Wayne S
posted this
03 November 2010
RicinYakima wrote: Bill,
I think about it this way:
In the barrel the bullet has nothing on the front, just the open bore. It may (!) touch on a couple of lands and maybe the edge of one band. Then it gets 20,000+ psi applied only to the back end in 0.0001 second.
In the bump die, it is totally surrounded, either by the die or lube in the grease grooves. It has steady pressure of maybe 1000 psi applied over several seconds.
At least that is how I look at it.
Ric PLUS, the bump die should conform the nose to the same Dem. and angles as the weapon's chamber, there for it is supported on all sides and if not already engraving the rifleing it is guided into them supported on all sides, VS the bullet that has a jump from the case to the rifleings,