Sharps bore size

[Bob Chabalowski]

Did they measure land to land , or groove to groove,or land to groove when measuring cal. Land to land would seem logical ,Bob

[Bruce Cobb 1723V]

Bore barrel sizes are measured by both groove to groove and land to land. A Sharps being a breech loader the bullet size is usually close to the biggest dia. The bullet for a Sharps breech loader being -.001 or + .001 over groove to groove size. Muzzle loader bullets are -.001 to - .002 under the land to land dia. I think this is the answers your question.

[Bob Chabalowski]

Thanks for the info Bob

[Hickok]

This was confusing even "back in the Day" of the civil war. After reading "Round Balls to Rimfire, Federal Breechloading Carbines..." I will give you my take on the subject of the Sharps 1859-1863 .52 caliber.

The .58 caliber musket used a minie ball that was smaller than land diameter so it could be loaded easily and bumped up to groove diameter when fired. When the Sharps .52 caliber came along things changed. Listed as a .52 caliber, but loading from the breech, it needed a bullet to fit groove diameter, not land diameter, hence though listed as .52 caliber by Sharps, it fired a bullet of about .54 caliber. Sharps listed the caliber by land diameter, the barrels being .520 land diameter with a groove diameter of .540. It thus needed a bullet of .540 to engage the rifling. (Bore and land diameters of barrels made back then were not consistant and varied, but these are the ideal diameters give or take of what the rifle was designed to be).

This caused confusion back then, as some orders for ammunition for the Sharps were requested as, " I need some .54 caliber Sharps ammo for my troops." Federal armory replied, "We don't have any .54 caliber Sharps ammo, as Sharps does not make a .54 caliber Rifle, only a .52 caliber rifle."

Sharps Rifle company finally stepped in and said, "All of our .52 Caliber rifles use and fire .54 caliber bullets."

The Pedersoli Sharps rifles, though listed as .54 caliber, have the same barrel demensions as a true .52 caliber Sharps, groove diameter about .540" and land diameter about .520". So the Pedersoli could be listed as a .52 caliber Sharps as was done back in the Civil war era.

The confusion arises by the listing of a Sharps by groove diameter, or land diameter. Sharps rifle company started this confusion by listing the rifles by land or bore diameter, whereas later most calibers were listed as groove diameter.


I guess we could call the Sharps 1859 the .52/.54 cal Sharps and have all the bases covered!