Choice of caliber given a ball size

[Janissary]

I've seen many threads about which size of ball works best for a given bore but I want to ask the reverse question.

Say (not so hypothetically) that I'm going to get a custom barrel, but I want to use cheap ammo, so I plan to use Hornady round ball, of which the largest size is 0.570". I believe the rule of thumb is that the ball should be 0.015" to 0.020" smaller than the bore which implies I should get a 0.59" caliber barrel. However, my suspicion is that just because a 0.57" is the best thing to shoot out of a 0.59", does not mean that a 0.59" is the best bore for a 0.57" ball. If I go up to 0.60" or 0.62", I get to shoot the same projectile with a looser fit and a wider base of powder, and maybe that makes things better in some ways? I'm skeptical that I would lose a significant amount of muzzle velocity or accuracy. Moreover, a bigger bore will always be better for occasions when I want to load birdshot/buckshot. What do you guys think?

 

[necchi]

I'm going to get a custom barrel, but I want to use cheap ammo,

What do you guys think?

I think,,,, that if you can afford a custom barrel,, that you won't need to use cheap ammo..(period)
you speak of an oxy-moron.
Your trying to compare a precision barrel with un-defined projectiles for it, and accuracy?. Mute point.
You are right that a larger bore precision barrel can be compensated too accuracy with the variables of ball size, patch, lube and charge, but only because it's a precise sized barrel. (?)
hhmm,, welcome to the forum.

 

[Some_Mook]

Cheap ammo....relative to the State in which it is purchased? Surprised lead is even allowed to be sold or possessed there...

 

[Grenadier1758]

I've seen many threads about which size of ball works best for a given bore but I want to ask the reverse question.

Say (not so hypothetically) that I'm going to get a custom barrel, but I want to use cheap ammo, so I plan to use Hornady round ball, of which the largest size is 0.570". I believe the rule of thumb is that the ball should be 0.015" to 0.020" smaller than the bore which implies I should get a 0.59" caliber barrel. However, my suspicion is that just because a 0.57" is the best thing to shoot out of a 0.59", does not mean that a 0.59" is the best bore for a 0.57" ball. If I go up to 0.60" or 0.62", I get to shoot the same projectile with a looser fit and a wider base of powder, and maybe that makes things better in some ways? I'm skeptical that I would lose a significant amount of muzzle velocity or accuracy. Moreover, a bigger bore will always be better for occasions when I want to load birdshot/buckshot. What do you guys think?

There is a lot of information that is not being provided here. This topic is started in the smoothbore section, but I get the feeling that you are asking about a rifled barrel, but you do intend to possibly use birdshot or buckshot. You want to buy a custom barrel, presumably for better on target accuracy, but you want to using cheap ammo. Swaged round balls are not as cheap in the long run as cast round balls. There is no mention of the patching material, or in the case of a smooth bored gun, the wads or cards. In any event, the rule of thumb I use for a round ball application is 0.010" smaller than the land-to-land diameter of the rifled barrel. This puts you in the category of a 0.580" barrel or if this is truly a custom rifled barrel, then 0.585". If smoothbored, then the 24 gauge barrel of 0.579" diameter will accommodate the 0.570 ball and the use of suitable wads and cards.

Do a search of the Forum for 58 caliber or 24 gauge smooth bored guns. I think the Kibler Colonial can be built around a 58 caliber smooth bored barrel.

 

[rich pierce]

There is a lot of information that is not being provided here. This topic is started in the smoothbore section, but I get the feeling that you are asking about a rifled barrel, but you do intend to possibly use birdshot or buckshot. You want to buy a custom barrel, presumably for better on target accuracy, but you want to using cheap ammo. Swaged round balls are not as cheap in the long run as cast round balls. There is no mention of the patching material, or in the case of a smooth bored gun, the wads or cards. In any event, the rule of thumb I use for a round ball application is 0.010" smaller than the land-to-land diameter of the rifled barrel. This puts you in the category of a 0.580" barrel or if this is truly a custom rifled barrel, then 0.585". If smoothbored, then the 24 gauge barrel of 0.579" diameter will accommodate the 0.570 ball and the use of suitable wads and cards.

Do a search of the Forum for 58 caliber or 24 gauge smooth bored guns. I think the Kibler Colonial can be built around a 58 caliber smooth bored barrel.

