https://thegreatmodel8.net/

Am I missing something here.
Please look at the Gun Broker listing and tell me if this listing it a bit curious.
As listed a M81 ser# 29666 30 cal. however no trade mark stamping or visible ser# on left side of receiver.
Also no mag spring or slot for one on left side of trigger plate.

Good catch! Probably 1912 M8 receiver with M81 trigger housing.