stumpped

[HighKnob]

I was doing load development 7mmRM in a 700 Remington. I was getting at the top end of the load. Had shot 2 rounds of this load, had primers getting flat and bit of crater with a shiny spot on the brass base once in a whle. No shiny ring on the side of the brass. The third shot stuck the case. Had to knock the bolt handle up with my palm the last half inch, then it wouldn't extract. I hit the bolt with the heel of my hand a couple times and the bolt pulled from the rim. I checked the bolt and it looked fine. The primer in the case inside the chamber look very well also, flat primer with some crater. When i got home from the range i took a cleaning rod and inserted it down into the brass and tapped it and the bottom part of the brass came no trouble, just where they usually separate. I thought i would have a hard time getting the rest out, but just running down the cleaning rod again with a slotted end in to catch the case neck and the brass dropped right out. What i'm stumpped with is the case had a huge dent from below the shoulder to the edge of the case neck. What could have caused this. I sent a lot of rounds down in nearly 40 years and never saw this before.

 

[royinidaho]

If I read your post correctly the case came out in two pieces?

That would be head separation, or case failure.

It was most probably (and hopefully a well used case).

Check your other cases with a long sharp thing (very fine crocheting (sic) needle and check for a ring 'inside' the case just above the head.

There is along ago thread hear about your symptoms with out the head separation.

The long dents, if I remember correctly, occur when pressure on the out side of the case exceeds the internal case pressure. This could happen with case separation. Especially as indicated by the length of the dent you described.

Usually the dents don't go much below the shoulder.

Just my thoughts and I may be a bit off......

 

[HighKnob]

That makes all matters of sense, thanks for the reply. At least now i know and yes it was a well used case, just didn't have the normal ring that i could tell.

 

[woods]

The dents are very common with case head separations

When the case separates, the gas escapes into the chamber and escapes out the bore through the dent, at least that is the theory.

 

[HighKnob]

That pic is just like it. I guess what had me was it staying together at the start. All the case separations i've had in the past were 222 Remington and never had that dent. Thanks!