On many of those German examples, the chamber length if greater than 65mm(+/- 2.5mm I believe or was the line of demarcation 5mm?) was stamped on the face of the extractor. Tom McDevitt(passed in April 2009) had an Iver Johnson Sporting Goods Simson O/U but something was amiss with the ejectors. I'll have to attempt to dig up the images.

http://www.doublegunshop.com/forums/ubbthreads.php?ubb=showflat&Number=110240&page=1

Kind Regards,

Raimey
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