What eldeguello said...

You only want to set your case shoulder back far enough to allow for easy chambering- no more than .002"-.003" Using a FL, or evenworse, a Smallbase resizing die screwed all the way down will shorten the life of your brass.

Rifles that are within saami specs can vary significantly in chamber dimensions- it only has to be somewhere between a Go and No-go headspace guage.

I have swedish mausers that will swallow a SAAMI field guage for breakfast, but have no problems with brass seperating for a few reasons-

1. SAAMI specs are not the end-all-be-all of cartridge specs- they just allow American manufacterers to operate without being sued out of existance by making standardized ammunition and rifles.

2. Excess headspace has to be pretty excessive to be a real problem. After the first firing, the brass will stretch to fit the chamber- youget into trouble when you lean hard on your rockchucker to get the case back to SAAMI specs- the next firing will stretch te same bit of brass that has already been stretched, causing increased weakenss and in extreme cases, caseheadfailure. Just set the die up so it kisses the shoulder, then try chambering the brass with a stripped bolt- continue sizing it down until you can chamber it with minimal resistance.

3. The brass has a bit of springiness to it. When the hot brass expands to fill the chamber, it also shrinks back a little. This is why you can kneck size a case and still chamber it. Though the amont of stretching will eventually catch up and you will need to FL size it after firing a couple of times.