Ruger MKIII failure

saserby

Guys,
I've been getting some failure to fire in my Ruger MKIII. It's cheap ammo, but the failures never occur in the first 3/4 of a magazine. Always on round 8,9 or 10. Firing pin strikes light. Refeed same shell and they always fire. Also, many of theose same FTF shells also fail to extract. I push the shell out with a rod, manually reinsert, shell fires.

Any ideas?

pingjockey

Sounds like a rough chamber might be keeping the shells from
seating completely. Dry firing can cause a "tight" chamber by
peening the edge of the chamber. Rim fires can be fussy, the
rim normally needs to be pinched by the firing pin and if the
shell isn't all the way in, the shell is just moved slightly
forward in the chamber resulting in what looks like a light
strike. As to the "last three" problem, I'm not sure what that
might be other than heat.

rufe-snow

Ruger lawyer proofed their Mark II models by adding a magazine safety and a loaded chamber indicator, these became the Mark III's.

Lot of folks have had problems with the Mark III's malfunctioning because of these two lawyer mandated safety features.

You might consider going to the "Rimfire Central" .22 enthusiasts site. The Mark III's are a very hot topic over there. Many folks have had problems similar to your and have worked out various fixes, to correct them.

brier-49

You have got to pull it apart & clean it!

rawhide54

Try different magazines. My MK II has never given me trouble but the MK III I got for my son acted like yours. Turned out to be the magazines. Made no sense to me but had a Ruger technician send me two new mags and no trouble since. Something to do with the damn magazine safety. Still get a few misfires when use Remington Thunderbolt ammo but that happens with all my .22's.

saserby

I'm going to take it all the way down this weekend and clean thoroughly. I have about 800 rounds through it. I have cleaned it, but never removed the firing pin. I've been advised the firing pn channel can get gummed up slowing down the pin. Also, I agree with pingjockey that the chamber seems to be an issue because I also get a failure to eject on occasion with a stuck shell, typically after a weak strike.
I'm putting it all together and it's leading to poor maintenance by me.[B)] I will be very happy if that is the case. Much better that than something beyond my control.

I'll give you a range report this weekend. (if I can get it back together in only two days. That darn thing is tricky.[:)])

andrewsw16

Reference peening by dryfiring, that was true on older .22 pistols and rifles. I contacted the Ruger service department and they confirmed the Ruger pistols were made with firing pins just short enough to where they should not touch the chamber face, therefore can't peen, and are safe for unlimited dry firing. So, the problem is one or both, rough chamber and/or dirty bolt/pin. You can remedy the rough chamber with a bore brush wrapped in 0000 steel wool and chucked into your drill. Insert it in the chamber and spin it until that baby shines like a mirror. Keep the brush/wool slowly moving in and out as you run the drill.
As for the bolt, TOTALLY disassemble it and clean out the firing pin channel and bolt face. Check for any roughness on the firing pin and polish it if necessary. Don't lose the little firing pin recoil spring and attachment.
Lube and reassemble. That should take care of the problem. [:)]

(editted) Good luck. That itsy bitsy teeny tiny firing ping return spring mechanism can be crucial. If the firing pin doesn't fully retract after each shot, it won't get a good smack by the hammer on the next shot.

saserby

OK, So it was bothering me and I was just sitting here drinking a beer, so I decided to go clean it. So I spent the last hour working on it. I pulled the firing pin. Not as dirty as I was hoping, but it was gummed up a bit. Also, the return spring and bolt face were pretty dirty. I worked it over pretty good including the chamber and barrel.

So, it's clean as new now. We'll see tomorrow if that solves the problem. I'll give you a range report. Thanks for the tips.

saserby

So I did the steel wool on a cleaning rod in the drill trick this morning. I was surprised how much cleaner the bore looked after I had already cleaned it last night.

I put 50 rounds through it with not one misfire.[:D]

Thanks for the advice!