A while back (15 years ago I'd say?), a bunch of PDs in the US were looking at bolt action 'sniper' slug guns with scopes for breaching doors from a distance.
A few builders actually made 12 gauge bolt slug guns with fiberglass stocks, camo paint, and all the typical sniper rifle add-ons to sell to Police Departments.
It wasn't until AFTER all that they realized they couldn't figure out a practical situation where they would breach a door from 100 yards away, where it couldn't be breached by a guy with a shotgun on the entry team.