Is severe underloading an issue?

Bigbubba

Bigbubba

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Ok so today I saw a bolt action rifle (6mm I think) that had a big chunk of the stock missing between the trigger guard and the bolt, the stock was cracked on the opposite side, there was a split in the receiver across the top just behind the chamber.

The shooter was there, he was giving the rifle to a guy to use in his safety training class. He got a concussion when the incident occurred.

He said he was new to rifle reloading (but experienced pistol loader) and the data he had said to start at 10% LESS than the MINIMUM load. (not 10% < max) So he is 100% sure he started at 10% < Min load. I have never seen any data that said that.

Assuming that he did that, has anyone ever heard of such a light load causing such catastropic failure?
Thanks for your input
 
First thing to come to mind is SEE, however rare it might be, it exists. If he actually loaded 10% below the minimum. Why wouldn't he understand the word minimum? If you can load lower than that, it wouldn't be the minimum would it?
 
Good rifle for a safety training course. Read the instructions, ask if you aren't sure. Wear eye protection.

"http://www.accuratepowder.com/faq/
The GOLDEN RULE of reloading is to always to begin at the recommended START load, which is between -10% below the MAXIMUM load for most Rifle calibers and up to 15% below for certain handgun calibers. The 1st and foremost reason is SAFETY:
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Huh, never heard of underloading being an issue before, I just assumed that it would presumably not be able to cycle semiauto and at extreme lows the bullet would get stuck in the barrel or hit the ground ten feet away. The more you know.
 
Probably pistol powder in the bottom/blind spot of his charge thrower.When he topped it off with rifle powder his first charge or 2 would be a lethal mix of pistol and rifle powder.
 
FIrst shot might have stuck a bullet in the barrel.

Too little powder can let all the powder sit on the side of the case, so it ignites too fast, causing high pressure. In theory, as I've never done it myself.
 
Cleftwynd said:
Don't all primers detonate all powders?
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nope , it is a very rapid burn ..... i beleive black powder detonates , and smokeless just burns rapidly

the spark plugs in a engine cause the fuel to burn rapidly .

but if the compresion is too high for the gasoline used you will get detonation .

when the fuel spontaneously combusts it creates 2 wave fronts , one from the sparkplug , and the other from the spontaneous event ( generally a hotspot in the head ) . when the 2 wave fronts collide , it causes a pressure spike and some very nasty noise in the engine .

something similar happens when using light charges of slow burning powder .
 
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I have seen light loads in manuals, it seems to me that they were small charges of fast powder, never small charges of slow powder. Lucky the fellow survived anyway, when the shrapnel is flying things could go much worse.
 
For those loading cast bullets it's quite common to load reduced loads well below the stated minimums. As long as you're above a 50% reduction you're supposedly safe. It's possible this guy missed loading powder into a cartridge and the primer alone lodged a bullet in the barrel. The next round did the damage.
 
SEE in small arms cartridges is a myth and IMO a scapegoat for people who fucc
up and can't admit it. If you disagree go tell the technicians at Speer/ATK/CCI they are wrong. Most likely cause is wrong powder or a lodged bullet as has been mentioned several times.
 
Everything I've read about SEE is that it happens ONLY when less than 50% of the available space for powder is used, and only with slow powders. Now I can't think of one slow powder that would be suitable for a 6mm that even a 10% reduction in min charge would reduce it to less than 1/2 full. I believe in the SEE theory, but I'm thinking in this case there must be a different explanation. These events are, from what I've read, experienced in large capacity magnum cases, with dramatically reduced charges of powder with burn rates of H4831 and slower. Most of these events, where the credability of the loader/shooter was very good, occurred using, very specifically, H4831. Ackley did a lot of research on this and, although he could not reproduce it, he came to the conclusion it did exist. This happened mostly in the 50s and 60s after the war and a lot more people took up loading, H4831 was cheap as dirt and a lot of guys tried to use it for all shooting needs. So you had guys shooting 30-06 and larger cases and wanting to do everything from subsonic to full blown loads and trying to use the extra cheap surplus H4831 for it all.
 
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