I killed my first with a 20 gauge dove load when I was 9. 10 and 11 shot 20 gauge turkey loads, 12 on shot 12 gauge turkey loads. Like's been said already, never notice recoil when I've shot an animal.
So I scraped the whole idea of using pheasant loads. Check this out..... Who would have thought without doing some math. Federal Wing-Shok 20 Gauge 2 3/4 1 oz #5 Copper Plated Lead Pellet Count: 173 Muzzle Velocity: 1350 Foot Pounds of Recoil Energy: 28.6 HEVI-13 20 Gauge 3" 1-1/4 oz #7 Hevi-Shot Muzzle Velocity: 1090 Pellet Count: 348 Foot Pounds of Recoil Energy: 28.3
Hands down use the hevi load. The difference in recoil between the two loads is the velocity but with the increase in pellet weight of the hevi will offset the extra velocity of the lead load, plus the hevi load had a better pellet count. Looks like you've found your sons turkey load!
You're better off without a copper coating also, copper isn't as dense and lead and therefore doesn't penetrate as well. :D