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kenjuudo
03-25-2005, 06:12 PM
Went into a pawn shop to pick up some movies, they hawk them for $2. On the rack was a Marlin 30-30 with the sticker still on the forestock, no wear at all, bolt ,lever, anywhere. Action hasn't been cycled enough to wear the blueing on the hammer. A half hour of haggling and a declaration of my dubious ancestry put it in the truck for $200.

The bore has a .0025" consriction at the threads, I'm thinking I'll run a couple of boxes of factory through it, cleaning between at the appropriate times then fire lap if necessary, this sound reasonable?

Anyone know where I can get instructions for disassembling the action on this critter, it's the first lever action that ever followed me home?

Scrounger
03-25-2005, 07:05 PM
Went into a pawn shop to pick up some movies, they hawk them for $2. On the rack was a Marlin 30-30 with the sticker still on the forestock, no wear at all, bolt ,lever, anywhere. Action hasn't been cycled enough to wear the blueing on the hammer. A half hour of haggling and a declaration of my dubious ancestry put it in the truck for $200.

The bore has a .0025" consriction at the threads, I'm thinking I'll run a couple of boxes of factory through it, cleaning between at the appropriate times then fire lap if necessary, this sound reasonable?

Anyone know where I can get instructions for disassembling the action on this critter, it's the first lever action that ever followed me home?
I copied this from the 'net:
TUNING MARLIN LEVER ACTIONS

By Lionel Roach, aka JONAH

Update: 9/27/02

Editorial note: This is information only about what a few cowboys found worked for them. If you do not feel comfortable working on your gun and assuming liability, please go to a good gunsmith and let them tune your gun.


Those involved in Cowboy Action Shooting (CAS) have never had it so good when it comes to firearms and related equipment. While some manufacturers were slow to climb aboard the bandwagon, others listened to what shooters wanted and responded. Marlin Firearms worked with shooters and gave us the Model 1894 and the Model 1895. An informal count of the number of Marlin Model 1894's at any CAS shoot will show how popular the Marlin has become. At shoots that I've attended, at least fifty to sixty percent of the rifles being used will be Marlins.

A sideline industry has emerged to tune and modify the firearms used in CAS, but individual owners can perform many of the tune up procedures themselves. There are some parts that are best left to the professionals or at least advanced amateurs such as working on sears and hammer notches. However, with a little bit of time and minor tools, the average owner can do a good job of smoothing up their action.

The following procedures apply to the Models 1894, 1895 and the 336. For additional instructions covering lever action rifles, Accurizing The Factory Rifle, by M. L. McPherson, is the best book I have read and I highly recommend it.

TOOLS AND EQUIPMENT

Before you attempt to do any work on your rifle, get a good set of gunsmith screwdrivers. Do not try to use your hardware store special screwdrivers. Burred screw heads will result from use of standard screwdrivers. Gunsmith screwdrivers are available from Lyman, Chapman and others. If not available locally, gunsmith screwdrivers can be ordered from Midway, Brownell's and others.

Additional equipment required will consist of a sheet each of 400 and 600 grit wet or dry paper. Nice to have would be a few small hones, but the wet or dry paper will get you by. When we begin to work on the hammer, a belt sander or bench grinder will be required for part of the procedure.

INSPECTION

Before beginning with the actual tune up, cycle the action slowly and try to determine where in the cycle roughness is felt. The areas to pay attention to are the lever plunger that holds the lever closed, the carrier lifting up, the bolt sliding in the receiver and the bolt passing over the hammer. All of these areas will most likely require attention and will be addressed during the tune up. Unless you have been shooting your rifle a great deal, I recommend that you cycle the lever several hundred times prior to beginning any work. This will accomplish two things. First, it may smooth out any burrs that are there. Second, it will leave burnish marks on the areas that are in contact so you can identify those areas needing work. If you reload, make up several dummy rounds, without primer. Cycle these dummy rounds through the action. By doing so, you may find areas inside the action where brass has rubbed off on the parts. This will give you an excellent idea of where to spend time polishing those parts. Before disassembly, slowly open the action and observe the point at which the hammer comes to full cock. On my Marlin 1894 and 1895, the bolt depressed the hammer another 3/32" after reaching full cock. I have observed the same amount of over travel on other Marlins. We will address this when we work on the hammer.

