Resizing with RCBS small-base

[madmosche]

With RCBS small-base 300 BLK dies touching the shellholder, I'm getting 15 thousandths shoulder pushback compared to fire-formed. Stupid question but can I back out the sizing die so it's not touching the shellholder to get the desired 5 thousandths resizing? Thanks

[20X11]

Yes you can.

[madmosche]

Thanks!

[rlandry6]

That may not get you sized all the way to the bottom of the case. At this point, the die itself is also suspect. Even RCBS and Redding turn out an occasional bad one.
I recommend that you order the slotted case gauge from Sheridan Engineering and find out where you really are with this.
Do some research before oedering any other case gauge. All will get you there on headspace, but some will not show if the case is sized correctly. Wilson case gauges are one that does not check for correct body sizing.

[madmosche]

What about the Lyman headspace gauge?

Nonetheless, any case gauge is going to be made from a reamer and your gun's chamber is made from a different reamer, they aren't necessarily the same. I'm measuring the headspace on my fire-formed brass and then resizing to push back the shoulder .003-.005 for an AR-15. Same thing I do with standard FL sizing dies for .223, except I went with the Small Base dies for 300 BLK as I plan to form cases from chopped-down 223.

[BJK]

There are others, but you could use this to return brass to spec' down to the rim. Then do what needs to be done with the sizing die.
http://casepro100.com/products.ydev

[dellet]

You can also use Redding completion shell holder.

They will allow full contact of the ram to the shell holder for consistent sizing, while giving .010” adjustment to the base to datum line.

A small base die is only needed if the brass was fired in a system that was over gassed. So may only be needed for converting brass, then no longer needed.