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Posted: 4/23/2005 11:07:00 AM EDT
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Took my newest build out to the range today and came up with a pretty big problem. After shot number 5, FtF. It takes all my energy just to pull the CH back, but then locks up properly. No firing pin marks in bullet, no damage to bullet anywhere. Reload. Shoots one round, same thing happens. I took it home and cleaned it, it fired about 4 rounds and same problem started all over again. Any thoughts? Technical Specs: Bushy upper and lower LMT bolt group and CH recon barrell originaly from Denny/GTS (mid length, with RRA gas tube) Vltor Stock, std weight buffer |
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The ammo getting jammed is unfired rounds. I was shooting a mix of federal and winchester 55 grains. Both from the same lots i normally shoot with no problems. Buffer and tube are in good order, nothing strange there. I have to edit my original post too, the barrel is from Denny (I got it off the EE from somebody else) and was supposed to come with a fitted bolt. I just realized that for some reason I didn't get that.....gotta make me a call tomorrow.... anyways I suppose the chamber could be out of spec, although i have no way of checking at the moment. Tomorrow I'm gonna try my bushy bolt group and then my Colt group and see what happens. |
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You can check your chamber by breaking the lower up by taking the rear pin out, removing the bolt, and manually inserting a few unfired rounds, they should easily come out with a ram rod. Yes you can use a cleaning rod. Things to check: Buffer retaining pin is actually held in and the buffer tube is holding it in place. Depress the retaining pin with your finger to insure it is moving. The buffer tube should be up against the buffer retaining pin but not stopping it from moving. The buffer should move easily back and fourth. The reason the guys keep posting this is this is the usual problem with a new build and stuck bolts that don't go all the way forward. This should be obvious if you try to break the rifle open for the bolt will be partially in the buffer and won't easily. Check the magazine height but cycling without firing rounds by pulling the chargining handle back and releasing numerous times. This also shows no buffer issues but also if it works fine then leads you to the gas tube or trigger assembly. This also checks the freed ramp but that doesn't appear to be your problem. If the magazine height is too high this will make the bolt hard to move and scoring the upper round in the mag by putting a scrape mark on it. Clean you gas tube with pipe cleaner. I don't think this has anything to do with your problem since you stated its hard to pull back with the charging handle but never a bad ide to rule it out. Check trigger assembly works while rifle open dry fire. Hammer should go forward with a click and then you can easily reset the hammer back with your finger. This simulates the bolt movement. Check bolt that the gear moves easily and the firing pin moves. Gear fit shoudl be in the down position while inserting into the rifle. Most simply sling but some require a little help but it should move with no prolems. Now that I have covered the most common mechanical issues, here's the most likely "OH SHIT " issue. Did you mix CLP and another type oil? The damn mixture sets up like permatex glue. Never assume anyone used the same oil that you do. Tj |
On the rounds that stuck (or that you had to work hard to open the action to remove), are you sure there are NO marks on them? This is critical, since something gummed up in the chamber should leave a mark, like a scratch or gouge, or even some sort of gunk on the case. |
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Victory is mine! Thanks for all the input guys! The problem was with the bolt/carrier...although I'm not sure why. I replaced the LMT group with a Colt and it worked great. Then the Colt I took the bolt out of worked great with the LMT bolt i was having trouble with.....very strange. But everything works great now and I've added another black(and green and brown) rifle to my collection! |
Yep you are right that is strange. Almost sounds like some machine tolerances were slightly off but mating to a worn part it works fine. Glad it worked out for you. Tj |
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