If I had a choice of the two weapons for a BG take down I'd choose the rifle every time!
Pistols are great for most SD situations! But if you want complete take down damage any high powered soft nosed bullet will decapitate at close range/ blow big nasty holes!
Now if you want rifle performance with out the High powered rifle round go with a pistol carbine/levergun! Same damage as a rifle with out the recoil!
Don't believe me talk to a Vet of WWII/Korea and ask them what a rifle round will do at close range! Ask them how good they were when they did CCQB! And that was with Ball ammo! Try soft nosed bullets!
Of course where talking about "Real Rifle" rounds of .30 Caliber!