Bore diameter measurement

[bstorric]

So how do you get an accurate bore diameter measurement? I’ve tried with a caliper micrometer but can’t get a real confident measurement. I’d like to be able to put a lead bullet down the barrel and then measure that slug but it’s a sidelock. Can I put a bullet sized larger than the bore down it and use my bullet remover screw to pull it out? Any suggestions?

 

[HC]

For 50 cal, use the shank end of a 1/2” drill bit, then add wraps of scotch tape to obtain friction fit, then measure.

 

[HC]

 

[Idaholewis]

For 50 cal, use the shank end of a 1/2” drill bit, then add wraps of scotch tape to obtain friction fit, then measure.

That is a DARN Neat idea Herschel!! I have never heard of this before? But i can see it would Work AWESOME, Just as well as a Pin Gauge. I learned something Today Thank you for Sharing that

 

[bstorric]

For 50 cal, use the shank end of a 1/2” drill bit, then add wraps of scotch tape to obtain friction fit, then measure.

So 1/2 drill bit with one wrap of scotch tape is perfect. I have to go buy a caliper micrometer now. The last one I used to attempt to measure with was borrowed. But this method works like a charm. Thanks for the help HC

 

[HV-Muzzleloaders]

If it is an inline, you can press a lead bullet into the barrel and then remove it for measurement.

If it is the older style rifle, you would need to drill a small hole in the middle of the bullet and add a bolt so you can pull the bullet back out.

This method of "slugging" the barrel has been used by many.

 

[451whitworth]

Another way would be to put a foot long 7/16" diameter brass rod in the barrel. Then push/pound a .54 RB down the barrel. Invert rifle and shake up and down and the brass rod will hit the smack the ball free. Measure the bore and groove diameter with dial calipers or mic.

 

[Bushfire]

For 50 cal, use the shank end of a 1/2” drill bit, then add wraps of scotch tape to obtain friction fit, then measure.

That's a cracker of an idea, I'm doing that as soon as my new bang stick gets in.

 

[John0313]

Ben - thanks for asking this question, and Herschel for your answer!

 

[Ninering62]

That is a DARN Neat idea Herschel!! I have never heard of this before? But i can see it would Work AWESOME, Just as well as a Pin Gauge. I learned something Today Thank you for Sharing that

Agreed. Me2 learnt somethin new & neat