how do you case prep? with what equipment?

[Timberwolf]

For precision rifle:
Match Prep (cases virgin to 4 reloadings):
Clean, F/L size, trim, chaffer, debur (I only trim, chafer and debur on the initial prep), clean again, clean out primer pockets, uniform flash hole (virgin or 1st relaoding only), weigh cases and seperate, the prime.

Practice and/or Range Fodder (cases with 4+ reloadings):
Same as above except I don't weigh and seperate and I usually neck size.

[ar15barrels]

The best is using the shoulder to reference length for trimming...like the Giraud, Gracey or possum hollow trimmers.

Why is it best to use the shoulder?
Shoulder lengths are not always consistent.
Measure through a couple dozen sized or fired rounds with a case comparator.

[rksimple]

Why is it best to use the shoulder?
Shoulder lengths are not always consistent.
Measure through a couple dozen sized or fired rounds with a case comparator.

Because its the only other reference point (besides the base) that controls how the round is chambered. You know this. Didn't you hash it out with Doug Giraud himself? Its the distance from the shoulder to the leade that determines if you have to trim at all, not the base to the leade. Using the base to determine OAL can/will also lead to inconsistent neck lengths causing variances in neck tension...or so they say. I'm not good enough nor have a rifle capable of noticing such differences.

If a crimp is to be applied, trimming using the base as the reference point is better, as the die and shellholder use same.

[ar15barrels]

If a crimp is to be applied, trimming using the base as the reference point is better, as the die and shellholder use same.

Perhaps we can agree that there is not ONE specific way that's better?

"It's best to trim with reference to the cartridge case head when bullets will be crimped
and best to trim with reference to the shoulder when they will not be crimped."

That's probably the best way to be answer the question.

[rksimple]

Perhaps we can agree that there is not ONE specific way that's better?

"It's best to trim with reference to the cartridge case head when bullets will be crimped
and best to trim with reference to the shoulder when they will not be crimped."

That's probably the best way to be answer the question.

Oh of course. For accuracy, however theoretical it may be, using the shoulder is the best. For everything else, it doesn't really matter as long as the crimp is even and it chambers.