Round Ball Size For .62 Smoothbore

[Jerry]

What would be the best round ball size for loading a .62 smoothbore with patched round ball. I want to be able to load without a short starter. Thanks, Jerry

[Stoner creek]

I like a .595.

[Maven]

"Best" is a relative term, Jerry as it depends on the diameter of your gun's bore, the thickness of the patch you're using, and possibly how strong your thumb is (LOL).  While .595" will certainly work, my gun prefers .598" with .014" - .018"pillow ticking.  You will also need to experiment with powder charges at the distance you're most likely to shoot. 

[Maven]

It's certainly worth trying, Jerry.

[D. Taylor Sapergia]

My 20 bore Chambers Pennsylvania fowler has a .620" bore.  The gun shoots best with a .609" ball cast from a Lee .600" mold and .020" patch.  Yes, I need a starter but I use one for all my shooting regardless of the gun.  Remember that the patch must be thick enough to carry sufficient lube to soften all the fouling from the previous shot all the way down to the charge...unless you want to clean between shots, which definitely isn't HC. 
I have shot .590" and .595" balls too, but they are not as accurate as the larger ball (.609")   I have tried shooting without patches too, just using wads, and that was a waste of powder and lead.  BTW, my charge is 85 grains FFg GOEX (while it lasts).

[Maven]

I have tried shooting without patches too, just using wads, and that was a waste of powder and lead.

My experience as well Taylor, at least in my NW trade gun (GRF; Barnett copy I think).  However, my .56cal. T/C smoothbore (rifle as has an adjustable rear sight) seems to like unpatched .550" RB's with tow wads fore and aft + 80- or 85gr. FFg...at 25 yd. 

[Daryl]

I shoot balls from a Tanner mould of .595" size, using a 10 ounce denim patch in my mildly standard choked .62 smoothbore.

[Jerry]

I shoot balls from a Tanner mould of .595" size, using a 10 ounce denim patch in my mildly standard choked .62 smoothbore.

Daryl, Do you use a short starter?

[Daryl]

Yes, in every gun I own, no matter if shooting shot or round balls in rifles, pistols and smoothbores alike.
I measured the 10 ounce denim I bought 4 years ago, as .0225". The same squeezed calipers measure the
new 10 ounce denim I bought a year ago, as .021". Different makes of denim I figure, but even this thinner
stuff shoots well and loads just as easily in EVERY one of my guns.  Fired patches from every one of my guns
are re-usable if re-lubed.
The fraying around the outside is due to muzzle-blast.  The higher the pressure as the ball leaves the muzzle,
the more fraying will be evident.
edited: Of course, the weave of the cloth will also have an effect on the fraying degree as well.

[Jerry]

Daryl, PM sent.

[Clark Badgett]

I use .600” balls, bare with a wad on top. Hits what I’m shooting at.

[bob in the woods]

I use a .600 ball in my paper cartridges, and a .610 ball without the cartridge
BTW,
I have noticed that there can be a variance in bore dimensions re the .20 bore barrel manufacturers

[Hungry Horse]

That’s very true all the old barrels from Dixie, that are sold as 20 ga. Are .625 instead of .620. Because those were antique barrels. Probably different now.


  Hungry Horse

[Clark Badgett]

My barrel is .615"

[Brokennock]

My smoothrifle bore measures. 615 and I have best groups for patched roundball with a .595 ball and .010 patch.
I am loading a thin "overshot" card between powder and patched ball.

[stikshooter]

Bob Hoyt did my rebore to 610 to make the Lee 600 mold (actual with pure)595 as cast work , works for me/Ed

[Jerry]

Bob Hoyt did my rebore to 610 to make the Lee 600 mold (actual with pure)595 as cast work , works for me/Ed

Ed, What is your patch thickness? Can you start it with your thumb?

[satwel]

My 20 gauge fowler has a tight bore. With a .590 ball and patch combo I can load with thumb pressure. A .600 ball requires a short starter.

[smylee grouch]

My last smooth bore (20 bore NWTG ) was a little tight to load with its most accurate load so I did the thumb crown smooth job and it worked great. I still used a short starter but it was an easy start even with the tighter combo.

[Standing Bear]

.600

[rich pierce]

Any ball at least 0.020” to 0.040” under bore size can work if you’re using a patched ball. Just find the patch that gives a good seal with that ball.

[Jerry]

Any ball at least 0.020” to 0.040” under bore size can work if you’re using a patched ball. Just find the patch that gives a good seal with that ball.

Thanks Rich, Would a larger ball and thinner patch or smaller ball thicker patch give better accuracy?

[rich pierce]

Any ball at least 0.020” to 0.040” under bore size can work if you’re using a patched ball. Just find the patch that gives a good seal with that ball.

Thanks Rich, Would a larger ball and thinner patch or smaller ball thicker patch give better accuracy?

There’s a bit of witchcraft in smoothbore accuracy with a round ball. I never prefer thin patches. I just figure that thicker fabric equals stronger fabric. I use a .662 ball (28 thousandths undersized ) and 18 thousandths patch in my .690 smoothbore. I guess the fabric compresses. Once started it rams home nicely. Fired patches are perfectly re-usable. In our club I don’t know shooters who use a thin patch under 15 thousandths for anything but cleaning.

[Daryl]

I concur most emphatically with Rich.  Thicker patch, smaller ball.  In a rifle, due to the groove depth, thicker patch and larger ball.