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 and always appreciates suggestions for future articles.
For the record, Corey felt incredibly strange writing this bio in the third person.


  • Anonymoose

    I understand it, but it seems weird.

    • PK

      Weird indeed!

      It’s no wonder that modern cased ammo was developed so fast, it seems that just about every idea was being tested in this time period.

      The next bullet to be fired, being used as a seal… that’s clever.

      • Matt Taylor

        It is amazing to me the rapid innovation of the modern firearm. I believe you’re right, anyone and everyone was trying something new.

        • PK

          “An idea whose time had come.”

  • Giolli Joker

    It shows that Corey is new.
    Let me fix the title for you:
    “You Won’t Believe Where the Powder Goes! Mind Blown!”

    So… we have a bullet that gets “shot” twice. Cool.
    Seriously, very interesting article, it was definitely new to me.

    • Corey R. Wardrop

      Doctors HATE it!

      Thanks Giolli. 🙂

    • Phillip Cooper

      You forgot “BREAKING: You won’t believe where the powder goes! Mind Blown!”

    • Phil Ward

      Haha “Powder goes WHERE?”

  • m-dasher

    this is the kind of articles TFB needs to be publishing more of….

    • Fffgll

      ^ totally this! 100%

      God! I miss Alex C.

  • A.WChuck

    Not about an AR, not about a Glock. I’ll allow it! 😉

  • Phillip Cooper

    I may not fully understand this, being a formerly dumb grunt (or is that a dumb former grunt??) Seems to me the powder still goes BEHIND the bullet that’s being used as the projectile. What you have here is a sequence where the rear bullet first acts as a gas check, then on the next firing evolution it acts as a projectile.

    Basically it’s a tube magazine.

    • Corey R. Wardrop

      All that’s true … except when you hold the cartridge in your hand and stare at it.

      • GaryOlson

        Until you load the cartridge backwards. I doubt printed instructions were hand written on the cartridge “This end forward”

  • Edeco

    Proper plunger maintenence is essential to reliability and service life in firearms.

    • Nathan Alred

      As in so many things.

    • uisconfruzed

      I marriage as well.

  • Nick

    A paper cartridge breech loader? That’s absolutely ingenuous for that time period. If they could’ve gotten the grunts accustomed to it, it would’ve been far more effective than a traditional muzzleloader.

    Alas, this is an early issue of a designer not considering the foolishness of his potential customer base.

    • B-Sabre

      I could see this as a sharp-shooter’s weapon, where you would expect the troops to have a higher level of training and/or ability.
      I never even knew “underhammer” guns were a thing until now. I could see it being a problem while shooting prone in tall grass.

    • Ken

      Yep, that’s why the Dryse and Chassepot rifles were revolutionary for their time. One major advantage was that they could be easily loaded from prone. There were also far fewer steps to load one of those than the contemporary muzzleloading rifle muskets, which reduced training requirements.

  • Andrew

    So, somewhat like one of MetalStorm’s ancestors? (The superposed pistols being a more direct one). Pretty cool article.

    • Corey R. Wardrop

      Speaking of MetalStorm. I’ve got an article coming up that’s gonna blow your minnnnnd, man. 🙂

      • Pleaseee

        Thus far, your choice of articles make you and Hyrcha, the Armenian guy, the ones to beat. Honorable mention goes to Ronaldo. At least you guys can write a decent article that is not involving Glocks, Ars, or the newest tacticool fad (looking at you Rowland special). James occasionally does decent work as well.

        • Pleaseee

          I also forgot to mention Miles. He does some decent work too, like his article on the PKM.

          • Corey R. Wardrop

            Thanks Pleaseee. I had started an article on one of my favorites – the Blake rifle – but discovered Othias had written an excellent article for TFB in 2014. 🙂

        • Ronaldo Olive

          My honorable Thank you! The more I write on guns, the more I see I know so little!

  • Seth Hill

    Interesting concept.

  • All I can think of is thank God this didn’t catch on.

  • Brett baker

    Considering we had dumped the Hall carbine, if they had adopted this, we would have had a firepower advantage. (Except for the Prussians)

    • Corey R. Wardrop

      The Hall carbine was a clever gun with a lot of advantages, but I believe its Achilles Heel was the lack of any kind of gas seal.

  • gunsandrockets


  • lucusloc

    I really like this as a concept, unfortunately I can see way too many failure points, most of the user induced:

    1. After the last shot fired, the bullet is pushed forwards but the user. Rifle is left empty till next use. On next use new bullet is inserted, and now you have two in the chamber, potentially acting like a barrel obstruction.

