OK your wanting your gun to do two different operations . Smarter people than us figured out how to do this. Slugs shoot the best from an open choke. That's a fact . There are exceptions to every rule but most guns this is true. So start with an open choke and sight your slugs in. Then purchase reduced recoil buck shot made for LE . Speer and Remington are both available . Lower velocity yes but the buckshot does not deform leaving the bbl fly straighter without the flat spots we have all seen on Mag buckshot and the round projectile actually penetrates better. So that is the teck answer to your question form someone that lives in a shotgun only state and has mega hours researching this same problem. J.Michael

If it were me, I’d sight it in for slugs at a closer range, say 50 yards, but we hunt pretty thick cover. Then, I’d see how it patterns with a few different buckshot varieties. I tested out a TAC-14 Remington with an ‘arm brace’ a few months back. It shot about 12” patterns with the Winchester ‘military’ OOBuck. When I switched over to Federal Flight Control, it shrunk down to a few inch diameter pattern. This was at 15 yards, which is about the longest shot I’ll have in my home. I hope you get lucky as far as having buck and ball hitting the same spot.

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I'd sight it in for slugs and compensate using Kentucky windage with the buckshot. I recently got the itch to shoot slugs after watching Hickock 45 shoot them like a rifle out of a Mossberg 590, Maverick 88 and a few others. So I bought a slug barrel from Ebay for my Mossberg 500 and the Magpul buttstock and a rubber forearm.

I will sight it in with the basic foster slugs from Winchester and Remington. I have gathered up Lee 7/8ths oz. and 1 oz. molds along with hulls and a variety of wads to experiment with loads that travel slower than the brutal factory slugs. Hoping to match the accuracy. It is a great experiment to find the right load for those drive key slugs from LEE.

As far as chokes go it a crap shoot. I once had an 870 with a 30 inch full choke that would place a foster slug in a pie plate at 100 yards just by putting the bead on the center of the plate and firing. I traded up a slug barrel with sights thinking it would do better and be easier to hunt with but It was a splatter match event at 50 yards compared to the full choke barrel. Seems I've seen tests where Imp Cyl is the best.

Bob