Which is the better gun? 12 gauge or 20 gauge?

Both are well proven, but my vote would goto the 20ga.

These days the 20ga slug ammo has come a long way, it shoots flatter & tighter groups then the 12ga. less recoil which helps in accuracy, today's 20ga will take down deer/black bear without issues. If you're in the market for a new dedicated slug gun I would opt for the SAVAGE 220

Can't argue with any of that.

Either will do the job. The 20 should do it with a little less recoil.

-Jake

Do you have either with a smooth barrel? Got my first deer with 20 ga slug. I bought a 12, to hunt in a shotgun zone, but never discharged it in anger.

http://garage.grumpysperformance.com...-hunting.2722/

I am a 20 gauge fan.
Maybe I'm too sensitive to the blast, but I don't like how loud the 12 gauge is when fired without hearing protection while hunting.
The 12 gauge slugs also produce more felt recoil if not wearing a jacket to help pad the shoulder when shooting.slugs at the range.
When I hunted with a 20 ga, smooth bore, I used the Brenneke 20 ga. 2 3/4" magnum slugs without any problems and they produced good results on deer.
When I went to a 20 ga. rifled barrel, the Winchester BRI sabot slugs also performed admirably.
Here's photos of a 20 ga. BRI slug that traveled diagonally from a quartering shot through a large deer and was found on the far side under the hide.
The slug expanded from the original .40 caliber to about .65 caliber.
While the 20 ga. may be preferable to me, that doesn't mean that it's better for everyone.
I can imagine situations where a 12 ga. slug gun would offer some advantages.
But its disadvantages are the reasons why I'll always stick with a 20 ga. slug gun.