New to leather, have a question about hole punches

[Waldo Bodfish]

So, this is my first project messin with leather. I am trying to make myself some loading strips, like the ones Colt Faro makes: http://www.coltfaro.com/index1.html

I am having an issue with the bullet hole size for .38's. I first tried the #14 (3/8) punch and it was a hair too big. Then I tried the #12 (5/16) punch, and it is extremely tight. Is there a trick to making a hole just a smidgen bigger?

[Slowhand Bob]

An experiment you might try is cutting a cross hair or X cut slightly larger than the smaller hole punch size.  See if the tiny bit of overlap will allow a bit of a collet affect and if it works give me all due credit but if not, fergit where you heard it!!!  Perhaps someone will chime in with just the perfect punch for the job in a bit.

[Waldo Bodfish]

Well, I got impatient and went to the ole trusty dremel. I had an old worn down grinding head that was the perfect size

[rickk]

I would go with "extremely tight".

It will get bigger with time.

Also, is it finished yet? When you put neatsfoot oil on it, it will soften and the bullets will open the hole up better.

[Waldo Bodfish]

yeah, THEY are already finished. They work okay, but I need to open up the holes just a bit more. Came out looking pretty decent for my first attempt.

[Slowhand Bob]

Rickk is right about the size issue, I think that it will go fairly rapidly from a tight fit through a good fit to being loose, if you are a very frequent shooter.  There are some places where wood has proven superior to leather and I think that even the old cartridge straps have pretty much given way to the wooden loading blocks.

[Sgt. C.J. Sabre]

The answer is easier than you might think. I have done this to make .45 size holes, and it works great.
Take an empty case. Punch the primer out. Using a rattail file, sharpen the inside walls of the case.
You now have a perfectly sized .38 hole punch. After punching holes, use a nail to push the punched leather out of the case. 

[rickk]

Waldo,

for what it's worth. there are also metric hole punches available as well.

You can find them on Ebay for fairly cheap.

They provide the "in between" sizes that some times come in handy if you totally can't get where you want to get with fractional inches. I have quite a few in BP caliber sizes, for punching wads and such.

Keep in mind though that a hole punch is far from a precision calibrated instrument. To start with, they are tapered, so depending on how deep you drive them in the hole size as finished  can vary a bit. Driving it deeper wont change the initial cut size, but it will squish the  hole open a little bit.... the result is noticeable.

Plus, they are somewhat hand made, so the production accuracy is not aircraft industry accurate from one punch to the next.