DISSASEMBLY

Begin disassembly by opening the action about half way and remove the lever screw, the lever, the bolt and the ejector. Remove the rear tang screw and slide the stock of the rear off the action. Lower the hammer by depressing the trigger safety block. Hold the hammer under the thumb, depress the trigger and let the hammer go forward against the frame. Remove the hammer spring by sliding the hammer spring plate to the left side and then remove the hammer spring. Remove the hammer pivot screw and remove the hammer through the clearance slot by rotating it upward. Turn the rifle over and remove the trigger guard plate support screw from the left side of the action. Then remove the trigger guard plate screw from the bottom. This is the screw just in front of the carrier leg slot. Note that this screw is longer than the previous screw. Lift up on the lower tang and remove the trigger guard plate. Remove the locking bolt from the bottom of the action. Remove the carrier screw from the right side of the action. The carrier will now fall out of the bottom of the action. There is no need to remove the loading gate screw. The action is now dissembled as far as required for the tune up.

LEVER

Inspect the lever for any burrs on the end where it bears on the carrier and bolt. Burnish marks on the end will show where it is in contact with the carrier and bolt. Lay a 2" by 2" piece of 400 grit wet or dry paper on a flat surface near the edge of your workbench. Place one side of the lever flat on the paper and polish the side. Then flip it over and polish the other side. Polish off any burrs found on the two narrow edges. Stay clear of any of the areas that will be outside of the action so that you don't remove any bluing. This is a polish only operation. Do not remove metal or change the shape of the end of the lever.

Editor's note: Also refer to the Marlin 94 Fix. It describes a fix for preventing a timing problem due to wear of the excellent Marlin action. Fixing the Marlin JAM

The finger lever plunger will need to be polished and the spring tension reduced. With a small punch or nail with the end ground flat, remove the plunger pin. The plunger is under tension, so be careful and don't let the plunger and spring jump out and get lost. Hold a finger over the plunger end or put a small rag over it to contain it. Using the 400 and 600-grit paper, polish the two bevels on the end of the plunger. Check the shank of the plunger and remove any burrs you may find. Place the spring back on the plunger and insert it into the hole in the lever. While looking through the pin hole, push the plunger in until the hole is clear. Continue pushing in the plunger until it is flush or nearly so. This will give you a good idea of the amount of the spring that can be removed. In my rifles, I removed two coils by cutting them off with a good pair of side cutters. I recommend that you only cut one coil at a time and then try the plunger in the lever for tension. The plunger must have enough tension to fully extend and lock the lever in the closed position. If you remove too much of the spring, you may find that the lever will unlock when you fire the rifle with heavy recoiling loads. Since your fingers are through the lever when firing, this is not a dangerous occurrence. However, it is annoying.

TRIGGER GUARD ASSEMBLY

Unless you are experienced in working on sear surfaces, I recommend that you leave the trigger and sear alone.

Take the trigger plate in your hand and look down into it from the top side. You will see the trigger block safety spring. This spring also bears on the rear of the trigger. Using a small screwdriver under the short leg, the one bearing on top of the trigger safety block, pry up on the spring approximately 1/8". You want to bend this leg upward enough to relieve tension on the trigger safety block. Don't try to get all the bend in one try, but bend it up a little, try the trigger block safety for tension by pushing it up from the bottom behind the trigger. Continue bending and trying until you can easily move the safety block up with your finger. Leave enough tension so that the safety block always returns to it's down position.

Now look at the long leg of the spring where it bears on the rear of the trigger. Pry it up a little at a time to relieve some tension on the trigger. Be careful and don't kink the spring. You are only trying to relieve some of the tension. It is better to error on the safe side rather than having to buy a new spring.

Some people feel that the floppy two-piece trigger/sear in the Marlin is undesirable. There are after market one-piece triggers available to replace the Marlin trigger. These replacement triggers are also advertised to reduce the trigger pull weight and all the comments I have seen regarding these triggers has been positive.


