I have a Marlin 30AS, 30-30 lever with a bushnell 4X mounted on ring bases so i can still use the factory sights at ranges under 75 yrds.

I have used this gun for years with just factory sights and have consistently dropped big whitetail bucks out to as far as 425 yrds, and as close as 10 yrds.

I find the grain of bullet makes a significant difference in the range capabilities of my rifle and generally opt for a 150gr bullet now for most situations, but will go up to a 170gr for stalking in thicker bush where I will not be shooting great distances but may need the extra mass to deal with obstructions like branches.

Ideally for my hunting, if I were to go strictly scope sights, I would opt for an adjustable power that tops out at 4.5X. I recommend a scope with good light gathering capabilities as it will assist your eye in focussing better on target in most light conditions.

Good luck and happy hunting!!!