7mm08 - that is a good rule of thumb.

Now for yrs I used Modified and hated it. I recently got back into duck hunting quite regular and took this gun to the pattern board as I struggled with it before. I found it was shooting low and off to the right. - no wonder!!
I modified the stock and on a whim I went to my Improved Cyclinder (IC) and now the gun is awesome. The IC choke tossed a far better pattern than my Modified.
I hunt mainly over decoys and use my decoys to aid me in distance to shoot. I never have my farthest decoy more than 35 yrds from me at any given point.
Hope this helps
JW