See Eight Bits guidance for working on the Marlin Sear (Requires a special tool available from Brownells ) I understand that working on Trigger/Sear is a safety related item and accept responsibility for any work I do.
LOCKING BOLT

Check for any burrs and polish the sides and any burnished areas. Do not remove any metal or change the shape.

BREECH BOLT

Place the bolt back in the action and slowly slide it back and forth. It should move smoothly through out its length. Check for any burrs on the bolt and in the receiver and polish them out if you find any. Pay attention to the slot in the side of the bolt where the ejector rides and carefully polish the slot's sides and bottom. Wrapping a small piece of the 600-grit paper around a narrow file or Popsicle stick easily does this. Carefully polish the cam on the bottom of the bolt where it rides over the hammer nose. Do not reduce the height of the cam. Polish it only.

McPherson's gives detailed instruction on how to narrow this cam to reduce the friction as the bolt rides over the hammer. This modification, in my opinion, is not for the faint of heart and should only be attempted by the advanced amateur or professional gunsmith. Bolts are not cheap should you have to replace it.


Like the objection to the two-piece trigger/sear, some object to the two-piece firing pin. Theory is that the two-piece pin requires more force from the hammer to fire the primer, especially when the hammer spring has been reduced. After market one-piece firing pins are also available. In his book, McPherson details how to modify the existing firing pin to lighten it so I will leave it at that.

HAMMER & HAMMER SPRING

Remove ¾ of a coil from each end of the hammer spring. If you use a grinder to do this, do not get the spring too hot to hold or allow the spring to change color. Go slowly and grind the cut off end flat like it was done at the factory. If you do not have a grinder, use a triangular file to file a groove in the coil and break the end off. Then file it flat. A Dremel tool with a cutoff blade will also work to remove the ¾ coil. In all three cases, do not nick the adjacent coil as this will set up a weak spot for future breakage. The hammer spring, due to its barrel shape, goes away very quickly. Should you remove too much, you will find that it will not reliably, maybe not at all, provide enough force to fire a primer. If this occurs, and you do not have a spare spring, do not despair. Locate, in your parts drawer or at the local hardware store, some small, thin washers that will just freely slip over the hammer strut. Place one on each of end of the spring and try to fire a primer in an empty case. One washer on each end will most likely provide enough power to fire a primer.

Reduced force after market main springs are available for those who desire to purchase them rather than modifying the existing spring.
Using the wet or dry paper, polish the hammer strut on both sides and both edges. Check and remove any burrs from the hammer pivot hole. Polish the hammer screw where the hammer pivots.
Check the sides of the hammer for bright drag spots. A burr in the receiver rubbing against the hammer can slow the hammer fall. Remove any burrs.
Remember the 3/32" hammer over travel referred to above? Some of this can be removed by grinding the nose of the hammer down using a belt sander or fine grinding wheel. If you feel uneasy about removing metal from the hammer, skip this step. You need to remove approximately 1/32" (.031"). Filing the hammer nose is not practical due to radius and the requirement to maintain the exact contour. Carefully grind and polish the hammer nose. I do not recommend removing more than 1/32" (.031"). This will assure that the hammer is sufficiently depressed to be held at full cock. Scribe lines on both sides of the hammer nose following the same contour and remove metal to this line. A better method of assuring that you don't remove too much is to use a vernier caliper and measure from the flat on the bottom of the hammer to the nose. Go slowly, measure often and then polish the nose. Be advised that altering the hammer may void the manufacturer's warranty.

CARRIER ASSEMBLY

Leave the sides alone. Polish all burnished areas where the lever acts on the carrier. Look for brass colored areas where brass rubbed off and polish those areas as well. Check the screw hole for burrs and remove. Polish the screw where the carrier pivots.

EJECTOR

Check for burrs and polish as required. Polish the cam area where the bolt pushes the ejector down into its slot in the receiver. Spring tension on the ejector can be reduced by carefully bending the spring toward the ejector. Again, an after market one piece ejector/spring is available.

