I weighed several pinfires today and since Aaron's 10 ga and my 10 ga. Richard Jeffery weighed in the lower 7 pound range, I expected other pinfires to be relatively light compared to British and European centerfires of the period. I did not find the other pinfires to be really light guns. Here's what I saw.
All French and Belgian guns had variations of the Lefaucheux action. I guess the extra light 10 ga. pinfires mentioned are not the standard.

Bissell [England] 8 gauge, 8 pounds 8 oz.
Harkom [Scotland[ 12 ga, 7 pounds 2 oz.
Sneider [USA] 12 ga, 7 pounds 14 oz.
French no name , high quality 16 ga, 6 pounds 6 oz.
Lefaucheux [Belgium/France] 16 ga. ,7 pounds 7 oz.
Le Page [Belgium/France] 16 ga. , 6 pounds 14 oz.
Claudin [Belgium/France]14 ga., 6 pounds 13 oz.
Belgian no name, 24 ga. ,6 pounds 7 oz.