What ball sizes to start with?

[Onojutta]

Soon I will be ready to start working up a load for my 20 gauge fowler. I've been shooting flintlock rifles for two decades but this is my very first smoothbore, so looking for some guidance on what ball sizes I should start with for PRB and bare ball loads. I would just order a bunch of different sizes but I just checked TOTW and yikes what has happened to lead prices??? At upwards of $16.69 for just 25 balls, I'm hoping someone can help me narrow it down to just a couple sizes.

Would .600 and .610 get it done, or might I need to go smaller? I generally use .018 pillow ticking for patches and not sure where to begin for bare ball.

 

[Britsmoothy]

What's the bore diameter.
Forget the patch.

 

[hawkenhunter50]

It will depend on your barrel. I have a 20 smoothbore that needs .595 and a .010 patch and I have another that I can use .610 and a .015 patch. If you need a handful of each size I could send you a few, I also can cast .600 also.

 

[rich pierce]

Hard to know what’s going to work until you try different sized balls. I’d start with .610 if it’s a .620.

 

[Grenadier1758]

It's hard to know what to recommend if we don't know what the bore diameter is. While the specified bore diameter is 0.615", many 20 gauge barrel diameters will vary. An acceptable Vernier caliper capable of measuring to 0.001" can be purchased for about $30 from a number of suppliers. Any recommendation we would make is just what has worked for us and may not work for @Onojutta.

 

[Johnny Too-Tall]

Soon I will be ready to start working up a load for my 20 gauge fowler. I've been shooting flintlock rifles for two decades but this is my very first smoothbore, so looking for some guidance on what ball sizes I should start with for PRB and bare ball loads. I would just order a bunch of different sizes but I just checked TOTW and yikes what has happened to lead prices??? At upwards of $16.69 for just 25 balls, I'm hoping someone can help me narrow it down to just a couple sizes.

Would .600 and .610 get it done, or might I need to go smaller? I generally use .018 pillow ticking for patches and not sure where to begin for bare ball.

.595 balls you get twice as many for a few bucks more than if you use .600 Strongly recommend ya buy a mold once u figure out size ya need

 

[Clark Badgett]

It's hard to know what to recommend if we don't know what the bore diameter is. While the specified bore diameter is 0.615", many 20 gauge barrel diameters will vary. An acceptable Vernier caliper capable of measuring to 0.001" can be purchased for about $30 from a number of suppliers. Any recommendation we would make is just what has worked for us and may not work for @Onojutta.

I don’t think I would want to trust $30 Vernier calipers unless they were quality antiques. Cheap dial and digital calibers are fairly decent though.

 

[Grenadier1758]

My father was a toolmaker who left me his Mituyoyo Vernier calipers. I also bought a digital Vernier caliper from Harbor Freight as reading the analog scales on my father's calipers was getting difficult. Readings are usually less than 0.002" apart. These inexpensive calipers are not for toolmakers and machinist, but for the measurements we are making in our muzzleloading hobby, they are certainly acceptable.

 

[Banjoman]

In my .62 caliber smooth rifle, I use .600 round balls with jute tow wadding. Works good.

In my .60 caliber Fusil de Chasse , I normally use shot. I don’t have a proper size mold for it so when I get an itch to shoot round balls, I just use .495’s wadded with jute tow or paper. I can consistently hit a gallon jug out to thirty yards with it.

 

[Onojutta]

It's a Rice. The one Chambers uses for their English fowler kit. I think it's .615 but I don't see it listed on Rice's webstie.

 

[hanshi]

The alloy I had when I cast, for bare ball, dropped balls around .605" or .606". I would have preferred .610" but that's what I had. Later I used the same .600" ball I used with a patch but tested them in bare-ball loads. Careful loading can give good accuracy with bare-ball. I put a card wad over the powder then assembled a thick fiber (a couple of felt wads work) wads with the bare ball on top. I then seated the assembled as one unit. Accuracy was not quite up to prb standards but could still fire reasonable groups at 50 yards. Three shot groups at 50 yards ranged from under 3" to under 5". This would put the bare ball in the deer no farther than 2-1/2" from the aiming point.

 

[Eterry]

It's a Rice. The one Chambers uses for their English fowler kit. I think it's .615 but I don't see it listed on Rice's webstie.

