Buckshot is cheap enough. I'd also try improved or modified. If one works for you, no need to go aftermarket, but that's up to you. Pattern Master and Buck Kicker are brands I've heard of. Never tried either one though. I shoot rifled slugs from a smoothbore barrel with rifle sights on my Mossberg 500. This will put slugs in a 3-4" group out to 75 yds. I have more faith in that combo than buckshot. If you are limited to buckshot try to keep shots at 50 yds or less for best results.