MAGAZINE PLUG & SPRING

Remove the magazine tube plug and remove the 10 shot plastic plug from the spring. Replace the magazine tube plug and you can now load 13 rounds in the magazine. I don't recommend that you remove any coils from the magazine spring unless it is hard to load rounds into the magazine. If you do decide to remove any coils, proceed slowly and try often for proper feeding. Be safe, leave this spring alone.

Some people find the orange magazine follower objectionable. Its good point is that it is easy to see through the loading gate to verify that the magazine does not contain any live rounds. Some feel that the plastic follower contributes to rust forming in the magazine tube. While this may be true, a more likely reason has to do with the fact that few people remove the spring and follower and clean the inside of the tube much like they would a shotgun barrel. For those individuals with a lathe, a replacement follower can be made out of aluminum bar stock. It too is easy to see through the loading gate.

SAFETY

Everyone complains about the safety. However, it does have a couple of good traits. One, it allows you to safely cycle rounds through the action to unload the magazine without the danger of an accidental discharge. Two, you can dry fire occasionally without danger of breaking a firing pin.

Five things can be done to the safety.

1. Leave it alone and use it when desired.

2. Replace it with an after market dummy that fills the hole and appears as a bolt.

3. Remove the stock. Turn in the safety set screw enough to lock the safety in the off position so that it can't be applied accidentally.

4. In a lathe, face off the left end of the safety so that it is flush with the left side of the receiver when in the off position. The safety can be applied by pushing on it with the end of a pencil.

5. Remove the safety, go to your friendly hardware store and purchase an "O" ring that fits the grove in the safety. After reinstalling the safety, slip the "O" ring over the left end. This will prevent the safety from being applied accidentally.

I have fired several thousand rounds through my Marlins and have never had my safety accidentally placed in the on position.

REASSEMBLY

Reassemble the rifle in the reverse steps to disassembly. Put a light coat of oil on all parts prior to reassembly. Do not tighten any screw all the way until everything is back together. Then snug up all screws. Cycle the action several times to assure everything is working smoothly. On my Marlin 1894, if the trigger guard plate support screw is too tight, the action will appear sluggish. If this occurs on your rifle, back the screw off very slightly.

LOOSE SCREWS

Every Marlin I have observed suffers from screws loosing up during heavy shooting. The most common is the carrier screw, but the hammer screw and the trigger guard plate support screw also may loosen. Keep a screwdriver close by when shooting and retighten the screws as required. A better solution is to apply a SMALL drop of blue Loctite to the threads of these screws. Loctite can be easily applied to the threads on the left side of the receiver using a toothpick. DO NOT USE RED Loctite or you may never take it apart again.

You have now tuned up your Marlin and are ready to enjoy a great rifle.


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Updated on 3/4/2003 By Our Excellent Staff Email:marauder13056@yahoo.com

Fixing the dreaded “Marlin Jam”
By Rusty Marlin
The Problem

The "Marlin Jam" as it is affectionately known is caused by an inherent design/manufacturing flaw of the Marlin lever. The lever has a snail shaped cam surface that goes around the pivot screw. This snail shaped cam rides on a sloped surface on the bottom of the carrier and raises the carrier enough to allow the first incoming shell into the carrier and to block the next incoming round from jamming up the works. Every time the lever is cycled the carrier bounces on the forward edge of the cam. The forward most edge of this cam is left sharp at the factory (the flaw).




The bouncing forges a notch into the bottom of the carriers' slide surface and over time (high number of cycles) lowers the carriers' initial pick-up height allowing the rim of the next incoming shell to slip over the front and jam it up tight. Note the notch labeled A in the photo.


Simply changing the carrier out as many repair places do is only a temporary fix at best. The new carrier will get a notch forged into it from the sharp edge of the lever cam and over time will settle downward in the action and again give you the “Marlin Jam”. Following the steps below will cure this problem FOREVER.

