Steve,
For a scenerio with a brownie charging under 50 yards you want to toss everything including the kitchen sink at it! They're incredably fast with a sloped head that will turn a slug away.They can out run a fast horse for a short distance. If it were my azz on the line like that again I'd want a 'streetsweeper' style semi-auto shotgun with a few slugs first then 00 buckshot. Either that or a full auto 105 howitzer!!!

Once the adrenal glands kick in they can take an incredable amount of lead. Much like a Cape Buffalo or Water Buffalo I'd think. But I've never hunted these yet. Brownies I have.