The max penetration Brenneke slugs kick pretty good, so hold on firmly. I'm willing to use a semi-auto for waterfowl or other non-dangerous game. My personal opinion is that a quality, and field tested, pump action shotgun is more reliable. A few less mechanical items to fail on a pump than the semi-autos. Fish & Game issues Rem 870s to all their field biologists, and I believe that selection would be based on simplicity and reliability.
Now I've mentioned the Brenneke max penetration slug only because it's the most powerful hard cast slug in the Brenneke lineup. But truly, their 12 gauge 2 3/4" Heavy Field Short Magnum hard cast slugs at 1 1/4oz would also be plenty sufficient. Brenneke hard cast slugs don't expand, they have a flat wad-cutter style nose, they shoot out of smooth bore shotguns very well, and the 0.730" hole they cut to their full depth of penetration is devastating on large animals at close range. I've talked to the local F&G officer and some police officers who've killed problem or wounded bears and moose with the Brenneke slugs. They all say they flat-out kill everything they've ever shot with them. Because they're a full 12 gauge diameter with a flat nose, they are not the slug to choose for shooting deer or bear at longer ranges, like from maybe 75yds on out. They lose velocity and energy much faster than some of the other smaller diameter sabot-style slugs. The Brenneke 1 3/8oz max penetration slug is just slightly more of any already good in-your-face bear stopping slug. A little more weight, a little more velocity, and more energy & stopping power. However I wouldn't hesitate to use their more commonly available line of Heavy Short Field magnum slugs either.
I killed a bull moose once at extended range, around ~120 yds, with a 12 gauge Brenneke 3" Magnum slug. Was hunting Sandhill cranes - not moose. But I was carrying some Brenneke slugs also, due to bears, and because moose season was also open. I'd never shot one on target past 50yds in my life. This bull moose walks out into the open and I get as close as I can before he sees me and starts to walk back toward cover. Was shooting a Rem 870 with 30" full choke barrel. Nothing but a bead on top of the muzzle of the barrel for sighting. I held about 18" over the back of the bull and touched one off. The bull bolted at the shot so I knew he was hit. He began slowing down as quickly as he'd jumped within about 10-15yds, and then walked until he could go no farther. Made it a total of about 55-60yds and collapsed. The 3/4" entry hole in the chest cavity of the bull was a little too far back and a little low - compared to ideal/perfect into the lungs shot placement. He was still alive when I reached him, but barely, and he couldn't get up. Never even tried. Now this was at 120yds after the slug had lost a lot of velocity and energy. The slug didn't exit, but had I placed the slug in the same location at 25yds or closer, the slug would have passed thru and thru. This was an opportunity of chance, and I took it. The Brenneke's shine in performance at very close range. Not the ideal longer range hunting slug.