The Cure for New Guns

With new guns (less than 50 cycles) you can generally get away with just putting a radius on the forward edge of the lever cam. While this will lower the initial pick-up height slightly, it typically will still be high enough to prevent the dreaded "Marlin Jam" from ever occurring. If your rifle jams you will need to follow the steps outlined above.

Many of you will have guns that jam once and a while but haven't figured out why. You probably have an odd piece of brass or two in your collection. For example the gun might run fine on Starline or Winchester but lock up tight on R-P. R-Ps are slightly smaller than others and this will cause the problem to be sporadic. Eventually the gun will jam on anything you feed it and you will need this fix.


The Fix for Used Guns
Three things are required to fix the problem. The first two prevent it from ever occurring again and the third retimes the carrier to proper height. Don’t even bother to do them if you aren’t going to do item 2A or item 3.

1) Put a generous radius on the front edge of the snail cam on the lever. I use between a .025 and .035" R. This radius spreads the load out from the force of the carrier bounce and prevents the forged notch from reoccurring. You will notice a shiny line will form but it won’t be a notch like before. The large radius also self limits how deep it can forge into the softer carrier.

2A) Order a new carrier from Marlin. If you do this, you will be done, other wise, read on...

2) Grind the slip cam surface on the carrier to just remove the forged notch.
These two items will make the problem worse until item three is done.

3) Bend the carriers' nose up about .05".

Use the heat and bend method described below.

Clamp the carrier in a large bench vice so the pivot hole axis runs vertically. The two parallel faces at the pivot hole end need to be clamped in aluminum blocks for a heat sink. If the heat gets to the plunger spring you will need a new carrier, so the heat sinks are very important.

Heat the neck just behind the front of the carrier till dull red. Position a block of steel (or brass) just behind the shell stop (tang that hangs down in front) and tap the head "up". This is actually going to be parallel to the floor.

Measuring this movement can be difficult. I gave up trying after the first few and now it’s by eye. After cooling try it in the gun. If you went too far the very first incoming shell will jam as the lever is opened; the carrier will wedge it up against the top of the magazine opening. You will need to heat the carrier again and tap it back a touch.
This retimes the carriers' initial pick up height to let one round in and keep the rest in the magazine.

Rusty Marlin, SASS #33284


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kenjuudo
03-25-2005, 10:56 PM
Scrounger--Many thanks!!

jim

imashooter2
03-25-2005, 11:55 PM
Here's an exploded view to go with the text:

http://www.gunuts.com/images/40.jpg

kenjuudo
03-26-2005, 09:32 AM
imashooter2- That helps alot, I try to put together a binder for all my guns, you guys are saving alot of surf time.

I have no need for this rifle, but do have a Fat 30 mold and a couple hunnert rounds of brass, so now at least the brass won't go to waste...that makes sense...kinda...don't it?

jim

Dutch4122
03-26-2005, 10:32 AM
Since it's your first I'll just say be very careful. These Leverguns can become a serious addiction. :wink:

castalott
03-26-2005, 11:32 AM
Hi All!

Leverguns are a serious addiction. I am in rehab right now!

I once polished a restriction out of a Ruger target pistol. A tight patch with metal polish was used. It went from 6 inch groups at 25 feet to one hole clusters. It took most of an afternoon. I only polished where the restriction was.

I DON'T RECCOMMEND THIS...

My results were excellent but the patch method would have to remove metal everywhere...even where it did not need to be removed. Would a pored lead 'patch' be better? I would think so but have never done this.

I think I will like this place.....so many cool people....

Dale

Oldfeller
03-27-2005, 10:12 AM
I had a microgroove with a restriction at the barrel threads and a more abrupt much larger one under the front sight dovetail. I tried to lap it out with slugs attached to a cleaning rod which didn't work very well. There was no mechanical leverage to force the slug through the restriction (I bent the cleaning rod and loosened up the wooden fore arm trying to lap it out with a rod mounted slug).

Very little metal removal was accomplished.

Fire lapping was more effective, but hit a lap limit very quickly. This practical fire lapping limit was based upon the VERY SHORT microgroove rifling height. I could not remove the restriction completely without destroying the rifling height.

