Here's a couple of quail/pheasant guns. I stick to the ubiquitous 12 gauge. I mostly hunt pheasant in KS and consider quail as a bonus bird.
1. Dickson RA from 1898; weighs about 6 lbs 4oz. Of course you need a Gordon to go along on the hunt.
2. A 12 gauge lighter than a typical 20 gauge at 5 lbs 8 oz. It works fine on pheasant or quail. A 2" H&H.
Ken