Introduction to 3-inch Ordnance Rifles

I’ve talked around the 3-inch Ordnance Rifles practically from earliest blog posts, but never written about the type as a set.   Time to close that gap and speak directly to this important artillery type from Civil War.

Sort of a segue off previous posts about the big Rodmans, the ordnance rifles were not directly associated with Thomas J. Rodman.  However the big guns and the field guns shared a common “shape.”  To be precise here, the Ordnance Board established the “ordnance shape” and conveyed it through instructions published in 1861.

This shape, or exterior form, dispensed with any external decorations, rings, fillets, and muzzle swells which had appeared on guns for centuries.  The design left only the muzzle face, trunnion face, and rimbase junction as right angles within the gun’s layout.  Such removed places in the mold where air pockets might form, for cast weapons.  The exterior also eliminated all possible points where stress might accumulate during firing.  But think of the ordnance shape less so as a rigid pattern and more so design governance.  Just as with the patterns established in 1841, those adhering to the instructions received the nomenclature – “pattern of 1861” or “Model 1861.”

The Army applied the ordnance shape to all weapons entering production from about mid-1861 onward.  While the first Parrott rifles, did not use the ordnance shape, the barrels later 3-inch Parrotts and larger types used the shape.  Batches of James Rifles, 4.5 inch siege rifles, and new siege howitzers applied the “ordnance shape.”  Oh, and of course the Rodman guns mentioned above.

Gettysburg 4 Feb 12 142
3-inch Ordnance Rifle #512 at Gettysburg

When the Army turned to light field rifles, the same preference applied.  Initial orders to Phoenix Iron Company for wrought iron rifles specified the ordnance shape over that of previous guns produced by the firm.  The instructions also specified that 3-inch rifles use seven groove flat rifling.  The ordnance shape, and rifling specifications, also applied to several other weapons provided by other firms produced around the same time.  In short, not all “ordnance rifles” were wrought iron guns produced by Phoenix Iron Company.  So instead of just one simple “family” of 3-inch Ordnance Rifles, there’s a lot of step-brothers and -sisters.

For organization of my notes here are the variations that I’ve marked:

  • Early production Phoenix wrought iron guns which may or may not have used the original patented method, or perhaps a hybrid of the methods.
  • Middle production batches of Phoenix guns, from registry numbers 236 to 543, which were probably produced using the improved method.
  • Later production batches of Phoenix guns with slight differences to sights and fixtures.
  • Three semi-steel rifles from Swift & Company of Cincinnati, Ohio.
  • Six cast steel guns from Singer, Nimick & Company produced under contract from General John C. Fremont.
  • At least one cast steel gun attributed, but with many reservations, to Henry N. Hooper & Company.
  • While somewhat extending the definition of “shape,” at least two surviving guns from Norman Wiard comply with the specification but with addition of a trunnion band.

All of the guns above bear a family resemblance.  Indeed with the exception of the Wiard gun one must confirm the identity with muzzle stamps. All of these guns have a proper claim to the name “Ordnance Rifle” as well as “Model 1861.”  But each differ in source and history.

So with the extended “family” introduced, I’ll turn to detailed descriptions in future posts.