[Fatelvis]

I remember reading somebody smarter than me dictating "1/4 turn of a 7/8X14 die equals .00X" die movement" and such, but I cannot seem to find it. Can anyone refresh my memory? Thanks-

[jcwit]

Using math divide 1,000 by 14 the number of threads per inch. However because of tolerances in both threads it will vary.

[rikman]

I was taught divide 1 inch my 14 threads per inch.

so one turn equals= .0714"
1/4 turn = .0178"

That's why I went to mostly all competition seaters.

[jcwit]

Same thing, there are 1,000 thousands in 1 inch.

[Fatelvis]

Wow, that was easy! Thanks!

[medalguy]

When I'm setting up dies, I use a rule of thumb of 1 turn equals 60 thousandths, a quarter turn gives me 15 thousandths, then I start doing fine adjustments and use a micrometer.

[Fatelvis]

Ok, so #3 is mathmatically correct, but I suppose the "slop" in the threads probably account for the variance from your figures and his?

[rcmodel]

If you only partially loosen the die lock ring enough to allow turning the die body?

There is no "slop" in the threads.

1" = 1.000".
14 TPI = threads per inch.

1000 / 14 = .0714" per full turn.
1/8 turn = about .009".

It is nearly as accurate as a micrometer die unless you loosen the lock ring completely and let the die threads slop around in the press threads.

rc

[gspn]

Hey...there's not supposed to be any math on this site. :cuss:

[1SOW]

.0714 / 360 degs = inches per degree of rotation = (approx.).0002"

10 degrees of rotation would be (approx.)= .002"

SOOooo if you printed a stick-on circle with 36 equally spaced dots.
ANY Mark on the die could be used to change the die .002" accurately.
HALF a dot would yield .001" increments.
FIVE DOTS would= .010"

If I didn't screw up the arithmetic, this is workable and really kinda cool.

[WNTFW]

A dial indicator works too. You just need a consistent base and a place to measure on the die. Same goes for dial caliper.

[Captaingyro]

Although previous posters have given you the exact answer (71.4 thousandths per turn) I've always found it easier to remember 72. An added bonus is that 72 is divisible by just about everything (2, 3, 4, 6, 8, 9, 12) so you can usually get within a couple thousandths of the adjustment you need to make.

[jcwit]

Captain, never thought of that, excellant info!

[ranger335v]

Seater plug threads are MUCH finer than the 1-14 of the die body, surely no one tries to adjust bullet seating depth by screwing the body up and down. (Okay, nit pickers need not panic, I said seating, not crimping).

Die body adjustment is all we have for adjusting sizing, especially for FL sizing to match the chamber. If it weren't so potentially harmful it would be laffable to see many posts 'wisely' telling new guys to make sizer adjustments in "small changes like 1/4 or 1/2 turn" until they get the cases sized right. Goodness, that changes the shoulders in steps from about 18 to nearly 36 thousants; given that most bottleneck cartridges only have a range of about 6 thou, min to max, for headspace, those 'small changes' are massive!