The Powder Goes In Front of the Bullet: The Curious Case of the Greene Underhammer

    Green Underhammer Bolt Action Rifle - Institute of Military Technology Collection

    There’s probably a simple reason why the 900 some-odd Green Underhammer bolt action rifles bought by the U.S. Ordnance Department in the late 1850s/early 1860s weren’t very popular: dumb grunts like me couldn’t figure them out.

    Okay, maybe that’s not entirely fair, but bear with me here. The powder. Goes in front. Of the bullet.

    Greene Underhammer Rifle Cartridge

    It’s okay, I made that face too. In fact, the riddle is pretty simple. Tolerances weren’t good enough to seal the breech in those days, so U.S. Army Lt. Col. J. Durrell Greene designed for a lead seal. In effect, each shot requires two bullets. Here’s how it works:

    Greene Underhammer Bolt Action Rifle, bolt open – Institute of Military Technology collection

    We begin by pulling the bolt to the rear in the normal way, then we place a .53 caliber bullet -just a bullet- into the chamber.


    Greene Underhammer Bolt Action Rifle, plunger driven half-way forward – Institute of Military Technology collection

    We drive the plunger forward, but note how the bolt stays to the rear. At this point, we’re driving a bullet -just a bullet- into the firing position. We’ll then pull the plunger back all the way to the rear again and insert a complete paper cartridge.


    Greene Underhammer Bolt Action Rifle, bolt forward ready to close/lock – Institute of Military Technology collection

    Now we drive the entire bolt assembly forward. The projectile bullet is in the front, the cartridge is inserted with a bullet in its rear. The idea here is that the rear bullet (inside the cartridge) will act as a seal. Note that in this position the bolt lug is visible.


    Greene Underhammer Bolt Action Rifle, bolt locked, hammer cocked – Institute of Military Technology collection

    Now we’ll pull the underhammer down and place a “hat cap” primer onto the nipple. For the uninitiated, underhammers were popular in the 1850s as they provided the shooter with fewer powder burns to the face.

    Now pay attention, this is where it gets complicated and I’m all out of pictures.


    • Fire the rifle, *BANG*
    • Unlock the bolt upward by pushing the button on the tang, then push FORWARD on the plunger, moving the “seal” bullet into the firing position.
    • Pull BACK on the plunger bringing the bolt all the way to the rear.
    • Load a new cartridge (with a bullet in the back).
    • Push the bolt assembly forward and lock it down.
    • Pull the underhammer down and affix a primer.
    • Fire again *BANG*
    • Repeat.

    Simple enough for a dumb grunt, right?

    Reportedly, 3000 Greenes were delivered to Russia though none are known


    Corey R. Wardrop

    Corey R. Wardrop is the Museum Curator for the Institute of Military Technology in Titusville, Florida where he manages one of the finest, if not the finest, firearms collections in the country. Corey is a former OIF infantry Marine and has worked professionally in the firearms industry for over 20 years. In 2014 he obtained an unrelated Bachelor of Science degree from one of the nation’s leading diploma mills. Through his work at IMT he is currently studying CAD design with an emphasis in reverse engineering rare firearms.
    Corey asks forgiveness for his novice-level photographs and insists they are improving dramatically thanks to certified rockstar Corey can be reached at [email protected] and always appreciates suggestions for future articles.
    For the record, Corey felt incredibly strange writing this bio in the third person.