.22 Grooved Receivers
The scope mount post by 338magnut got me wondering who started the .22 grooved receivers. My vote would be Mossberg: The 146B that I bought in 1951 was grooved. The 152 was brought out in 1948 and that was grooved, also. The 151M came out in 1946 and had grooves, too, but I can't find any references that state Mossberg started the grooves. One would have thought there would have been a patent involved but maybe it wasn't an innovative enough idea to be eligible for a patent. Anybody know of anything earlier than 1946?