thebrassnuckles wrote:Ok, So any adjusting done on the taper crimp die is only to adjust the strength of the crimp, correct?
adjustments to the seat depth are done with the seating die, correct?
if i were to change what bullet I was loading, say from 275gr xpb to 240gr xtp all I would need to do is make sure the cannelure of each bullet is in the correct location for the crimp to grab onto, using only the seating die for this adjustment. correct?
if so, all i need to do to change loads is to adjust the seat depth.. all other are constant.
That pretty much sums it up, but it's like saying to go left or right, turn the steering wheel. To go forward press the gas. To stop, press the brake. "Now I understand how to drive." Don't take that in a bad way. I would be remiss if I didn't point out that there is more to reloading than just the mechanics of the equipment. I don't want Eric to have an anxiety attack.
Some of the nuance of reloading is more important with other calibers, but I personally feel we are challenged with this particular cartridge design in ways that emphasize a few settings and de-emphasize many of the more esoteric ones with more sophisticated cartridges.
As you adjust the taper crimp die downward, stop and measure that mouth edge OD frequently and when I say measure, I mean not too far down the cartridge. It's the very edge of the mouth that engages the lip of the chamber and that die is as it's name implies a
Taper crimp. Even .001 inches down the case will be wider than right at the edge. The way I do it is set my micrometer to .475 and lock it. I then position the crimped case mouth on the sharp edges of the micrometer and see if it can drop through, even the slightest bit. If it does, I don't go narrower on the crimp. If it doesn't, I advance the die a fraction of a turn and recrimp until that mouth edge just barely passes between the micrometer jaws. Do not check the diameter by placing the case in between the jaws and tightening the micrometer until it stops. It's too hard to maintain the insertion depth of the case in those jaws to only measure the very edge of the mouth, not farther down the case. If you don't have a micrometer, a caliper will have to do. Same procedure.
I have not slugged my chamber to see exactly where the lip measures out, but I determined a long time ago that .475 solidly engages the lip. I'm sure is varies from barrel to barrel and is less than .475, but unless you custom tune your cartridge to you chamber, you'll never know. All that leads up to this caveat. Always
Thunk test your first load to make sure it's safe in your chamber. If that
Thunk is not a distinct engagement, your case mouth may be too narrow for your chamber lip. Too wide only matters when it's wider than .480. You won't be able to get it in the chamber far enough to lock the lugs and chances are, if the mouth is that wide, you'll be hanging up at other points along the case which are diameter sensitive as well WRT the chamber dimensions.
Hoot