20ga 3" VERSUS 12ga 2 3/4"?

[sswv]

a little bored tonight so I got to thinking after a conversation with an older fellow that hunts with me sometimes.  lets say both (20ga 3" & 12ga 2 3/4") use the same brand and size shot as well as same length barrels. will a 20ga 3" hold up to a 12ga 2 3/4" at let's say 40 yards?  I guess I could go pattern them myself but thought I'd throw it out here.

thanks in advance

[daddyduke]

Tried this with 2 Remington 870s. Same choke brand, barrel length, brand of shells, shot size and amount of shot. 3" 20 gauge had tighter pattern at 40 than 2 3/4 12 gauge. At 20 & 30 yards 12 gauge had a very nice pattern!

[Tom Foolery]

My 20 gauge with 3" shells out patterns 2 3/4" from my 12.