It's sounding like one of my marlins developed a dislike for CCI minimags at the last shoot (at 32-40f and raining) - I wasn't there to watch, but it was sounding like a failure to extract. I cleaned the bolt face at lunch and manually cycled a mag through it (unfortunately not CCI), and the issue repeated in the afternoon. The person who cleaned and inspected it that evening (and who knows FAR more about firearms than I) was able to duplicate the issue. Last time I took this one to the range it cycled about a brick of Federal Automatch without issue.
Thoughts and suggestions?
Thanks,
Tom B
Nothing to do with ammo and everything to do with how well it was cleaned and what lubricants were used unless CCI all of a sudden stopped adding as much powder! :) Cycling without shooting isn't a "test". Not to say there couldn't be some worn or broken parts...O.L.
Take this comment with a grain of whatever
From January of this year to the present we (HQ and myself and whoever has grabbed ammo out of our cans) have sent nearly 9000 rounds of CCI minimags and/or Fiocchi's 40gr. copper plated high velocity (which is rebranded MiniMag) through Rugers and Marlins without issue regardless of temperature or conditions. That includes below 0, below freezing, at freezing in the rain, and happy sunny sunshine.
If you cycle a mag without firing you aren't replicating the extraction conditions your rifle experiences. Take that bolt out and check two things. There may be build up in the recessed area that covers the rim of the round. If there is crap built up in there it will become a problem. Then check the extractor itself. Remove it and get a good look at the "hook" that grabs the rim. If there is crud built up in there it won't extract the rim and is easily missed with a brush. In fact, brushes can sometimes force more crud in there. Clean it with a pick and a brass brush and take another look. If it isn't "sharp" consider replacement.
Maybe you have happened to come across the one bad batch CCI/SPEER cranked out but in the last couple years I haven't worked with an instructor that hasn't developed a respect for CCIs poor weather performance. Since the conditions you mention ar getting to the chilly side of damp it may be that the temperature and humidity in the air is causing uncleaned globs of crud and/or excessive lube to build up and get into those hard to reach places.
What SPQR said, between the two of us we have probably run over 15,000 rounds of CCI MM in the last two years, he and HQ more than I by now.
One addition, it has been my observation that a dripping rifle is not a reliable rifle. Simply spraying stuff in the action, shaking it out, and dragging a filthy bore snake through once or twice, is not cleaning. When you clean, break down and scrub, follow SPQR's advice and get your picks out checking those nooks and crannies for build up. It can be very very hard if allowed to accumulate. It can keep your bolt from going far enough forward to get a reliable extractor grip, it can keep the extractor pushed away from the rim, and even push the case off to one side. All can lead to FTE issues, among other things.
Reassemble with as little lube as required. Good lube like Tetra for grease fans, CLP for liquid fans, and rem dry for spray on fans. I've had good luck with all three and my favorites change depending on my mood.
I am certain someone, somewhere, just started banging on their keyboard with greater wisdom. I am but a humble Shoot Boss, and those are my observations. ;D
YHJ
My usual cleaning is to go over the action with a pick (especially the bolt face, feed ramp, and extractor inlets, blow it out, wipe down with a Dexron dampened sock (because I'm out of Ed's Red and haven't gotten around to making another batch, yes, I'm cheap), and wipe off with a clean sock.
Bolt face and extractors were cleaned with a screwdriver Saturday at lunch without improvement
Saturday night it was given a thorough clean and lube by another IIT who has smithed for a living. From all descriptions, the problem persisted (I was at another line on Saturday and had a family priority on Sunday).
Failure mode was described as failure to extract an unfired round - thus the manual cycling as a test rather than firing.
Prior to sending it out as a loaner, I'd cleaned it, put about 200 rounds of federal automatch down range, and given it a lighter cleaning - just not that much there to worry about yet.
CCI had been my goto ammo - until I found the federal automatch gave me a little more accuracy at 2/3 the cost. Still have about 1k rounds of it left.
Looking at this post, I'm wondering if Dexron (synthetic transmission fluid) might have issues at 40f.
Transmission fluid should be good at resisting an increase in viscosity whether synthetic or not. I don't think its the fluid (unless there is too much as jake says). I wonder about part wear (unless you ARE the guy that got the bad batch of MiniMag :) ).
Quote from: Rafn on October 17, 2011, 11:11:48 PM
Looking at this post, I'm wondering if Dexron (synthetic transmission fluid) might have issues at 40f.
I doubt it. I've long considered ATF to be the goto lube for revolvers and never had an issue. I wonder about extractor wear. Checking my Marlin, it's filthy and has a good bit of accumulated fouling. Yet it ran the last 500 rounds without failure.
If your extractor tension strong?
Maye you should try a fresh box of MM?
YHJ
Got the loaners back - there was a bent recoil spring on the one that went south. Bent it back into usable trim, flipped 180 degrees (section that had bent is now inside the bolt), and will test without cleaning (looked damn near spotless) if I can run to the range this weekend. Unfortunately it's already below freezing most nights, and I've insulation to finish.