ball diameter for smooth bores

[RichG]

How much smaller than bore should a ball be when shooting a smooth bore? Patched round ball in a .670 Officers Fusil. I'm thinking a .650-.655. Opinions.

[msellers]

That seems to be about the size difference for most. An average rule I have been told was to go .020 smaller than bore. So your thought seems spot on.

[Brokennock]

One of my 20 gauge smoothbore guns likes a patched round ball, the other shoots better with the ball over a lubed wad and held in with a thin card. The gun that likes patched ball shoots best with a .600 ball and a .010 patch. The other gun, the best groups I got with patched ball was with .595 ball and .010 patch, seems like looser is better for this gun, so tried wads instead and found marked improvement.

[Daryl]

.020" to .030" smaller seems to work in most of them.  I use a .595" ball in my 20 bore (.616" bore) and that works very well.
This gun has a standard-type choke. Once the patched ball gets past the choke (short starter), it is exceptionally easy loading.

[hanshi]

That seems to be about the size difference for most. An average rule I have been told was to go .020 smaller than bore. So your thought seems spot on.

What he said.

[WadePatton]

Pursuant to what I've read here before-and not too long ago, you want at least .020" difference for shooting bare naked ball in your smoothie.  If you are so inclined.

So that'd be right handy, to have one ball size that'd work either way.  The unpatched ball will let a lot of gasses by, and require developing a different charge for best shooting and will likely be somewhat heavier than your patched ball load-especially if you want similar velocities. 

I think Hungry Horse is one of our resident experts on such.  I'm just parroting much of what he and others said as this discussion is yet fresh in my mind and folks hardly search for previous discussions anymore. It caught my ear because I love the simplicity of it and is a fourth option for smoothie loading as I see it, those being:  Shot, B&B, Patched, & Nekkid. And having that many options makes smoothie ownership much more interesting to me.

[Daryl]

It does have some endearing features, if your ranges are relatively close, Wade.
It is fun shooting smooth bored flintlocks.

[D. Taylor Sapergia]

I am a proponent of the patched ball.  My philosophy is:  if you expect rifle accuracy or as close to that as is possible, you have to load it like a rifle.

The patch must do two things:  seal the bore to prevent blow-by, and two, carry enough solvent/lubricant to dissolve ALL of the fowling from the previous shot so it can be pushed down the bore to the charge with minimal effort and consistency.

Patches that are .010" for this purpose are useless.  I submit that .020" is minimum, and that's squeezed as hard as possible between the jaws of a Vernier's calipers, just like it gets in a gun bore.  But the math is not as simple as that, in determining the ball size.  Some provision must be allowed for the fabric to impress itself into the lead ball...I suggest .005".

So here's the math:  .670 - (.020 x 2) + .005 = .635".  This, of course, all my own opinion, humbly submitted.

[RichG]

Track has .626 and .648 rbs. maybe I'll try some of each before looking for a mold. I remember using a .715 ball and .022 patch in a brown Bess. shot surprisingly well. The bare ball loading doesn't seem like it would work, but I've never tried it. looks like a little load testing after elk hunting.

[WadePatton]

I agree with Taylor that a snug combo with patch- thick and wet is how to patch a ball for best results and efficiency.  The nekkid ball thing is just a different option-it has tradeoffs for sure.  Try looking up "bare ball" if interested is seeing what all was said before. 

[msellers]

So here's the math:  .670 - (.020 x 2) + .005 = .635".  This, of course, all my own opinion, humbly submitted.

Thanks for sharing your thoughts and further educating us all. It makes perfect sense to me, and the math shows it all clearly as well.

[Flint62Smoothie]

I too see 0.020” smaller as a good general rule.

General Shooting - Snug fit as suggested w/ a thick & wet/damp patch, Hoppes BP lube being my favorite choice. But that does not work well for hunting or in ccccccold weather.

Hunting - I may use the above if only hunting for the day, where I’ll pull the load when done. Or if temps stay above freezing.

Cold Weather (Temps below freezing) Hunting - I switch my lube and maybe the patch too, if not already using this one below.

PATCH -I use ‘homespun’, a thin (0.010”) thick (thin?) 100% patch but of high thread count, which makes it survive the barrel/shot/load much better than the pure thickness would lead you to believe. On tests, in temps < 20-degF I have fired & recovered the same patch w/ a heavy load in my 62-cals, shooting them up to 8-times, giving up only because I couldn’t be bothered anymore. No burn throughs on any!

LUBE - I switch exclusively to Track’s mink oil lube as it is the only lube I’ve never seen not freeze up in cold temps. Not hunting, but at a Winter MZL snowshoe biathlon where I judged the last ststikn when it was ~12-degF out, I witnessed 8 broken ramrods in my 1-2 hour shift. I turned many on to TOW’s mink oil that day!

Other:
Don’t ignore paper cartridges as if well tuned to the barrel, you can load significantly faster and be almost as or just as accurate as a patched load. Once shot my 60” barreled 75-cal Hudson Valley fowler using P-C loads and came in 2nd place to a rifle in a woodswalk Fall 2019, using heavy (> 100) charges of 1Fg powdah to boot!

[RichG]

flint 62 smoothie
do you use a different size ball with the paper ctg's or just wrap paper to adjust diameter?
I too use mink oil, having punched the center out of a crisco patch with a short starter in freezing weather.

[Flint62Smoothie]

do you use a different size ball with the paper ctg's or just wrap paper to adjust diameter?

Same ball, I adjust with the paper, works for me!

[Jerry]

I use a ball patch combination that I can start with my thumb. Cutting the, well greased mink oil, patch
at the muzzle. I have found no better accuracy with a tighter fitting ball and patch. Jerry

[hanshi]

I hunt with prb in the smoothbore exclusively.  My loads aren't as tight as the rifle loads but are fairly snug.  The rear sight has a very wide notch so I can see daylight on both sides of the front blade.  This has worked very well for my smoothbore.