What the hell?

skoal3

New member
I have another post about this for anyone interested but I went out today to try out some new factory ammo and everything was going fine with the usual Remington core lokts and a couple Federal rounds so I tried out the Hornady Superformance SST, the newest contender for deer season. This is a Thompson Center Dimension in 7mm08, by the way.first one went bang, second one, click. I cocked the bolt again and click, did that about 3 more times and I finally took that round out and hid it behind a tree, the primer was struck on the first attempt but it failed to fire. Had the same problem on the next one or two rounds but I cocked the rifle again and they went off the second time. This is a new rifle and I know nothing is perfect but I hate to blame the gun, the firing pin hits the primer, what more could you ask for? I compared the rounds to others that did fire and it looked like it was struck plenty hard, the dent appeared the same. I also hate to blame the ammo, with the SSTs I had 4 shots under 2 inches at 200 yards, not sure how I managed to pull that off. I'm sure there is an issue with the gun/bolt/firing pin but I don't want to believe it, not until after hunting season anyway, then I can send it back to the factory. The question I have now is could it be the ammo? I know this is highly unlikely but I've had 4 or 5 rounds now fail to fire and they have all been Hornady, first was the American Whitetail and now the Superformance. I'm sure the people at Hornady have ammunition figured out by now but I kinda find it strange, I've shot over 200 rounds with this rifle and the only time I have an issue, it seems, is with Hornady rounds. I'm not trying to bad mouth Hornady at all, with the accuracy I get I love their products but what the hell is going on. Come on guys make me feel better.
 
The size of the group doesn't matter much if the gun doesn't go off.

The fault might not totally be with the ammo. If a firing pin spring is on the edge, one brand of ammo or primer might fire fine, and another brand with a harder primer might not.

The first question is whether you have made, or have had made, any changes to the gun. If not, and given that all the ammo involved is factory, it seems to me that the problem may well be the ammo. The fault may be hard primers, faulty primers, or even out of spec cases that are cushioning the cartridges. If the gun is new, why not take it back to the shop where you bought it and have them check it out. But going hunting with a gun that may have a problem, using ammunition that fails to fire, just might not be the best way to get a nice trophy rack.

Jim
 
I realize that accuracy makes no difference if it won't go bang and that is gonna make me just a little irritated if I have an animal in the crosshairs and all I get is a click. I was wondering about exactly what you said though, case size, maybe the rim is a little narrow or the neck a slightly steeper angle, possibly allowing the whole round to move forward a little when the firing pin strikes it. If that is the case though it doesn't go far, every round has been pulled out by the extractor. I guess the extractor could be out of spec., I'm not sure what to think and I know there is a lot of smart people on here so hopefully I can get a tip or two. One of my neighbors happens to be a retired gunsmith so I need to get over there and let him take a look at it. Oh and also, no I have not done anything to the gun, well nothing major. After the first couple misfires I took the bolt apart, cleaned it and polished all the blueing off the firing pin, I realize that will probably be enough for Thompson to void the warranty which is fine with me ,new bolts are cheap enough and I might order one just to hopefully fix the problem but I haven't done anything to cause this. I started having problems before I started fiddling.
 
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When you took the bolt apart was it oily and dirty? Do you oil the bore and store it upright? If you answered yes to both those, that is your problem. Clean the bolt with mineral spirits, let it dry and put it together dry. When you oil the barrel just barely get the patch damp with oil.

Had a similar situation with a friends gun. This cured it. Could be the primers but more likely the firing pin is dirty or the spring is a little weak.
 
I have seen this problem a couple of times.

Once, it was a gummed up bolt ...... disassembly and a thorough cleaning cured it.

The other time it was handloads that were put together poorly with primers that were manufactured ...... probably during the Johnson Aministration or thereabouts ...... and seated far too deeply. Lots misfires outa that box.
 
I actually don't do either. When I took it apart it had a little bit of grease in it from the factory but not very much, I don't think it would have caused it and obviously didn't because I cleaned it out and didn't put any back in, I just took a wet patch and rubbed it on the parts of the firing pin that come in contact with the bolt. I usually store them muzzle down but this one has been sitting flat, in a case by the couch with little to no oil in the barrel, I've been shooting it almost every weekend so it might not get a through cleaning when I'm done. I thank you for your help though, also to take the bolt apart you have to remove it from the gun and uncock it so you have to recock it to put it back in, I know you don't have much leverage just trying to twist the end of it but I have a hell of a time trying to do it every time, that spring sure feels stiff to me. It may not be though, it is a lot harder to cock than my model 70 but not terribly hard. A friend thought the firing pin may be bent a little kind of putting it in a bind? I don't see anything obvious by looking at it and still, only with the Hornady ammo so far. Thanks again for the help.
 
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