Not trying to be agrumentative and I state this respectively, but I strongly disagree with this statement.

I would advise not putting a "cheap" scope on any gun that you plan on hunting game with. Cheap scopes will fail, especially on a hard kicking slug gun. I work too hard and my time in the woods is too valuable to worry about whether my equipment is still working properly. Nothing is more sickening that working all season to get one shot, one opportunity, to take the buck you have been chasing all season - only to miss because your "cheap" equipment fails you.

The difference between "shotgun" scopes and "rifle" scopes is magnification and parallax settings. For shotgun scopes (typically less magnification than 3-9) parallax is typically factory-set at 50 or 75 yards. Rifle scopes (standard 3-9 type scopes) have parallax set at 100 yards or, for those with higher degrees of magnification than 3-9, parallax is adjustable by turning the objective bell and changing the focal point of the image to match the plane of the retical.

I would suggest something like a Nikon Buckmaster, Bushnell 3200, Burris Fullfield II in 2-7 power. These can be bought for around $200.00 - 250.00 new or much less used. Look on ebay - I have several scopes I bought used off ebay and have been very satisfied. In general you are much better off with a good used scope than a cheap new one. In many cases the lifetime warranty transfers to the new owner. If not, you still have a better, clearer scope that is less likely to fail than the cheap one.

I have a Bushnell trophy 1.75 X 4 on my Mossberg 835 turkey gun. That gun kicks pretty hard, but that scope has held up well so far. I don't shoot that gun but 3-4 times a season, so it isn't taking a lot of punishment. I wouldn't be suprised if the scope fails before I can get it replaced with the Eotech holosight that I am saving for.

Remember - you get what you pay for in optics.