Well... here's the deal.
The RCBS Comp sizer uses a high expander ball, which is NOT available in the standard RCBS sizers - that's nice, but Forester uses the high expander ball in ALL of their sizing dies... no extra charge.
(The Redding standard sizers, both FL and Neck, SUCK!!)
On the seaters - the RCBS uses a poor copy of the original Vickerman design, copied (cheaply) when the Vickerman patent ran out.
In the Vickerman Seater, the sliding sleeve was an air gauge fit (less than 0.001" clearance).
The base of the sleeve was bored so the case neck went inside the sleeve. Plus the bore hole for the bullet was ~0.0015 over bullet size.
So alignment was absolute!!
They were expensive (about $175 in today's worthless dollars).
The RCBS sleeve is loose in the die body (it rattles), plus the base of the sleeve is just a cone, so alignment is approximate. Plus, the bore hole for the bullet is way over size.
So the bullet rattles in a sleeve, which rattles in the die body, that sits on top of the case with no alignment! /ubbthreads/images/graemlins/frown.gif
The Forster and Redding seaters use sleeves that have a complete cut chamber in them - there is no place for the bullet to go except straight into the neck - the same each time.
And I have owned all of the above (and more).
There is a company that has re-introduced the original Vickerman dies again for around $75 and up...
http://www.gmwvickerman.com/new_page_1.htm
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