Im between .22's but a family friend needs help with gophers, I should be fine with my 12 gauge, #6 shot and a full choke for about 30 yards right?
I notice you're in Southern Ontario? If that's the case and your "family friend" is in Southern Ontario too...then there is ZERO chance it's gophers (Richardson's ground squirrels) you'll be aiming at. What your family friend in S. Ontario has is a groundhog problem, and neither a .22 or a 12ga. with #6 shot @ 30 yards is the right medicine.
ALBERTA Gopher (unzipped with a 17HMR)
ALBERTA Gopher peppered with #7-1/2 shot, no choke, from about 30' away
Groundhog smacked in the boiler from almost 200 yards with a .223, his lunch still hanging in his yapper
As you can see, a gopher and a groundhog are very different creatures size-wise. Neither are overly clever, but groundhogs are geniuses compared to gophers. Now, before anyone says ".22s are great for groundhogs"...I've shot them with 22LR, 22WMR, 17HMR, .204 Ruger, .223, .243, .270, and both 12ga and 20ga shotguns. They ALL get the job done provided shot placement and distance are both factored in. I could expand on that.

Anyhow, if indeed it IS groundhogs you're after, the very BEST shotgun ammo I've used on them is the Hornady Varmint Express 12ga. http://www.hornady.com/store/12-Ga-VX-4-Buckshot/ Where I shoot them, it's typically too flat/dry/hard to risk using a slug (which I'd prefer), but 00 Buck doesn't pattern worth a darn at any real distance. This Hornady stuff~wow.
Anyhow, good luck...I'd be curious if it IS gophers, or, groundhogs. I've heard lots of people call groundhogs gophers here in Ontario, and as a huge fan of shooting both of them...I'm very opinionated.
What self-respecting "GunNut" is ever "between 22s"? Unimaginable!
^glad somebody else noticed.
