Does your resizing speed affect the finished size?

[fatelvis]

I guess I could experiment and figure this out myself, but I wanted to ask you your findings. When running a sized case up into the die, if you stop and wait a few seconds at the top of stroke , does it affect the finish size of the case? I was just wondering if that was a variable that I did not take into account when sizing in regards to headspace. Thanks!

[StratsMan]

I think of it like follow-through... eg: I hold the sight picture after the pulling the trigger even though I know the bullet is gone, 'cuz if I don't then I will move too soon... Sometimes before the 'bang'... So I hold the press handle at the end of the stroke for a short second 'cuz if I don't then occasionally I will short stroke a case...

[Budzilla 19]

What he said! ^^^^^^^^^^^ I pause for a few seconds at the top of the stroke to make sure I have not short stroked one! I resize my 7 STW rounds a lot slower on the stroke than the rest of the rifle cartridges. I don't know why, maybe something in my head. Different strokes for different folks! ( sorry, I couldn't resist)!!!! Just my .02

[GRUMPA]

Brass has what I call "Spring Back" and will want to by nature want to expand just a little. Some of the conversions I do I size twice, do the initial sizing and lift up on the handle, but not enough to use the expander, and size again.

A lot has to do with just how much something is being sized.

[375RUGER]

Yes, i think it is related to how much work hardening the brass has experienced. Freshly annealed brass, not so much. Another variable that affects size/headspace is the amount of lube on the case.

[runfiverun]

I like to think of it as giving the brass time to finish flowing.

[JSnover]

Any difference will be slight but I found better consistency with a brief pause at the top of the stroke.

[EDG]

It does not really affect the diameter much but it can affect the head to datum length of the case.
Most of us have set up FL dies for forming bottle neck cases and found some of them difficult to chamber later. This is caused by variations in the speed of sizing, length of dwell time at the top of the stroke, amount of lube used and temper of the brass. These differences can be detected with the Hornady case gauge.

A good way to get rid of the variations is to double or triple size a case. This involves retracting the case from the die about 1/2" (do not pull the expander through the neck) rotate the case 120 degrees and size again slowly, then retract rotate and size again for the third time. Previously you would have had .001 to .002 variation in the length from the head to the shoulder datum. With the slow sizing using multiple strokes process you should have zero length variation along with better accuracy. If you set this length to exactly match your chamber you will get longer case life.

All that is happening is you are giving the brass a little more time to flow, bend and take a permanent set at exactly the same length.

[BUCKEYE BANDIT]

Thanks for asking that fatelvis.
45 years in collision repair and the hardest thing to get through a new tech's head was to give EVERYTHING a chance to move and settle.Like many above,I always stall at the top of the stroke just to be sure also.

I guess I could experiment and figure this out myself, but I wanted to ask you your findings. When running a sized case up into the die, if you stop and wait a few seconds at the top of stroke , does it affect the finish size of the case? I was just wondering if that was a variable that I did not take into account when sizing in regards to headspace. Thanks!

[bearcove]

Any difference will be slight but I found better consistency with a brief pause at the top of the stroke.

This is more important .CONSISTENT,same each time.

[RP]

Also a great time to drink some of your beer