    2. In the heat of battle a full cartridge is loaded and pushed forwards, then another is loaded into the proper place. Gun is fired with powder both behind and in front of the main bullet.

    3. You are not sure if the gun is loaded. Open the breach, see a bullet against the bolt face. Is it a bullet that needs to be pushed forwards from a prior shot, or one that has powder and another bullet in front of it? How do you resolve the conundrum?

    4. You have a failure to fire. You do not notice and ram the next round forwards and load the next cartridge. this one goes bang. Kaboom?

    Granted muzzle loaders have similar problems (there are reports of soldiers loading many many shots into a musket after the first one failed to fire. Apparently they just did not noticed their gun never went off.) but since this one works so much faster you don’t have the time to sit and process while you ram powder and ball. That down time may just give your brain a chance to go “ah ha! there was no recoil on that one, I should check that. . . “

    • tsubaka

      3. you will probably see the paper cartridge (or whats left after shooting) rather than the naked bullet, if you see a bullet it will be safe to assume its a bullet that needs to be pushed forwards

      other of your points seems plausible if not correct

      • lucusloc

        Theoretically if the bullet is doing its job sealing the breach the visible paper would not show any signs of having been fired. But yeah, maybe the act of firing will leave a telltale that is easy enough to discern when hastily making ready for a fight. One of the historic guntubers needs to get a hold of one of these and take it to the range to find out.

    • Nashvone

      The thing about the muzzle loaders is that the new round is loaded on top of the old one and progressively further away from the firing chamber. Damp powder may eventually go off but if no powder was ever loaded below the first round, there’s less and less chance of it going off with each consecutive load.

      • Jim_Macklin

        Muskets picked up on the battlefield during the Civil War were sometimes found with as many as a dozen bullets and powder loaded into the barrel.

        If the soldier lost track of how many times his gun didn’t fire or how much of the ramrod was still above the muzzle isn’t known. But cool heads don’t happen when 100,000 men are shooting at each other.

        • Corey R. Wardrop

          But, when you’re supposed to end up with 3″ of ramrod sticking out the top, how do you not notice when you hit bottom and there’s 9″ sticking out the top?
          War is hell.

          • Matt Taylor

            We’ve ALL lied about the difference between 3 and 9 inches before now, haven’t we?

            Honestly though I could see (especially in a civil war style battle) the intensity getting to the point that you don’t notice the difference between 3 inches of ramrod and 9 inches of ramrod. You’re just trying to kill the bastard over there quicker than he’s killing you, not comparing ramrod sizes!

        • Except, this wasn’t dumb grunts getting confused, it was thousands men choosing not to kill likely at the cost of their own lives. If you want to see a fairly ironclad case layed out, read “On Killing” by David Grossman

          • Jim_Macklin

            During the Civil War firearms training was haphazard. The Manual of Arms, right shoulder, left shoulder, sling arms, present arms was taught. But soldiers were often poorly trained at shooting.
            It wasn’t deciding to not kill “the enemy” because if that was teh goal they wouldn’t have been re-re-reloaded.

  • SlowJoeCrow

    Using a bullet as a gas seal is a clever idea but the whole process seems too complicated for operations compared to a simple falling block Sharps.

    • phuzz

      I suppose technically most guns use the bullet as a gas seal at the front, this gun is unusual in that it uses another bullet as the rear gas seal as well.

    • jcitizen

      Since the falling block didn’t exist yet, or was not known, it was better than what they had before.

  • Reazione Catena

    I have a few underhammers and they are fun to shoot, I have a bunch of books on the underhammer rifles and pistols…this is news to me. Awesome piece of history. Thank you

  • wetcorps

    This is pretty cool.

  • uisconfruzed

    That’s a cool design I’ve never seen.

  • BrandonAKsALot

    That is one bizarre design and super interesting. Are we sure it’s not German design with all the unnecessary complexity?

  • SPQR9

    Wait a minute …. I think I got it.

  • underhammer 62

    Now I’m wishing I’d gotten one to go with my other underhammers. BTW underhammers go back to flintlock days. American percussion ones go back to early/mid 1830’s to Hilliard’s and others running to 1870’s.

  • gregge

    It’s a black powder version of a spitwad gun. 🙂
    Get one of those Bic Stic pens where you can pull everything out of the tube.
    Make a ramrod about 2/3 the length of the tube.

    Chew up a piece of paper and insert into the tube then push in with the ramrod all the way.
    Chew up another piece of paper and insert partially into the same end as the first wad went in.
    Hold the tube in one hand then quickly smack the ramrod into the tube.
    The fast air compression between the spitwads *POPS* the forward wad out really fast while the ramrod advances the rear wad to firing position.