I use a .600 in my .620 and a .662 in my .690 smoothbores, so you are in the right range thinking 0.020” difference between bore and ball size. I’d use .670 in my .69 if I had the mold. I used a patched round ball but that’s another topic where I’ve heard all points of view already.

 

[Old Hawkeye]

Barrels are built to standard industry specifications regarding caliber diameters but they will vary + or - a few thousandths because of machining tolerances, tooling wear & the manufacturer. That is why you fit your ball & patch to the barrel. Why on earth would you want to fit a barrel to a ball & patch? You still are going to have to try various ball/patch combos to see what shoots best in it, regardless how the barrel is made. Really bad idea!!

 

[flconch53]

Many of us cast Round ball for sale. There is alot more out there than hornady. Pick the size of the barrel you want. Isell sell up to .595

 

[Rifleman1776]

Good replies so far. But, the question is really not answerable. In this game each rifle has it's own wants and strange needs. The 'best' of anything can only be determined by trial and error.

 

[oldwood]

Any custom barrel today uses known ball diamiters , and patch thickness. Try not to shoot yourself in the foot right off the bat , by declaring the size ball yYOU want . It's easier to pick the caliber , and the ball , and patch will be evident. Hope this helps.

 

[ronaldrothb49]

This is a first for me, Never heard of anyone picking a ball size to use and then having a custom barrel made to fit the ball. Wouldn't it be cheaper to use a standard caliber barrel that is available and then getting a ball to fit it? Even if you have to cast your own balls it isn't that expensive to get a mold and the pot and ladle to cast them and those are one time expenses that you can use forever.

 

[Rifleman1776]

Never heard of anyone picking a ball size to use and then having a custom barrel made to fit the ball

That's the same guy who finds a button and gets a suit made to match.

 

[Janissary]

Let me clarify - custom gun builder, I think he makes everything himself, and I haven't asked him about the barrels but I'm pretty sure he could bore it to whatever size I'd want. Yes this will be a smoothbore, not rifled, and I mainly intend to shoot round ball without a patch. I didn't set out to get a fancy barrel, just want to buy from him in particular. If he tells me that a particular bore size is cheaper then I will just go with that.

 

[Janissary]

Cheap ammo....relative to the State in which it is purchased? Surprised lead is even allowed to be sold or possessed there...

That raises another question honestly, which is that if I want to go deer hunting, it will have to be non-lead balls, which only come in a few specific sizes. So for a deer gun I think I would start with the ball size and then pick a caliber. But, I have no deer hunting plans.

 

[The Crisco Kid]

.570 ball uses a .580 barrel. 24 gauge.

 

[Brokennock]

As long as something smaller than 20 gauge (.615 to .620 seems to be where most "20 gauge" muzzle loaders barrels come in) I would just go with a .58 cal smoothbore if I wanted to shoot Hornady swaged balls. Otherwise,,,, get a 20 gauge.


As to this question being unique due to the customer wanting his gun to shoot a certain size ball? Well, not so much. I believe in the period, at least mid 1700s to 1800, this is how custom guns were ordered. The customer gave some specs to the gun builder/sticker including a desire that it shoot __ number of balls to the pound and the builder came as close as he could,,,, then providing a ball mold for that gun.

 

[#blackpowderbill]

Have a slug gun made with a conical bullet that you can size.
As far as RB go, the closer to the bore size you get the better it shoots.

 

[necchi]

if I want to go deer hunting,

But, I have no deer hunting plans.

there it is. @Janissary , Please tell us what you want. Nobody can help with your indecisiveness

 

[JeffG]

From my perspective, the math and engineering has already been accomplished. For many years, by shooters much more knowledgeable than me. I see myself as an operator, not an experimenter. Cheap ammunition would be hand cast, by me, but it still has to possess quality to be successful. A shorter voyage to being a proficient, any shooter starts with proven equipment. Once proficient, you can decide if its targets or game you want to shoot.

No need to reinvent the wheel. Just my 2 cents.

 

[Indy Durtdigger]

Am I wrong in thinking since he wants a smoothbore this isn't a big deal at all despite what caliber he goes with? Zinc wheel weights are plentiful. I know he stated he wanted to shoot loose ball but if one were to cast up a mess of zinc balls and use a patch anywho to protect the bore everything would be copesetic. Compliant with the local laws, easily acquired, not limiting in what you have to get at all.

 

[flconch53]

I have suggested modern lead free pewter many times on this forum. Makes a nice ball about the same hardness a lead and is readily available at yard sales etc. I shot some out of my 28 gauge and they shoot good