[BigDeal]

I picked up one of these at a local pawn shop for my 14 year old son some time ago, and finally had an opportunity to get out and shoot it this weekend. Well kinda. The gun functions fine (i.e. chambering a round and cocking the action) but when I pull the trigger, the firing pin apparently is not impacting the chambered round (no shown impact of any sort on the back of the round(s)). I manually cycled several rounds through the gun with the same result every time.

Since I'm no gunsmith (but am fairly proficient with disassembly, cleaning, minor service, and reassembly of the remainder of my firearms) I'd like to take a stab at fixing whatever problem is afflicting this little gun. I've dis-assembled the gun and removed the bolt assembly, and the firing pin in floating free and the tip does not appear to be broken. I cannot however determine if the tip is worn sufficiently to be causing my problem.

Anyone here have any suggestions of possible causes for the problem I noted? Any known issues similar to the one I have described? I've already downloaded and reviewed the Marlin 60 manual, and the internals of the gun appear to be rather simple.

Any help you could provide would be greatly appreciated as having a neat little guin that does not function is the pits.

Thanks in advance for any help you can provide.

 

[ArrowDodger]

I wonder if the bolt is closing all the way when the hammer falls. Are the notches clean where the extractors enter? Another thought would be to see if the firing pin extends beyond the bolt face when you press the rear end of it flush to the backside of the bolt.

 

[scooter22]

Next time you cycle the action and feed a round, push the bolt handle forward and see if it's fully closing. Then try firing it. Also look at the internal hammer. I had one back in the 80's that a section broke off and became intermittent at hitting the FP. Should be a easy fix. Good shooting.

 

[dangerranger]

after checking Arrow dodgers sugestions take the trigger out and examine it closely where the rear screw passes through. Ive not had it happen myself but enough people have found a crack there. the other thing thats comon is make shure the action is all the way back in the stock before tightening it down. thats my two posibilitys. DR

 

[GJinNY]

Welcome BD,

Hmmmmm,

So you never shot it since you got it?

If Yes,

Does it sound like the hammer slap the back of the bolt when you pull the trigger?

With just the bolt in the receiver, does the bolt face go all the way to the barrel?

Is there any gap between the two?.

Does the firing pin extend forward enough out the channel to strike a brass rim?

If you shake the bolt, is the firing pin loose enough to move back and forth in the channel?

Does the back of the firing pin stick out of the back of the bolt when you push it in from the front?

If you never shot it before:

Are you sure the lower receiver action is assembled correctly?

Does it look like someone had been working on the lower receiver action before you?

 

[BigDeal]

Welcome BD,

Hmmmmm,

So you never shot it since you got it?

If Yes,

Does it sound like the hammer slap the back of the bolt when you pull the trigger?

Yes....It sounds as if the hammer falls and impacts something internally.

With just the bolt in the receiver, does the bolt face go all the way to the barrel?

Is there any gap between the two?.

Will re-assemble and check fit. Did not pay close enough attention previously to be sure.

Does the firing pin extend forward enough out the channel to strike a brass rim?

The firing pin does extend beyond the bolt, but how far should it extend? It doesn't look excessively worn or broken (at least to me), but I have no clue how far it should extend.

If you shake the bolt, is the firing pin loose enough to move back and forth in the channel?

Yes.

Does the back of the firing pin stick out of the back of the bolt when you push it in from the front?

Yes.

If you never shot it before:

Are you sure the lower receiver action is assembled correctly?

I have no idea. I did try and compare, as best I could, the action to the exploded diagram in the Marlin manual.

Does it look like someone had been working on the lower receiver action before you?

Again, I can't say for certain. However, it does not appear that the pins have been pressed out of the action or bolt.

 

[dangerranger]

If the hammer went forward you will feel the extra force needed to cock the hammer when you pull the bolt back. how old is the gun? if it has an aluminum trigger guard its old enough to have the old style hammer thats forked on top. these are the only hammer styles that Ive seen broken. how about some pics?

 

[GJinNY]

BD,

Did you say you have not ever shot it yet to know if worked when you bought it?


As for making sure it is assembled properly, check the STICKY at the top of the Semiautomatic page for a great powerpoint series of pics on the teardown of the lower receiver. Compare to what you have , watch for springs and part positions too...

 

[BigDeal]

If the hammer went forward you will feel the extra force needed to cock the hammer when you pull the bolt back. how old is the gun? if it has an aluminum trigger guard its old enough to have the old style hammer thats forked on top. these are the only hammer styles that Ive seen broken. how about some pics?

Don't know the age of the gun, but the trigger guard/group is nylon/plastic, so its not ancient. Does Marlin offer the ability to use the gun's serial number to determine its age? Let me know and I'll figure out how old it is.

Oh, and it does feel as though the bolt 'is' cocking the hammer when I pull it back.

 

[GJinNY]

Take the 1st two numbers of the serial number and subtract from 2000. That is your year of mfr.

16XXXXXX = 1984 pretty easy eh?

 

[BigDeal]

Take the 1st two numbers of the serial number and subtract from 2000. That is your year of mfr.

16XXXXXX = 1984 pretty easy eh?

Then...... 2000 - 18 = 1982

 

[GJinNY]

Bingo!

Now, can you take the lower receiver out and put up a pic of a top view and a bottom view. Maybe we can see something.

 

[BigDeal]

Bingo!

Now, can you take the lower receiver out and put up a pic of a top view and a bottom view. Maybe we can see something.

Yes. Will get some pics up as soon as I can this afternoon or this evening.

As an aside, things got slow here this afternoon (I work for myself from home) so I've been further exploring this thing a bit. What I've verified so far....

