I am reposting this in this forum to hopefully get some more answers so if you could give me your opinions .I bought my wife a H AND R pardner pump 20 guage. Has 21 inch barrel and is smooth bore and has a modified chocke. It is drilled and tapped for a scope. Has anybody ever used a smooth bore for deer hunting and if so whats the max range you think it would hit good and what ammo is best for this situation?

i"ve heard of people sighting them in @ 100 yrds but i think myself would sight in in @75 yrds using foster style slugs in a smooth bore.
again it would also depend what you are hunting in / open field/ heavy brush & etc

may dad has shot deer at 100 yds with a smooth bore. anywhere on 75-100 depending on how much you practice. I think we have had good results with federal and remington rifled slugs.

i disagree... i think 50 yards is the best for a smooth bore 20 ga shooting buck shot. can ya shoot it 100 yards? sure...but i wouldnt.

I used to hunt with a smooth bore using federal rifled slugs and sighted it in at 100 yards.

Many years ago(40+) I hunted with a 12 ga. smooth bore, using 2 3/4" shells and a rifled slug. I had very good results at a 75 yard +/- limit. I do not recall ever taking a shot past about that distance. As far as best ammo? You'll need to try a few to determine which will group the best.

The setup you describe would have the scope mounted to the receiver, as opposed to the barrel. The barrel and receiver are not really locked together precisely and the barrel can move a bit between shots. This will drive you crazy when sighting in if you are expecting much accuracy. Some guns are better than others though. To minimize movement of the barrel, you need to tighten (but not overtighten) the barrel nut. A friend found he needed to use vice grips and a rag over the nut to get it tight enough, but I don't recommend that.

Also, realize that even if you're able to get the gun tight, 20 ga rifled slugs are about a 75-100 yd proposition anyway. If you find a slug that will give even 6" groups at 100, that's good enough for deer. Sight in at 50 yds to minimize the effects of wind. You'll want the group about an inch or two high at 50.

You do have the option of getting a smoothbore barrel with rifle sights. This will allow you to use rifled slugs which are far cheaper than sabots. With my smoothbore Mossberg 500, I could shoot deer to 75 yds no problem. Sights that attach to a smoothbore vent rib barrel are a cheaper option still.

Another option, and probably the best option, is to get a rifled barrel with a cantilevered scope mount. This will extend the effective range to 150 and beyond depending on the shooter.