I still use my dads Browning Auto 5 12 gauge.It's a smoothbore and has a ventilated rib,I get3" groups at 100 yardswith Remington slugs.
My dad was a tool maker and he put a flip up peep sight on the back of the gun.
The gun has always shot slugs good.I've tried them all and Remingtons give me the best groups.I've also been shooting the gun for 30+ years, so I'm sure that helps.
I can usemy rifle now in the county I hunt in NY.75% of the time I take my shotgun instead of my 30.06 with scope.
Most of the deer I shoot are 50 yards or closer anyway.
I would be interested in getting a closer look at the H&R

I shoot an old fashion 870 express,. With Federal Slugs it shoots 1.5 inch groups. Drops deer in there tracks.

paid 340 band new with two barrels

At what distance and what federal slugs?

Paul

Hard to beat a Browning A-Bolt if you can find one

True and I won't part with mine