.22 Marlin Problem

Discussion in 'Technical Questions & Information' started by hamman88, May 4, 2009.

  1. hamman88

    hamman88 New Member

    Joined:
    May 4, 2009
    Messages:
    1
    I recently bought a junker Marlin .22 bolt action at a show for $25 but I'm having a little trouble with it (as I expected). It will only fire about 1 in 5 tries or less. It gives a dimple on the case each time, but when it does actually fire the dimple is stronger. What could be cuasing these weak strikes (but not always). I've taken apart the bolt, cleaned it and oiled it, the firing pin looks good and the spring seems strong(?). I've also noticed that when I push the bolt handle down after cycling it, the cocking piece (the thing all the way at the rear) moves in a few milimeters (perhaps it decocks?).

    If anyone could tell me what the problem is and how to fix it I would really appreciate it.
     
  2. LDBennett

    LDBennett Well-Known Member

    Joined:
    Dec 20, 2003
    Messages:
    8,581
    Location:
    Hesperia, CA
    When you pull the bolt to the rear the firing pin is transfered from the sear holding it back to a cam on the bolt body. When you return the bolt forward and turn it to close it, the firing pin is transfered back to the sear to hold it back. That would result in a small forward motion of the firing pin as the bolt is closed.

    If the firing pin does not get a "full stroke", it could have insufficient energy to set off the priming compound in the rim of the 22 cartridge. It may be the sear/firing pin engagement surface is screwed up and the firing pin is not held all the way back by the sear everytime. Measure the firing pin rearward projection for the situation where the gun fires and when it doesn't. If the rearward protrusion is different, the problem is in the engagement of the sear and the firing pin. It could be either the sear or the firing pin engagement surface is broken or screwed up.

    LDBennett
     

  3. Helix_FR

    Helix_FR Active Member

    Joined:
    Apr 14, 2009
    Messages:
    3,732
    Location:
    Imperial, MO
    other issue is that the round is not held to the bolt face within spec. or the extractor does not have a firm hold on the rim of the round. When the pin fires it may be pushing the bolt back or pushing the round forward therefore leaving a gap between the bolt face and the round. Chamber a spent 22 round and chamber it. pull the trigger and see if you get any movement in the bolt. Movement in the round is harder to see but less likely b/c the extractor should have a firm hold on it. Pull the bolt and see if the extractor will hold on to the spent case on its own. Extractors don't play a major part in firing the round but they are responsible for holding the round to the bolt face.
     
  4. LDBennett

    LDBennett Well-Known Member

    Joined:
    Dec 20, 2003
    Messages:
    8,581
    Location:
    Hesperia, CA
    Helix_FR:

    I re-read your post multiple times and I really don't understand it. Here's what I understand:

    As the round is feed up into the chamber on most guns the bullet nose enters the chamber before the rest of the cartridge is parallel to the bore. Admittedly some guns allow the cartridge rim to flip up under the extractor but it is not necessary as the front edge of the extractor can just push the cartridge into the chamber without the extractor being over the rim. The cartridge can feed without the rim ever going under the extractor. On most 22 cal. guns there is a cut in the end of the barrel that pushes the extractor outward, disengaging it from the rim when the bolt is full closed. The extractor grabs the rim as the bolt is opened and pulls the empty case from the chamber.

    Holding the cartridge to the bolt face is normally not necessarily required as one of the duties of the extractor before the firing of the gun. It is only after the round is spent and the bolt opens that the extractor needs to hold the cartridge to the bolt face, and that's for extraction. I don't see how the extractor plays any part in the action of the firing pin once the bolt is full closed. No gun I know of holds the rim of the case to the bolt with the extractor for the firing pin strike to be successful. The chamber and or the bolt are so made as to confine the rim of the 22 case with a minimal headspace between the bolt face and the back of the cartridge if the cartridge rim is seated against the barrel face. The extractor does not come into play at all. It is cam'ed out of engagement with the rim by the angle cut slot in the barrel face.

    It could be that the cut in the receiver that cams the bolt tightly closed or the bolt handle base that engages that cut might be so worn that the bolt does not full close and the headspace is excessive. But that does not seem to match what is happening to hamman88 in his description of the problem.

    Did I miss something here????

    LDBennett
     
  5. Helix_FR

    Helix_FR Active Member

    Joined:
    Apr 14, 2009
    Messages:
    3,732
    Location:
    Imperial, MO
    No you didn't miss anything I guess my description is a little off. what has me questioning the extractor is the inconsistency of fire. Yes your correct on the extractor moving out of position but I had a marlin do something similar. The extractor was not totally moving out of position therefor leaving the round offset. There was enough headspace to allow this. The bolt fully closed but pinched the rim. When the pin stuck it was a light strike b/c of the excessive gap. I guess I should of just said, check the head spacing or for excessive play in the bolt lockup.
     
  6. LDBennett

    LDBennett Well-Known Member

    Joined:
    Dec 20, 2003
    Messages:
    8,581
    Location:
    Hesperia, CA
    Helix_FR said:

    "check the head spacing or for excessive play in the bolt lockup."

    Now, that I understand and indeed could be a problem. Gun problems are very difficult to solve without the gun in hand. Simple checks that I do without even thinking are often overlooked when trying to describe fixes to gun problems.

    Through the years I have owned or had friends that have owned Marlin rifles. I have NEVER been impressed with any that I have seen. They are utilitarian in fit and finish and each suffered badly in the accuracy department. But that is just my experience and yours may differ. Stupid problems from a Marlin rifle does not surprise me.

    Sorry Marlin lovers but that is my opinion and yours may differ.

    LDBennett
     
  7. Helix_FR

    Helix_FR Active Member

    Joined:
    Apr 14, 2009
    Messages:
    3,732
    Location:
    Imperial, MO
    I'll back you up on that LD. I have 1 marlin rifle and its not bad but not great. Great utilitarian rifle. Friend of mine loves them but he just loves to plink and they are good for that. Thanks for calling me out LD and having me elaborate. After reading my own post I was dumbfounded on what I was trying to say.:confused: I had a tooth pulled yesterday morning and I was really loopy. Getting on some of the forums is about all the energy I had yesterday. It must have been the novacane typing for me. Hamman88, let us know of your findings.