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Drill sizes for loading blocks.

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Spent several hours in my shop yesterday coming up with the proper hole sizes to be drilled when making loading blocks. The sizes listed are for balls .010" under actual caliber size. Can be used for a lubed .015" or .018" patch. Snug with a .015 patch, tighter with a .018" patch. I have some nice pcs. of CM3 maple., that I'm using for the blocks. I'm waiting on a 33/64" brad point bit for my .50 caliber so I am not listing that as a proper size until I get the bit and test it. They are as follows:
.36 Cal. (.350 ball) - 25/64"
.40 Cal - (.390 ball) - 27/64"
.45 Cal - (.440 ball) - 15/32"
.50 Cal. - (.490 ball) - Pending
.54 Cal - (.530 ball) - 9/16"
I'll post some pics when I get them done.
-Pooch
 
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Spent several hours in my shop yesterday coming up with the proper hole sizes to be drilled when making loading blocks. The sizes listed are for balls .010" under actual caliber size. Can be used for a lubed .015" or .018" patch. Snug with a .015 patch, tighter with a .018" patch. I have some nice pcs. of CM3 that I'm using for the blocks. I'm waiting on a 33/64" brad point bit for my .50 caliber so I am not listing that as a proper size until I get the bit and test it. They are as follows:
.36 Cal. (.350 ball) - 25/64"
.40 Cal - (.390 ball) - 27/64"
.45 Cal - (.440 ball) - 15/32"
.50 Cal. - (.490 ball) - Pending
.54 Cal - (.530 ball) - 9/16"
I'll post some pics when I get them done.
-Pooch

Great Info! Thank you.

Gus
 
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Maybe that chart needs to be updated for ball size and patch thickness.

I use a table like the one in the General Muzzleloading Forum as a starting point. If a loading block makes for a too tight insertion, then the hole needs to be enlarged.

Thank you @pooch156 for investigating the hole diameter for loading blocks.

I use mine for non historically applicable situations as loading blocks are at best very rare.
 
Or we can thank @Eric Krewson for finding the table that was in the General Muzzleloading Forum and @Angie for restoring it to the Useful Tables and information Topic.

Loading Block Drill Bit Chart | The Muzzleloading Forum
Some of those are not quite correct. At least not for patch and ball together. The .36, .45, .50 and .54 are not quite right . . . unless you're using a ball peen hammer to drive them in.
Prove me wrong.
I have found the type of wood (hard/dense vs soft), ball size and compressed patch thickness requires you to sneak up on the ‘correct for you and your gun’ drill size, at least in my experience. For example I have found that a 58 caliber TC Big Bore and a Hoyt 58 caliber radius bottom bore liked different sized holes. The TC Big Bore has moved on, but it’s patch and ball combo was loose in the blocks made for the Hoyt bore. The other way, just about need a hammer. Over .012” difference in patch thickness will do that.
 
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Or we can thank @Eric Krewson for finding the table that was in the General Muzzleloading Forum and @Angie for restoring it to the Useful Tables and information Topic.

Loading Block Drill Bit Chart | The Muzzleloading Forum
It seems like so many questions come up that are easily answered by going to where that table is found. Granted, it was easier to find before,,,,, but, people still didn't use it.
Dram equivalents.
Pure lead ball weight for a given size.
Shot volume in ounces by powder measure in grains. (I worded that horribly, essentially of you use a X- grain powder measure it gives you Y-ounces shot)
Powder by volume in grains for a variety of brass cartridge cases.
The list goes on and on.
 
I have found the type of wood (hard/dense vs soft), ball size and compressed patch thickness requires you to sneak up on the ‘correct for you and your gun’ drill size, at least in my experience. For example I have found that a 58 caliber TC Big Bore and a Hoyt 58 caliber radius bottom bore liked different sized holes. The TC Big Bore has moved on, but it’s patch and ball combo was loose in the blocks made for the Hoyt bore. The other way, just about need a hammer. Over .012” difference in patch thickness will do that.
That is why, in my initial post, I was specific about the type of wood used, ball size and patch thickness.
 
I saved this picture on my computer so I wouldn't have to look it up in the how to section.


loading block drill size.gif
 
I add .015" to the actual size of the ball, you want the patched ball to be loose enough to be started in the muzzle with a short ball starter, but tight enough to not fall out of the block when the block is tapped against a table remember that loaded blocks may be carried for some time after loading, I had a .50 ball and ticking patched load in a block for a year and it functioned okay, I lubed it with some Lubriplate I used to lube my .30 Cal M1 with, because that is what I had handy. I put the patched ball in a 3/4" hardwood block lying on a table with the bottom of the ball flush with the bottom of the block, I found that was where it is eazy to load with the short ball starter, which is a hard wood 1/2" dowell glued in a 1 3/4 inch wooden ball and capped with a .45 ACP brass hull.and cut the excess patch off flush with the top of the lead ball, That is just my way of doing it, it works for me.
 
I like the thickness of a loading block or the setting of the patched ball to allow the base of the ball to protrude slightly from the block. That little bump locates the ball in the muzzle. Of course this means that the spacing of the balls in the block need to allow each ball room to be placed on the muzzle.
 
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