Hi Dean,
The folks at Simpson's list the book, new, for $ 125 on their web site. Go to the "Shop On Line" section, the "Book" tab, and on page 2, see item # BK-118 :
http://www.simpsonltd.com/
The 1906/24 W+F Bern should be internally "in the white" (up to a certain serial number) after which they were salt blued. I am away from my reference library, at the moment, and cannot give you the cut-over date...but if I recall...it happens around the same time/date when the "island" on the trigger plate went from 3/4 vertical height to full height...
Most of the Bern refinished pieces I have seen still have the interiors "in the white", from which I suspose Bern left the "white" intact when refinishing a piece. But some of the more skilled refinishers here in the USA and elsewhere can probably do a rust blue job while not touching the interior...so seeing an "in the white" frame is not always a 100% indication of true factory original finish uless other tell-tale signs (or lack of signs) are on the pistol as well.
I have seen some Waffenfabrik USA pieces (offered for sale as "original) that are salt blued and then carefully (but not thoroughly) polished on the inside surfaces...
I shoot Winchester .30 cal...with no troubles in my 2 - 30 cal. shooters.
Regards,
Pete... <img border="0" alt="[typing]" title="" src="graemlins/yltype.gif" />