Now the good news, smoothing the barrel and removing only 3/4 of the severe restriction under the front sight dovetail still resulted in a remarkably accurate microgroove Marlin 30-A.

Heck, one day I may actually get a chance to shoot it again ....

Oldfeller

Rrusse11
03-27-2005, 01:41 PM
imashooter2- That helps alot, I try to put together a binder for all my guns, you guys are saving alot of surf time.

I have no need for this rifle, but do have a Fat 30 mold and a couple hunnert rounds of brass, so now at least the brass won't go to waste...that makes sense...kinda...don't it?

jim

Ken,
Like Dutch said, be VERRRRY carefull, :lol: . The simplicity of the action is beautifull, and with the tuning tips presented, you'll be amazed how ez it is to make a remarkable difference in action slickness.
Two of the biggest points that I've found on my Marlins is polishing and relieving the bolt/hammer contact zone, and the ejector groove in the side of the bolt. Carefull stoning and polishing of the wear points on the cartridge lifter, sides of the hammer and the receiver itself where the bolt slides and you'll have in a couple of hours what the specialty smiths charge a $100+ for.
Lengthening the action by working on the cartridge stop is a VERY usefull bit of work, getting an additional 75-100 thou of COAL enables boolit engraving in the lands, they usually have short throats anyway.
Hand lapping DOES help, and particulary with ur "NIB" bore, JB's, and carefull breaking in with jacketed will noticeably improve accuracy.
On the external tuning, try and 'float' the barrel and forend as much as possible, releiving the forend wood, and forend barrel bands/caps will improve 'groupability' and consistency. The magazine tube should be just a tad short, and make sure that is a smooth fit into the receiver.
Welcome to the world of Marlins, the 336's IMO are one of the unsung bargains on the second hand racks.
Cheers,
R*2

Rrusse11
03-27-2005, 01:50 PM
Ken,
Once you've got the bug,,,,,,,,,

http://www.marlinowners.com/gallery/albums/userpics/thumb_M93TD30-30.jpg

http://www.marlinowners.com/gallery/albums/userpics/thumb_1893Set%7E0.jpg

here's where it can take you, :) .
R*2

Ps. Or try this link for a better view.
http://www.marlinowners.com/gallery/displayimage.php?album=lastup&cat=10048&***=7

kenjuudo
03-27-2005, 02:30 PM
Ran a box of factory through it yesterday, cleanining between the first 5, then after each five for the rest of the box. Bore was noticeably smoother feeling with a very tight patch when done.

Ran another box through it today, best use I ever had for Easter eggs!!! I think I'm just gonna run a few more boxes of factory through it and see how she does on lead, might be fine for all I know.

Not much chance of this becoming an addiction, I have a couple dozen handguns, been shooting them for years and I ain't hooked on them yet :lol: :lol: :lol:

jim

Rrusse11
03-27-2005, 02:43 PM
Jim,
You've got handguns????? Well then, what you really really wanna' get is a Marlin 1894 in either 44Mag or 357,,,,,,, astonishing what dem lil cartridges can do in a rifle.
Been having a blast with the 218Bee in a M1894CL, lol, now I'm eyeing off the Taurus revolter in same.
Cheers,
R*2

kenjuudo
03-27-2005, 07:37 PM
Jim,
You've got handguns????? Well then, what you really really wanna' get is a Marlin 1894 in either 44Mag or 357,,,,,,, astonishing what dem lil cartridges can do in a rifle.
Been having a blast with the 218Bee in a M1894CL, lol, now I'm eyeing off the Taurus revolter in same.
Cheers,
R*2

I'd check out a Taurus anything very carefully, Ive had less than rotten luck dealing with them on quality issues. I do have two decent ones though.

Rrusse11
03-27-2005, 09:20 PM
I'd check out a Taurus anything very carefully, Ive had less than rotten luck dealing with them on quality issues. I do have two decent ones though.[/quote]

Ahhhh, thank you for the warning. Been avoiding 'em so far. Mebbe convert one of the Ruger 22's,,,,,,,,
Cheers,
R*2