I've just sent my mini back to the factory as it was misfiring about 2 of ten times. There would be a very slight mark on the primer and the same rounds, when reinserted, would fire fine. The ejection system worked fine and recharging the next round would work fine. Again, about 2 of ten would misfire. Any ideas as to why this was ocurring? I hope the factory can find the cause as it is a law enforcement weapon and I cannot affort not to rely on it.
Mini 14 question
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Actually, if you sent it into the factory, they should be able to find the problem. There is another poster on this forum (I forget the name, sorry), who sent in his Mini-14, only to find out that there were Mini-30 parts in it! That could be the cause. Otherwise a somehow shortened firing pin, or possibly something in the trigger mechanism interfering with the hammer fully traveling.
I have been having the same problem with mine and I have yet to resolve it. There were a few things I wanted to try but I havent been able to get out and shoot lately. What brand mags are you using?? Feel free to check out the posts about this topic, the thread is titled "what gives". Thanks.
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Typical of Ruger.
This post caught my attention because I have a customers Mini that is doing the same thing. Same symtoms as you describe.
History: I had previously glass bedded it, lapped the barrel, trigger work, etc. He was using some cheap re-mfg ammo and it was working just fine. But he was having some problems getting good groups with a Norinco scope. After talking it over with me, he latter determined the scope was shifting. He switched scopes and got much better accuracy (can't remember sizes) but it was good enough to warrent better ammo so he switched to Black Hills per a buddies recommendation. That's when it started failing to fire. He called me back up again and tried to explain the problem. Only he didn't mention switching ammo. I naturally concluded he was shooting some cheap steel cased stuff (which I've heard people having problems with the primers not igniting.) I suggested we check the hammer spring (although I already knew it was fine because I did the trigger work) and take a look at the rifle together. I asked him to bring some of the "duds" as he called them. I found a very slight hint of a mark on the primers. (not even a true FP hit) OK, the firing pin is not hitting the primer. WHY? Found that the black Hills ammo head spaced pretty tight in this rifle. I natually questioned wether the bolt was rotating enough to lock and line up with the cut for the firing pin block. Appears to cycle by hand just fine. But if you let the bolt down softly on one of these Black Hills cartridges it does hang up ever so slightly. I tried some of my own ammo and it to hung up slightly when cycled softly. But rack it hard and no problem. Haven't had a chance to take it to the range yet but I certainly don't find anything obviously wrong with the rifle. All I can say is that the fire-pin doesn't appear hit the primer.
Oh he did mag mags when he changed scopes & ammo. He is now using a plastic "Eagle" mag I think. The mag has a lot of upward follower pressure and also check to see if that was an important variable in this, but it didn't seem to mater.
Let me know if any of you have anyother ideas.
Mike in Oregon
PS: I'm going to have his try it again with old ammo, new mag. And new ammo, old mag.
This post caught my attention because I have a customers Mini that is doing the same thing. Same symtoms as you describe.
History: I had previously glass bedded it, lapped the barrel, trigger work, etc. He was using some cheap re-mfg ammo and it was working just fine. But he was having some problems getting good groups with a Norinco scope. After talking it over with me, he latter determined the scope was shifting. He switched scopes and got much better accuracy (can't remember sizes) but it was good enough to warrent better ammo so he switched to Black Hills per a buddies recommendation. That's when it started failing to fire. He called me back up again and tried to explain the problem. Only he didn't mention switching ammo. I naturally concluded he was shooting some cheap steel cased stuff (which I've heard people having problems with the primers not igniting.) I suggested we check the hammer spring (although I already knew it was fine because I did the trigger work) and take a look at the rifle together. I asked him to bring some of the "duds" as he called them. I found a very slight hint of a mark on the primers. (not even a true FP hit) OK, the firing pin is not hitting the primer. WHY? Found that the black Hills ammo head spaced pretty tight in this rifle. I natually questioned wether the bolt was rotating enough to lock and line up with the cut for the firing pin block. Appears to cycle by hand just fine. But if you let the bolt down softly on one of these Black Hills cartridges it does hang up ever so slightly. I tried some of my own ammo and it to hung up slightly when cycled softly. But rack it hard and no problem. Haven't had a chance to take it to the range yet but I certainly don't find anything obviously wrong with the rifle. All I can say is that the fire-pin doesn't appear hit the primer.
Oh he did mag mags when he changed scopes & ammo. He is now using a plastic "Eagle" mag I think. The mag has a lot of upward follower pressure and also check to see if that was an important variable in this, but it didn't seem to mater.
Let me know if any of you have anyother ideas.
Mike in Oregon
PS: I'm going to have his try it again with old ammo, new mag. And new ammo, old mag.
OH NO!!!!! My mini is doing it too!!!!!! It started when I switched from Winchester brass to Lake City. Me thinks me fixed it! I thought it was, because the military brass was tough, and eventhough I full sized it, it would misfire. I noticed when it misfired there was just a hint of a fireing pin hit, BECAUSE the bolt dosen't go all the way home, BECAUSE the "Extractor" does not always open enough to grasp the brass, BECAUSE: (1) The chamfer on the case head is very small on the Lake City brass, compared to the Winchester brass. (I'm talking about the very first surface which strikes the extractor, not where the extractor grasps. The smaller the chamfer the larger the surface trying to force open the extractor. Check out your brands of brass) (2) I removed the bolt, and held an empty case on the bolt face, and pushed it in and out a few times (pushing straight in it was dificult), I noticed the radius of the case head did not exactly match the extractor radius, there seemed to be a raised portion on one end of the extractor which formed a burr. The angle of the burr resting on the case head, I could see why it was difficult to open the extractor. Using a jewlers file, fine stone, and smoothing with 600 grit sand paper, I reduced the burr only, and matched the chamfer of the rest of the extractor radius. Cycling it manually it seems to work now, will know for shure when I get to the range. I hope this gives you guys a couple of leads to solve your problems.
My mini was doing this for a while, about once every ten shots or so. Now during the last 150 shots it only did it once, go figure. I am reluctant to send my rifle in to Ruger only because I do not want to part with it for a month. Still I dont like the feeling that it could miss a shot at any given time....let me know how you guys resolve your problems, thanks.
-Grinch
-Grinch
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