I will start by saying that one of the coolest parts of turkey hunting is putting on my mask, gloves, leafy suit, etc, and looking like a big pile of weeds. Packing a shotgun in Realtree APG just adds to that.
But...
I've had several camo turkey guns. 835, SX2, etc, in camo. My last turkey gun was all black and my current one is all black. I haven't noticed a difference in my success. (I looked cooler with the other ones though)
Here's something to think about (don't actually try this). Imagine you're the turkey looking at a hunter with a camo shotgun pointed at you and a hunter with a black shotgun pointed at you. The only thing you are going to see is the black hole at the end of the barrel on both of them
rw