Ball Size For .54 Smoothie

[JJohnson2023]

I have a percussion traditions .54 blunderbuss with a 16 inch barrel. It is smoothbore for those who are unfamiliar. I shoot .530 unpatched round balls out of it. It's my understanding that smoothbore roundballs are generally not patched. Do you think I could get better accuracy by patching the .530's or moving up to an unpatched .535. Thoughts?
I'm aware that this smoothie with a 16 inch barrel isn't going to be shooting 100 yards but I have my shots about 4.5 inches off the bullseye at 28 yards. My whole grouping was 9x5 inches.
Edit: I'm using an 80 gr charge of 2f Goex. I'm open to changing powder charge as well.

 

[Des52]

I patch the balls for all my smoothbores, I get the best accuracy and don't have to put a over shot card or anything over the powder. Shooting with a well lubed patch also lets me shoot without swabbing the barrel till I am done shooting.

 

[chsnlions]

Use a patch and shoot it just like you would a rifled barrel. I would start with 60 grains, .530 ball and .10 or .15 patch. Play with it and move up with grains, it should shoot better than what you have now, with a shorter barrel I would bet you are burning powder after it exits the barrel using 80 grains. But use a patch, your barrel will not be as dirty either with the powder blowing by the ball like it likely is now.

 

[Cruzatte]

Do you think I could get better accuracy by patching the .530's or moving up to an unpatched .535. Thoughts?

I think you'll find it most instructive if you try the above as an experiment. Then post photos on the forum to show us your results. Should be fun.