Split cases
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NO,. IT IS NOT NORMAL.
However, it does happen. Cartridges fired in older rifles with oversize or neglected chambers can cause this. If there is a defect in the chamber, a split may happen. If it happens consistently with one rifle, then the rifle barrel / chamber should be suspect.
An overly long firing pin, or a sharp pointed firing pin can also cause a case rupture. Does the split originate where the firing pin hit the rim?
A common cause of this type of case failure is the case itself. While care is taken in manufacturing cartridges, it sometimes happens that the metal itself is at fault. A small foreign slag inclusion can weaken the case metal, or a small sharp piece of metal on a die can cause a small groove in the metal case. ( .22 cases are punched out of a metal strip, then formed to size. )
Even a production run of .22s can be faulty. Some brands (particularly cheap foreign ones) are not the same quality as domestic ones.
So, you have to look at a couple of things.
1. Does it happen with ALL BRANDS of ammo? If so, have a gunsmith check over the rifle. Make sure you take case samples with you.
2. Does it happen with only one Brand. If so, change to another one.
3. Does it happen frequently. If so, do NOT fire the rifle, take it to a gunsmith.
4. Has it happened only once or twice. If so, it is probably a faulty cartridge case itself, and not the rifle.
IT IS ALWAYS WISE TO WEAR SAFETY GLASSES WHEN FIRING A RIFLE.
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