Thanks, all for your replies, and a special thanks to you, Albert !
Mr. Stewart at the BATF can be reached at Tele. No. (202) 927-8320.
I have described the pistol in question which most likely will be ruled an antique that uses a 7.5 mm ammo. This ammo is not even sold in Switzerland anymore.
He will advise me tomorrow.
Regards and thanks, again...
Pete... <img border="0" alt="[typing]" title="" src="graemlins/yltype.gif" />