Proper drill bit size

[Bobcat]

Getting ready to make some ball blocks for my .54 [.530 balls] and it dawned on me that I don’t have the correct size bit or auger. What have you guys found works best?

[JPK]

35/64 ths works well for me.

[MuskratMike]

I use a 9/16 bit to start. Depending on ball size and patch thickness you may or may not need to "hog" out the hole a little. I shoot a .530 round ball with a .015-.018 thick patch. After greasing with T.O.T.W. mink oil/grease it swells to .020, the picture is of my rattlesnake tail antler ball block. The hole was made very slightly larger to accommodate the ball and greased patch for hunting. When making your hole it's kind of like adding salt to the soup. You can always add more but it's very difficult to remove. So start with 9/16 grease up a patch, let it sit for a day to absorb the oil and swell. Wallow out what you need to make yourself happy. Oh by the way a 35/64 will work just as good.

[recurve]

.32=21/64
.36=3/8
.40=27/64
.45=29/84
.50=1/2
.54=35/64
.58=19/32
.62=5/8
.69=11/16
.75=3/4

[Bobcat]

Thanks guys, much appreciated.
Keep your powder dry!

[Eric Krewson]

Recurve beat me to it. I have several .54s so I ordered the correct drill bit off eBay, I couldn't find one locally. Now I have plenty of ball blocks for my .54, so do my friends and I sent several out for free to guys here who wanted to buy one.

[Daryl]

One thing to think about, is to finish the block with tung oil, or something like true oil, so it does not absorb the lube
from your patch.
As you can see, the top hole was not large enough and broke out on the .69's block. I made this up before I switched to
paper ctgs. for subsequent loads.
BStrickling (board member) found paper ctgs. worked well from his .72, on down through his .58 & also to his .54 calibre.
These can be wonderful for hunting in freezing climates. Indeed, they worked for me even in -56F temps.
ps- I would not even consider hunting in -30 any more, let alone -56. I wore a younger man's clothes, then.Those temps
are hard on mainsprings as well. I was just lucky with mine.
The blocks are for my .36 and the .69.

[davec2]

I drill the hole undersize and then use a taper pin reamer to adjust to the right fit for the ball and whatever patch thickness I am using.......here is an excerpt from an old post .....

It requires a bit of investment, but a few taper pin reamers of various sizes come in handy for a variety of hole size adjustment issues.  The ebony loading blocks below are for .32 and .50 cal round balls.  I drill the holes undersize and then use a taper pin reamer, from both sides, to precisely adjust the hole size to grip the ball (any size ball and any patch thickness) the way I want. 



I also use these reamers to open up the bores of cast ram rod pipes, etc.  The reamer in the photos below is a Number 8.  I use #s 7,8, & 9 the most and those three have been worth more than what they cost over the years in making hole adjustments quick, easy and precise.




Original post here:

   https://americanlongrifles.org/forum/index.php?topic=7673.msg72653#msg72653

[Daryl]

Madagascar Rosewood would make a good loading block that does not need finishing,
just final sanding to smooth it. I made the reel seat for my Sage 15' fly rod blank out
of Madagascar Rosewood, no finish and it's as beautiful now as when first made. The
wood contains it's own oil & will not 'take on' moisture of any sort.
Those ebony  blocks, tool handles & tools  are REALLY special, Dave. WOW!

[B.Habermehl]

When utilizing more plebeian woods like maple, walnut oak etc. I use Irwin speed bore bits. By carefully filing each side of the bits and checking them with calipers, you can customize a bit to drill any diameter hole you desire. I use these custom bits to make my ball blocks. I use a dremel tool to mark the size on each bit when I’m done my file and test work. You must drill your block from both sides to get a nice hole. Switch sides as soon as the pilot spur starts to show on the far side. BJH

[Daryl]

As was mentioned, sort of, earlier, drill undersize and open up the holes as needed, with a file. Check after finishing as that
might shrink the holes, slightly.