Yes, 20 gauge is the second most common gauge for shotguns in the last few decades.
I have just seen this set on gunbroker.com
a 20 gauge is a type of many shotguns but it is smaller than a 12 gauge but bigger that a 410. a 20 gauge is a good shotgun for all ages.
Over-under shotgun san marco
12 has a bigger bore.
These shotguns came in 20, 28, 16, And 12 gauge calibers
Crescent Fire Arms made millions of similar shotguns with over a hundred different trade names. I doubt if anyone has a good estimate, but there were a lot. 20 gauge will be harder to find than 12s.
Rifles are referred to by caliber. Shotguns are referred to by gauge.
100,000
20 gauge marlin ou 2 triggers
try: SAVAGE SHOTGUN.COM
75-100 yrs ago