I have a few slug guns

Savage 220, 20ga
H&R Ultra Deluxe, 20ga
Remington 1187 both 20ga & 12ga both deer version with rifled/cantilever barrel and monte carlo stock all 4 mentioned topped off with Leupold VX-II 3-9x40, all 20ga I shoot Remington Accutips 3", the 12ga Remington Accutips 2-3/4"

Mossberg 500 20ga, rifled/cantilever barrel Remington Accutips 3", Bushnell Trophy 3-9x40

Also two old Ithaca Deerslayers in 12ga and 20ga smoothbors but I don't use

In order of accuracy:
Savage 220 3/4" groups at 100 yds.my goto slug gun

H&R excellent, just a tad behind the savage

Remington 1187 excellent as well but a tad behind the H&R...in fact I opt for this shotgun over the H&R for the fact the distance I walk and the weight of the H&R

Mossberg 500, very happy with it, for the money excellent value for those on a budget I say buy the combo version....groups are well within a deer's vitals

Remington 1187 12ga. great groups very happy

The group on the solid orange line above center is at 100 yards with my SAVAGE 220, Remington Accutips 3"