How do I determine the size of a patch/ball combination?

[Smokey]

When determining the caliber of a patch/ball load, the patch wraps around the ball. The patch fills the space between the bore and the ball on two sides. Therefore, do we multiple the thickness of the patch by 2? 

Example 1:  You want to load a .62 smoothbore.
Wrap a .010 patch around a .590 ball.  Is that now a .610?

Example 2: Same gun, .62 smoothbore.
Wrap a .015 patch around a .600 ball. Isn't that a .630? Won't fit. 

Thanks.

[Darren Haverstick]

The math you are doing is just a starting point. Other factors come into play in reality. The bore of your gun is probably not exactly .62" all the way down the barrel. Likewise, the diameter of your ball will probably vary slightly from ball to ball. The cloth you use for a patch will also compress slightly. Lubed patches also fit differently than dry patches.

Your best best is to pick a ball diameter and then get some patch material of different thicknesses. Try the different patches out and see what fits best. You want a snug fit but not something so tight that you have to hammer the PRB down the barrel.

A tight patch is not all that comes into play for consistent shooting either. Just try several combinations out and see which one gives you the best results on the range.

Just my two cents,

Darren

[Smokey]

Thanks, Darren that's helpful. I know there will be variations in size. The patch may even compress. However, that doesn't really answer the question.
I am indeed trying to figure out how to calculate this stuff as a starting point. Thus, are the examples that I used a correct way to calculate the size of a patch/ball combination? Thank you.

[Ohio Joe]

Many times (more then we may think) an under size ball held in place on top of a wadded powder charge with another wad on top the ball to hold it in place was/is the way to go. I feel you can reach a level of accuracy with either (to include the patch) at short ranges - but I have my doubts that same short range accuracy will ever be consistent at longer ranges with a smooth bore.

(.620 bore)

.010 Patch + .600 Ball = .620

.015 Patch + .590 Ball = .620

you are correct in your thinking that the patch does count for both sides of the ball, so a .010 patch is taking up .020 of the bore, just as a .015 patch takes up .030 of the bore.


 

[Smokey]

Thanks, guys. Much appreciated.

NOW I can start to look at possible combinations. 

[RobD]

TRIAL AND ERROR - no substitute for this because yer asking yer gun what it likes best to be fed, and then how you prefer to load a gun, and why.

the ball size diameter's "rule of thumb" is .010" less than a RIFLES bore diameter.  that's a decent starting point.  smoothbores are a totally different story and can require upwards of .050" less than the tube's ID.  for example, my smoothie's colrain barrel is .617" in bore and i use a .577" ball that's swathed in what some call a tight weave .015" cotton patch cloth.

there is no sane way to measure patch thickness.  accurately measuring cloth thickness to apply to some "standard" is pure fantasy because of cloth thread count and weave, the type of measuring tool and the amount of applied pressure to the cloth.  this is pure trial and error.  one should ALWAYS use as tight a weave of cotton or linen patch material as possible.  for first time testing, take .010, .015, .018, .020 patch cloth to the range for testing.  that's a good starting point.  cigarette rolling paper can be added between the ball and patch to increase the wad thickness, too.

what kind of load?  most of the target shooters want uber tight patched ball loads that require a hammered short starter at the very least.  others (me) prefer a loose patched ball and compromise a bit on consistent accuracy for ease of loading.  to be "period / era" correct, loads were loose because speed of firepower was far more important than accuracy during warfare.

[Smokey]

Thanks, Rob.
The patch and ball must be slightly smaller than the bore. That's helpful advice. 
That'll save me the trouble of pounding on a patched round ball that just! won't! fit!  Because it's the same size as the bore.

[RobD]

Thanks, Rob.
The patch and ball must be slightly smaller than the bore. That's helpful advice. 
That'll save me the trouble of pounding on a patched round ball that just! won't! fit!  Because it's the same size as the bore.

for a rifle, the patched ball should be at least groove diameter - lots depends on the rifling depth.

smoothbores can be tougher because you typically want some compression of the patch as a gas seal - that usually takes more playing around to find a ball/patch combination that's relatively easy loading and yet allows hitting pie plates at 25yds (or maybe 50yds!) routinely.  it really Really helps to have a good patch lube.  i prefer gato feo or just straight up mutton tallow or bear tallow.

[Smokey]

Thanks, Rob and all.
I'll pick up some .010 patches to go with the bag of .59 roundball that I have in my kit. 
Another muzzleloader shooter recently gave me a little container of patch lube.

OR, maybe I'll just shoot the .950 without a patch. Then, get some .570 balls to shoot with patches.

I'll try all of that out for starters and see how it goes.

[RobD]

please remember that the patch material label thickness is a ballpark number at best.  when you find a patch material that works well for a specific gun and you, buy as many yards of it as you can afford!

you would be better off buying patch material and not pre-cut patches - cut off at the muzzle or use a ball board.

personally, i would never load a naked ball - that's an invite to barrel leading, imho.

[prairie dog]

  How far down the rabbit hole do you want to go?   

http://traditionalmuzzleloader.com/index.php/developing-an-accurate-load-for-a-black-powder-muzzleloading-rifle

[prairie dog]

BTW- My 62 smoothbore loves a .600 round ball with an .018 thick ticking patch over 80 grains of Goex 2-f. 
But that doesn't mean any other smoothbore will. 

[Ohio Joe]

How far down the rabbit hole do you want to go?   

http://traditionalmuzzleloader.com/index.php/developing-an-accurate-load-for-a-black-powder-muzzleloading-rifle

Steve, that's a very interesting site you have there. 

[RobD]

that's the beauty of guns - at least 95% is subjective.    

[Maven]

BTW- My 62 smoothbore loves a .600 round ball with an .018 thick ticking patch over 80 grains of Goex 2-f. 
But that doesn't mean any other smoothbore will.   ...prairie dog

My smoothie seems to have the same preferences as prairie dog's, with a few minor differences.  To wit, mine doesn't care whether the RB exactly .600", but will and does tolerate .597" - .603" diameters (Tanner, Lee, and Lyman moulds).  Second, a .014" thick pillow ticking patch (compressed measurement) works just as well as an .018" one, but the latter offers a bit more resistance starting and seating, and possibly a slight velocity increase because of that.  OTOH, a SB shooter of my acquaintance gets enviable accuracy using only 60gr. FFg and practically any combination of .600" RB you can think of:  patched, cartridge, RB with wads fore & aft, etc.