Black Powder cartridge question.

Straitshot · August 31, 2011, 11:14 AM

I know some may think this is a dumb question, but when you mic a barrel for bullet size do you mic from the top of the lands or the bottom of the grooves to determine bullet size and how many thousands over if any would be the proper size?

Thanks, Louis

zullo74 · August 31, 2011, 11:37 AM

A simple lead bullet should be sized .001-.002" larger than groove diameter.

Hawg · August 31, 2011, 03:33 PM

Whut Zullo said.

Model-P · August 31, 2011, 11:26 PM

Bottoms of the grooves + .001" or whatever it takes to fill the cylinder throats, whichever is larger.

zullo74 · September 1, 2011, 06:54 AM

Model-P,

For a revolver, you would be correct, but the OP didn't mention a revolver. He said a barrel.

Straitshot · September 1, 2011, 08:31 AM

I am wanting to know concerning lead bullits for a Sharps rifle. Basically though, lead bullits for any rifle. I am trying to determine what size sizer die I need for my 40-70 and 45-70 Shiloh rifle.

Thanks for the replies.

Louis

Jim Watson · September 1, 2011, 09:33 AM

There is a lot of expertise on the Shiloh board at
http://shilohrifle.com/forums/index.php

I don't have a Shiloh but I load .411" bullets for my Browning BPCR .40-65.
It has a Badger barrel which is cataloged at .408" groove diameter. I think the .411" bullets do better because they fit the rather generous Browning throat and swage down into the bore.

I load .379" bullets for my Winchester Single Shot .38-55 largely because that is what the mould drops at. The barrel slugs .3785" with a long throat and I suspect it would do better with a larger bullet, but am now shooting the .40-65 most of the time and don't have the incentive to work hard on the .38.

Model-P · September 1, 2011, 08:55 PM

Quote:

Model-P,

For a revolver, you would be correct, but the OP didn't mention a revolver. He said a barrel.

And that's exactly why I worded it the way I did....

Quote:

Bottoms of the grooves + .001" or whatever it takes to fill the cylinder throats, whichever is larger.

As a Sharps has no cylinder throats, .001" would be the larger of the two

. (See? The formula works fine for revolvers and rifles

).

August 31, 2011, 11:14 AM	#1
Straitshot Senior Member Join Date: July 27, 2011 Location: West Texas Posts: 199	Black Powder cartridge question. I know some may think this is a dumb question, but when you mic a barrel for bullet size do you mic from the top of the lands or the bottom of the grooves to determine bullet size and how many thousands over if any would be the proper size? Thanks, Louis

September 1, 2011, 08:31 AM	#6
Straitshot Senior Member Join Date: July 27, 2011 Location: West Texas Posts: 199	I am wanting to know concerning lead bullits for a Sharps rifle. Basically though, lead bullits for any rifle. I am trying to determine what size sizer die I need for my 40-70 and 45-70 Shiloh rifle. Thanks for the replies. Louis Last edited by Straitshot; September 1, 2011 at 08:37 AM.

August 31, 2011, 11:37 AM	#2
zullo74 Junior member Join Date: August 8, 2009 Posts: 374	A simple lead bullet should be sized .001-.002" larger than groove diameter.

August 31, 2011, 03:33 PM	#3
Hawg Senior Member Join Date: September 8, 2007 Location: Mississippi Posts: 16,188	Whut Zullo said.

August 31, 2011, 11:26 PM	#4
Model-P Senior Member Join Date: February 24, 2009 Posts: 727	Bottoms of the grooves + .001" or whatever it takes to fill the cylinder throats, whichever is larger.

September 1, 2011, 06:54 AM	#5
zullo74 Junior member Join Date: August 8, 2009 Posts: 374	Model-P, For a revolver, you would be correct, but the OP didn't mention a revolver. He said a barrel.

September 1, 2011, 09:33 AM	#7
Jim Watson Senior Member Join Date: October 25, 2001 Location: Alabama Posts: 18,535	There is a lot of expertise on the Shiloh board at http://shilohrifle.com/forums/index.php I don't have a Shiloh but I load .411" bullets for my Browning BPCR .40-65. It has a Badger barrel which is cataloged at .408" groove diameter. I think the .411" bullets do better because they fit the rather generous Browning throat and swage down into the bore. I load .379" bullets for my Winchester Single Shot .38-55 largely because that is what the mould drops at. The barrel slugs .3785" with a long throat and I suspect it would do better with a larger bullet, but am now shooting the .40-65 most of the time and don't have the incentive to work hard on the .38.