Well....... had a whole page of info typed & hit the wrong button & lost it.
Were it me, I would go with the Rifle hands down. More accurate by far at anything past 50 yards. BUT,
I have seen smoothies shoot some remarkable groups at 50 yards. I had not built a smoothie for years simply because of the inaccuracy talk. After building building for years, decided I had to build at least 1 & did for myself. Don't remember the Ser# but I know it is past 100 as it was 2016 I think & I was going to take it
to Friendship to shoot &
Life got in the way & I never made it. (I think I actually built it in 2014 & never got a chance to shoot work loads for 2 yrs)
Anyway, you can see this is the 30 yard target is under 1" group of Three. 50 yard was about 1.5" or 1.75" but I know it was under 2". I have killed 6 deer with this smooth rifle with 51 yards being the longest shot. It did what I needed & I have never shot it at any further distance.
As with any of my target shooting for groups, I always shoot off sand bags & always shoot groups of 3. Document EVERYTHING on the target & change load Slightly & then shoot New target. Then I compare targets. This one just was on the bullseye because it ended up being my hunting load. Normally I keep sights OFF the bullseye while working loads.
Now, for me, This is a good STARTING load if I were working loads for a Rifled Barrel. Because I know a rifled barrel will do this at 50 yards. So I would go out to 50 yards & start working loads, grease, liquid lube, balls & etc to work up a better load. It may take me Weeks & hundreds of shots. Hundreds of targets, just to find that One Best Load. Most guys always blame the rifle or the barrel. I don't believe it. Most barrels made today will Outshoot the marksman by far, they just have not found the barrels optimum performance.
Most never achieve that best load because they don't want to do the time, money, documentation & patience to come up with that load. Everyone is in a hurry, so it seems. But Documentation is Most Critical as if you don't document it, you repeat things over & over & waste time & money. And I Always work loads off a bench with sand bags & eliminate shooters error.
Sorry so long winded, but I say go with the Rifle. Get the smoothie later for rabbits. To me, the only thing to shoot Upland game with & waterfowl is a Double Barrel. I have killed hundreds of quail with a double 24 gauge. (Birddog6) Even killed a pheasant with a Snickers bar one time & have witnesses, but that is a whole dif story for a dif time.
Go with a .54 or .58 rifle for deer & elk. Go with a .40 for squirrel & coyote. Go with a 54, 58, or .62 smoothie for birds. And that is just one dumb ol mans opinion.