IMHO, or doesn't matter what the company calls it, only a caliper that measures to .001" will tell you. The cheap ones at harbor freight I've seen only measure to .01", totally worthless for anything.
I have a 14 bore that measures .690". I bought some round ball from TOTW, they were way oversize. I found a member who cast .662" and I'm in heaven. When you decide on a round ball, you might post in classifieds, see what the members have. Here's my group from Sunday.
I gotta brag a little.
25 yards, offhand.

 

[Clark Badgett]

My father was a toolmaker who left me his Mituyoyo Vernier calipers. I also bought a digital Vernier caliper from Harbor Freight as reading the analog scales on my father's calipers was getting difficult. Readings are usually less than 0.002" apart. These inexpensive calipers are not for toolmakers and machinist, but for the measurements we are making in our muzzleloading hobby, they are certainly acceptable.

That is my profession. Decent verniers (sliding vernier scale) are easily.0001” accurate. Decent dial calipers are fine for .002” reference measurements. Quality digital calipers can be .001” accurate. Too many use the term for the 3 different types interchangeably, but they are 3 different beasts.

 

[Grenadier1758]

Dad's Mituyoyo calipers were used for quick initial measurements. When it came to precise measurements, it was time for the micrometers.

 

[Onojutta]

Rather than what ball size should I try, let me ask the question another way…

Once I determine the bore size, how much under the diameter should I start with for ball sizes?

What’s a good amount of clearance for the patch, and for bare?

 

[Grenadier1758]

About 1 patch thickness of a thicker patch will do. You will be compressing the the patch to half its uncompressed thickness. This is tight in a smoothbored gun. So with a bore of 0.615 and a patch of 0.015 to 0.018 a ball of 0.595 to 0.600 should work for a modestly tight load. Using a bare ball on top of a wad of tow to form a nest around a ball of 0.605 to 0.610 would work. A smaller ball and more nest/wad would be easier to load and retain good hunting accuracy. Powder charges of 65 grains of 3Fg to 80 grains of 2Fg is plenty for hunting loads.

 

[Clark Badgett]

Rather than what ball size should I try, let me ask the question another way…

Once I determine the bore size, how much under the diameter should I start with for ball sizes?

What’s a good amount of clearance for the patch, and for bare?

To put it quite simply, there is no real need for tight patch compression. There is some historical documentation for patching balls in smoothbores but it is just a singular source at this time, and even then the implied part of that description is a ball patched to a light press for fast and easy loading. One only needs to take up the windage of the ball to help it achieve its limited accuracy and help keep it against the powder. So take your bore diameter and subtract the patch thickness X2. That will give the general size of the ball.
Example: .615” bore - (.015” patch x2) = .585” ball size.
If you have .575” balls just get some .020” patching.

 

[ZUG]

I find that those inexpensive digital calipers you buy for under $25 are just fine for general accuracy work to 0.002" with repeatability. I use them 90% of the time for machining on the lathe or mill. If I want better accuracy, then I use my CALIBRATED STARRETE 4 place micrometer. As a retired aerospace mechanical engineer who has delt with complex measurement issues I feel I am well served with a good digital caliper for under $100. Have a look at <https://www.shars.com/aventor-6-ip67-electronic-caliper-with-anab-accredited-iso17025-certificate> This is my "go to" digital caliper. I also keep two $20 Harbor Freight digital calipers one on the lathe and one on the mill for quick measurements. I have my Starrett 4 place micrometer in the wings as back-up when doing slip or shrink fitting of parts. A big part of using a caliper is knowing how to use them correctly every time you take a measurement. If you can't repeat that measurement two or three times in a row, then you need to learn how to use the tool correctly.

 

[Steve-ALA]

My smooth bore Colerain barrel is .615. I shoot a bare .610 ball with the ball directly on the powder and a thin card or paper over the ball. Shoots very well. If I decide to use a patch, I use a .595 ball with .18 ticking. I prefer the bare ball because it’s historically accurate.

 

[Eterry]

Rather than what ball size should I try, let me ask the question another way…

Once I determine the bore size, how much under the diameter should I start with for ball sizes?

What’s a good amount of clearance for the patch, and for bare?

The thing about smoothbores, in my opinion, is there are many ways to load a ball.
Tight patch, loose patch, ball on powder, ball on tow, ball on a card wad. Ball topped with tow, topped with card. Bare ball or chewed ball, the list goes on.
You'll see shooters use these and many more options. Only time, lead, and powder will show you the best method for your smoothbore.
I went with a ball .028" undersized. I caught a break and it shoots well.

edit: i want to try bare ball, maybe ball between some jute tow, see how she groups.
This is just as much an adventure as reloading.