I did try and fix the original carrier with some jb weld but it would hold for 20 shots and the jb would fall off. I got the marlin from a cgn member who was kind enough to pay for the new carrier as he sold me the rifle as good working order.
 
Brownells sells a take-down thumb screw for the finger lever to replace the factory flathead screw. $10 very well spent.

I don't see these anymore, only the standard ones which are on backorder.

Grizzly customs has oversized fingers screws like I think you are talking about but they don't ship to Canada. Actually these guys have lots of neat stuff...too bad...
 
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I don't see these anymore, only the standard ones which are on backorder.

Grizzly customs has oversized fingers screws like I think you are talking about but they don't ship to Canada. Actually these guys have lots of neat stuff...too bad...


Your right, they don't list them for the 1894 any longer. Like this one for a 39a

ht tp://www.brownells.com/rifle-parts/receiver-amp-action-parts/receiver-hardware/receiver-screws/thumb-screw-prod8600.aspx
 
New XS iron sights and zero'd the scope today.

Only had the large aperature for the rear but managed 3" groups at 50 which I'm happy with considering the large aperature is humongous.
3.5-4" groups at 100 with the leuopold 2.5x scout scope.
All with factory 158grain CCI blazer SJHP.

Not bad considering I mounted and zero'd everything on the fly at the bench! Also first time out in nearly 6 months due to an excessively busy schedule. I don't claim to be an internet supersniper anyways. Everything fed smoothly and flawlessly after taking the edge off the cam for the jam fix.
 
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