Here's a link you may want to check out. Essentially, this gunsmith lengthens the shotgun barrel forcing cone to help increase accuracy and reduce recoil and a few other mods. When I was at the Sheriff's office, they had all Patrol Remington 870 shotguns modified by this guy and it was impressive. You could easily put a load of buckshot in the breadbasket on a 25-yard target and could reliably hit B-26 silhouette targets in the chest at 100 yards. IIRC, he also installed a ghost ring aperture sight on the shotguns which greatly assisted accurate aiming. You would still feel the shotgun kick but that recoil was tamed a bit.
Since you have a couple gunsmithing buddies, they might be able to do the work a lot cheaper as a buddy favor.
With these shotguns' accuracy, I could see using slugs out to 100 yards on a pig or deer. I never used one for hunting (they belonged to the Sheriff's Dept.) but I think it would definitely take a large hog DRT.
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