Firearm damage from high pressure rounds

Leeper said:
I can only speak to what I have seen and what I have seen is rifle actions which have deformed lugs and set back locking lug seats. This is not on old 98 Mausers and Springfields but on modern bolt action (and one lever action) rifles. These rifles were not damaged by the firing of a badly over-loaded round but by the continued use of load which were just a little too hot. Most were magnum cartridges though some were .473 diameter. Actions which were damaged in this way included Browning A-bolt, Browning BLR, Sako AV, Winchester Model 70 (post-64), FN Mauser, and Weatherby MKV. In all cases, the owners loaded them too hot and ignored warnings from people who knew better.
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Question because I like to learn.
Would a person notice changes in their brass after the deformation had happened? I’m guessing if things are moving within the action itself, signs should be showing up in the brass.
 
I can add one more type of firearm damage from hot handloads.
Old Parker Hale rifles built on Mauser actions had a very slender barrel contour over the chamber. My West Kootenay gunsmith friend had several magnum calibre rifles, 300 Win. Mag. in particular, that had swollen chambers and hard extraction from repeatedly shooting overpressure loads.
It is impossible to get something for nothing out of ballistics. Case capacity dictates what is possible, with safe pressures, out of a particular bore diameter. You cannot get 7 mm Rem Mag performance out of a 7x57.
Cartridge brass is the weak link, and cartridge cases are occasionally known to fail. Why push the limits with you hands and eyes at stake ?
 
Shooter ----/ said:
Question because I like to learn.
Would a person notice changes in their brass after the deformation had happened? I’m guessing if things are moving within the action itself, signs should be showing up in the brass.
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If the lugs are yielding, eventually you will have head space issues. This can be indicated in the brass by excessive case stretch, flattening of the head stamp, primer blow out, and in the worst case, case head separation.
 
Cameron SS said:
If the lugs are yielding, eventually you will have head space issues. This can be indicated in the brass by excessive case stretch, flattening of the head stamp, primer blow out, and in the worst case, case head separation.
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That is my guess as well. I am hoping to see a response mainly from Leeper or maybe even Guntech on the issue.
 
Originally Posted by Cameron
If the lugs are yielding, eventually you will have head space issues. This can be indicated in the brass by excessive case stretch, flattening of the head stamp, primer blow out, and in the worst case, case head separation.
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Shooter ----/ said:
That is my guess as well. I am hoping to see a response mainly from Leeper or maybe even Guntech on the issue.
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I have seen a few where the lugs have set back a considerable amount. (Mauser 98's) Of course this causes excessive headspace but if the brass is fresh it absorbs this stretching... the big problem is getting the bolt open as the lugs are settled back in the deformed lug recess and to open the bolt the lugs have to be forced ahead even tighter on the brass to get by the set back. Even the dullest realize something is wrong with the extremely hard to open bolt.
 
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These were loads which would result in loose primer pockets after three or four firings. There were ejector marks on the brass. Case head expansion was probably around.001" per firing. Because the chambers were smooth, extraction was OK. Only on the mauser actioned rifles did setback produce the situation where the bolt became difficult to open.
If you can't post personal information on your profile, what the hell is it there for? Perhaps we should confined our posts to non-gun-related issues like advanced weaving techniques (I have a lot to learn in this area) rather than gunsmithing.
 
If yielding has occurred the rifle is pretty much f'd. That's why the loading manuals all state to start low and work up carefully in small increments and watch for signs of over-pressure. Even then the signs aren't always interpreted correctly by certain types so yielding could have already been happening.

The pitfalls of buying a used rifle that's been handloaded. No way of knowing upon cursory examination. :eek:
 
Leeper said:
If you can't post personal information on your profile, what the hell is it there for? Perhaps we should confined our posts to non-gun-related issues like advanced weaving techniques (I have a lot to learn in this area) rather than gunsmithing.
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I agree... but somehow CGN feels personal information in "My Profile" is a security risk to CGN. They have not defined exactly what information I can or can not post... just that I can not post extensive and exact personal information. I assume I would have to post a fictional biography and a fictional name and a fictional email and mailing address.
 
I can probably help with that fake bio if you like. Let's see, young, handsome, thought about the priesthood but weren't sure about the celibacy requirement. Like long walks on the beach and have watched "Pretty Woman" 17 times. I can probably come up with more; with CGN's approval, of course. :)
 
I thought possibly I could get back in the EE sooner but I have been told the earliest I can apply to get back in is March 4th and then wait 10 days minimum for approval.... so that is effectively 70 days ban from the EE for having 'personal information' in my profile (for over a decade)... the profile CGN asks for us to fill out...

My recommendation is to not fill out your profile at all...
 
I had an HVA FN98 in 30'06 that was in pretty decent condition, put a few rounds through it without issue. Took it in to be rebarreled to 9.3x62 and the Smith noticed pretty significant receiver lug setback. He figured either a soft receiver or someone previous to me owning it liked overloading.
I remember reading the psi at the lugs was not very high...5%-10% of the cartridge psi load.
 
If I want a faster bullet I get a bigger caliber . I just don't see the value in exceeding recommended tables and don't want the risk. I do recall a guy at the range with his hot loads getting a rubber mallet from the car to beat the bolt open.
 
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