mandrel for case necks...can somebody please explain

[milboltnut]

excellent direction. So if you wanted to bump the shoulder back a hair so the cartridge will chamber, you can use a tad shorter shellholder or just adjust the sizing die 1/16 turn lower incrementally until it chambers with no resistence. I think I've got it...Thanks a bunch.
I opened the box for my new t7 press. Looks well made
Looks like 10mm mounting holes. Ill pick up the hardware tomorrow morning and get it set up.

instead of adjusting your die, you can use a feeller gauges between the die and the shell holder.

 

[Alex Wheeler]

Far too much of what gets repeated about shooting and reloading is just someone's theory on what "should" be best, no real testing done. Do not follow any of this stuff blindly. Try different things yourself and let the target be the judge.

In my experiance, I have been able to achieve 1/3 moa or better groups at 1k out of every hunting rifle I have tuned using bushing dies without expanders and no turn necks. Thats with unsorted components and very basic loading practices. The TUNE is what matters the most. The right primer, powder, bullet, neck tension, seating depth, and charge. Thats got to be dead nuts for accuracy at long range.

 

[Tparrish]

What Mr Wheeler said.

 

[QuietTexan]

Half-ten thou, .00005" or half-thou, .0005?

Yeah I was off a zero on that, it was late. Half-thou and whole-thou. The point was you get an interspaced step per interval with the mandrels, which lets you move the neck up less than you previously did down with the bushing.

I'm putting a plan together to play around with my annealer; first goal is can I manually adjust the AMP code to make cases spring back different consistently, second is can I push a mandrel in and out without the neck moving permanently. Then see if any of that makes a change in seating pressure consistency.

Then see if any of that shows up on the target. I've been needing to make a trip to Raton, this seems like as good an excuse as any to go back.

 

[RidgeTop]

When you full size or neck size the die leaves the neck i.d. a little less that what you need. When you pull the expander back out, which is slightly lubed, it will be ever so slightly over the desired i.d. and then the brass will spring back slightly to be the desired neck diameter. Tumble clean and chamfer and you are ready.
You can get carbide expander or regular steel and some in a little over or under to your liking. I load the bullets dry with .001 to .002 hold.