Mosin KB

[DevsAdvocate 112]

http://www.thefirearmblog.com/blog/2011/03/22/mosin-nagant-kaboom/

 

Guy's Mosin cracked a receiver at the range.

[Malsua 1,422]

I've always wondered if the hex receivers were weaker. Points and edges are fail points on metals subject to stress. One of the guys I worked for who built 1000+ hp race motors taught me that flashing, points and edges on anything on the bottom end of an engine was a weak spot. He'd go over everything with a file and smooth it all down and sand it. Apparently it focuses the stress on these areas where as something rounded will not.

[Dan 177]

I have to drop the ole 'Could have been much worse' adage. Crazy how it just split like that. I guess we have to remember that these are 70+ year old technology and built in a hurry by the millions. Defects are bound to occur. That being said I guess it could have been the ammo as well.

[siderman 1,139]

Interesting. I'd have thought the weakness would run parallel with the receiver not perpindicular. I'm also wondering if the crack in the stock is a tell of a past implosion that faulted the receiver at some point.Whatever, odds are with so many of them gotta be defects somewhere.

[junkmanted 54]

Hey the barrel is still good

 

There was 1 for sale on gunbroker about 6 months ago with a crack

[Maksim 1,504]

Wondering if it was the gun, or perhaps an overly hot charge. It is quite interesting though that the receiver split straight down the middle. First I have seen it on a Mosin.

[Krdshrk 3,878]

I've always wondered if the hex receivers were weaker. Points and edges are fail points on metals subject to stress.

 

Yes but it didn't break at one of the hex edges.... it broke smack dab in the middle!

[Babaganoosh 192]

The gun was probably used like a damn crowbar once or was stressed at that point somehow (someone leaning on it or mabe it fell over a few times, hell maybe it was actually used and bayonetted a few people. Something probably put a lot of stress on it at that point at some or multiple times and it finally went.

[hd2000fxdl 422]

By the looks of the pictures, it has been failing for quite some time, this wasn't a one time thing. Yes it could have been a hot load that finally made the crack, but it was bound to happen sooner or later no matter what ammo was being used. You can tell all this by looking at the picture where there is the clean crack on one end, and then you can see the old crack that has been happening for some time.

 

I really wouldn't be too concerned about any out there or the 2 I am waiting getting in that we have been talking about in the other thread, but I would take some extra time to inspect that area a little closer. Seems like this may have been able to be seen from the inside, or at least felt with a curved pick, like the kind you see at the dentist office. Probably too small an area for a cheap borescope to get in. Might see if the x-ray machines used to check welds might also be a good idea for one that may be questionable.

 

Just thinking out loud a little.

 

Harry

[usnmars 136]

dip it in a jar of gasoline. wipe off the excess. Immediately look at the receiver. if there is a crack there will be gas on the crack. while the rest of the receiver is dry, this is because the gas got into the crack and is now weeping out.

 

 

Sorry for bad grammar, I am on my ipod