1. The bolt does indeed cock the action and hammer.
2. The hammer does not show any damage.
3. The hammer falls when engaged by the trigger.
4. The hammer 'does' impact the firing pin and moves it forward.
5. The firing pin does extend beyond the front of the bolt, and appears to extend far enough to impact a chambered round. Whether it extends as far as it should, I can't say for certain.
6. The lower receiver appears to be assembled correctly and functioning appropriately (will put up some pics shortly).

Through playing with the internals of this gun, I've found them to be very simple compared to many of my other guns, which is good. However, it does make it exceptionally frustrating given I can't seem to determine why such a simple mechanism won't work.

 

[BigDeal]

I tried one more quick function 'test' this afternoon. I know this might possibly be viewed as irregular, but bear with me. I disassembled a couple unfired .22LR rounds, discarded the bullets, emptied out the propellent, and then swabbed out the casings with a Q-tip to render them totally inert. I then reassembled the bolt and the upper and lower receivers (did not re-install the stock), chambered one of the inert rounds, and manually dropped the hammer with a screwdriver (gun was however pointed at the floor), then removed the round to evaluate the hit it took from the firing pin. The inert round showed almost no point of impact whatsoever on the rear of the casing, just a very, very, slight depression. I'll also try and get a pic of this up later for your evaluation.

I haven't spent a lot of time in the past few years shooting a .22, but shouldn't the firing pin leave a rather defined square or rectangular indentation in the rim of the casing? I'm now starting to really suspect that the gun has a worn firing pin.

 

[ShootsAtSky]

Sounds like you've been over the action and bolt pretty well. Add that to a fairly recent model that's not likely to be too worn and the next most likely is just some additional cleaning.

Blow back rimfire actions have a spot that needs much more cleaning than your bolt action centerfires. The bolt and casing start back and actually clear the chamber while there's still some pressure and lots of crud in the bore. That leads to packing crud under pressure into both the extractor cut outs on the barrel face and into the ejector cuts in the bolt. Crud build up in these areas, particularly in the barrel face can be so hard and dry that it can be mistaken for part of the barrel. Try cleaning the extractor cuts in the bolt face with a dental pick or very small jewelers screwdriver and see if you get a surprising amount of crud out.

That's what GJinNY was leading to when he asked if there was a gap between the bolt face and the barrel face. Crud in the extractors and extractor cuts can stop the bolt face from going fully forward. That means that the round isn't completely seated in the chamber, leaving you with either a firing pin that can't quite reach the rim if the round is forward, or it hits the rim but the round is free to move forward into the chamber instead of crushing the rim against the barrel face. That gives you very light strikes or no strike at all, even with everything else working correctly.

You can also have lead buildup on the bolt and barrel face that causes a very similar problem, but that's usually easier to see.

Next up would be that someone's put it back together wrong, and you've been reassembling it based on their error. That's why everyone wants pictures, that and we just like looking at guns.

Bob

 

[ArrowDodger]

1982 .... hmm is that before LSHO? Time for a new firing pin.

 

[ShootsAtSky]

1982 .... hmm is that before LSHO? Time for a new firing pin.

You think so? He did say that it's coming up to the bolt face and no obvious wear on the tip.

Bob

 

[JAB]

Do you have a micrometer? If the other's suggestions don't work I can only think of one other thing, but it's a very long shot. If you have exessive headspace it could cause the same issue if you had alot of crud built up on the bolt face or in the slots for the extractors. I highly doubt it's your issue though. To measure your headspace you just measure the recess in your bolt where the case sits, I would also measure your firing pin protrusion also.

 

[ShootsAtSky]

BigDeal,

Your test is completely valid, I keep a handful of clean fired cases to use the same way. The firing pin on the M60 is a 'chisel' design, which should leave a fairly deep rectangular dent in the case rim, extending about 1/3 of the way from the rim to the center of the case. The firing pin should not be sharpened like a chisel, that can lead to a blown out rim.

Just realized that no one had really answered your question about how far the firing pin should protrude from the bolt recess. It's a fuzzy answer, you want it to protrude as far as possible, but absolutely not to extend past the bolt face itself. It must be long enough to drive the close edge of the rim into the back edge, crushing the primer in between the rim surfaces. The metal in the case is generally .010 inch, so to crush the primer the gap should be less than the two pieces combined > .020. But, you don't want it to ever hit the barrel face during a dry fire, that can peen a dent into the chamber that will then cause hard loading and ejection failures.

Here's a couple pics of another firing pin, it's from a Stevens bolt, but it gives you an idea of what it should look like and how to check. This one was peened over, but still had good solid strikes.

Edited, I should have used this link in the first place, it also shows how to measure the head space. Personal opinion:: Headspace is not really that important on a rimfire, as long as it's somewhere close. Unless you're trying to get the very last bit of accuracy and reliability anywhere from .04x to .05 it should work fine.

Bob

 

[BigDeal]

Ok, here we go with the pictures. In taking the pics I did notice that the 'Recoil Spring Guide' is bent slightly. I'm sure I can straighten it with a tap hammer on top of my vise, but should I, or should I buy a new guide? Alternately, does it being bent make a real difference anyway?

Lower Receiver - Bottom

Lower Receiver - Top

Bolt (and bent guide rod)

Firing Pin - Extended Rear

Firing Pin - Extended Forward

I tried several times to take a closeup pic of the rim of the .22LR casing is used to test for a strike from the firing pin, but could never get anything helpful to show up.

I also took the time to clean 'everything' very well (I'll wait to lube all the moving parts when I reassemble the gun for the last time). There was no real fowling buildup in the extractor cutouts alongside the chamber or on the bolt face, so we can strike those from the list. Finally, I carefully polished all of the exterior bolt faces with 320, 400, 600, and 1000 grit wet sandpaper, and the bolt now moves almost effortlessly through the upper receiver.

So there you have it. I'm all ears if you can see or suggest anything else to try.