Tuesday, April 20, 2021

Loading Ammunition for the Mark IV Martini-Henry Rifle

INTRODUCTION
In 1873, the British government adopted the “Small Arm, Ball, Rifle, Breech loading, Martini Henry Mark III.”  This cartridge was designed from the .577-Snider cartridge, but “necked down” to hold the .45-caliber Martini Henry bullet, hence the “.577/.450” designation.  Like the Snider cartridges, it consisted of a .577 base consisting of metal cups supporting a rolled-foil brass case.  The overall length of the case was 3.15 inches.  The Mark III cartridge was to last for at least 20 years.

The Mark III had a paper-patched bullet 1.27 inches in length and weighing 480 grains; the bullet was tapered and smooth sided and made with a 20:1 lead and tin bullet to harden the bullets against the intense acceleration of the heavy powder charge.
Foil-wrapped Cartridges.
The powder charge was 85 grains of R.F.G.² powder.  Its density is somewhat greater than that used for other rifled small arms, which is known as R.F.G. (Rifle Fine Grain)” (Wolseley, Garnet J. The Soldier’s Pocket Book for Field Service. London: MacMillan and Co., 1886, p. 26 and p. 107).  According to Brett Gibbons of PaperCartridges.com, R.F.G. powder was made from Dogwood charcoal and had a mesh of 16-20 squares/inch at first, then was changed to 12-20 mesh for the Martini Henry whereafter it was termed R.F.G.² (see: https://youtu.be/-yjepTZ-lH4).  For comparison, according to the company web site, Swiss brand 2F powder is 14-19 mesh and so is a reasonable match, a fact confirmed by the muzzle velocities achieved during Captain Gibbons’ testing of his P-53 “Pritchett” cartridges using Swiss powder (see the above video at 22:39).  The cartridge was loaded with a carded-wool filler and a beeswax grease cookie.
Cut-away view of the Mk III Cartridge.
During the Sudan Campaign of the Anglo-Sudan War (1881-1899) the Mark III foil-wrapped cartridges were found to be problematic.  The foil-wrapped cartridges were expanding in a way that made extraction extremely difficult, necessitating the use of the cleaning rod to drive them out of the chamber.  The second version of drawn-brass cartridges was extremely successful and these were adopted formally in 1885 and shipped to Egypt immediately.  Lacking the tools and expertise necessary to make the foil cartridges, it is the drawn-brass ones I seek to replicate here.
A Mk II drawn-brass cartridge.
PREPARING THE CASES
Contrary to popular opinion, black powder is not particularly corrosive.  It is, however, extremely hygroscopic, and the water that it absorbs will combine with the salts in the remnants of the powder to corrode brass quickly if not cleaned thoroughly.  These salts are strongly alkaline, so a mild acid will neutralize them.  For this purpose I put the fired cases into a solution of equal parts water and common white vinegar for ten minutes.
 
The next step after neutralizing the powder is to remove the spent primers.  I had a special frame made for various loading jobs.  A punch is inserted into the case so that the point sits into the opening of the primer; it can take a bit of fumbling to ensure that the point of the punch is exactly centered, but it is important to get it exactly right or the point of the punch may be damaged.  A hammer is then used to tap the spent primer out.  Only a few light taps are necessary—if it takes more, then the point of the punch is probably not centered correctly.

Once the primers are removed the cases are ready to be cleaned.  I am fortunate in that I have access to an industrial tumbler used for cleaning and deburring delicate parts.  Simple tumblers can be purchased at any reloading company, but the industrial unit I use can fully clean the cases in approximately fifteen minutes rather than the three-plus hours regular units require.

The cases come out of the tumbler bright and shiny.  I rinse them with water to remove the cleaning solution from the tumbler, then blow them dry with compressed air, or they can be set aside to dry on their own.  Once dry, the cases are ready to load.

PRIMING
The cartridge cases (purchased from X-Ring Services and made from 24-gauge Magtech brass shotgun shells) take large pistol primers.  The procedure is extremely simple:  A primer is placed on a metal plate.  The case is then set on top of the primer, and a dowel rod is placed inside the case, taking care to center the primer exactly in the primer cup of the case before starting.  Next, a hammer is used on the end of the dowel rod to drive the case down onto the primer until the base of the case is flush with the metal surface.  Ensure that the primer is fully and completely seated in place by running your finger over the primer to be certain it does not sit proud of the case at all; if it does, another tap is called for.

NB:  The process of preparing the cases is identical to that I describe in my post about loading ammunition for the Snider-Enfield.  Refer to this post for detailed pictures of that process.

BULLETS
The bullets used for this project were purchased from Blue Falcon Bullets (found on Gunbroker.com).  They are paper-patched hardened lead, weigh 540 grains, and are 0.468 inches in diameter.  The quality of these bullets is excellent and I recommend them highly.
Martini-Henry bullets from Blue Falcon Bullets.
LOADING
The picture below shows all of the components of my cartridges, including a primed case, the paper-patched bullet, a cotton ball, three card wads made by punching out a waxed cardboard milk carton with a 12 mm punch, a powder measure holding 85 grains of Swiss 2 F black powder, and a tray holding a ¼ inch-thick layer of grease made from equal parts beeswax and olive oil.
All of the loading components.
The die set here is a custom set produced by X-Ring Services.  It contains a die body, a decapper (which was not used here in order to keep the black powder residue out of the die set), a sizing die, a flaring die, a bullet-setting die, and a case holder.
Martini-Henry reloading dies from X-Ring Services.
The first step is to “neck” the case using the sizing die.  This returns the neck of the case to the correct size (they can expand too much when fired).  First, a small amount of case lube is applied to the neck of the case, then it is driven up into the die.  Care must be taken to only size the upper part of the neck where the bullet will actually sit.
Neck Sizing.
The next step is to add a measured charge of powder to the case:
Adding the measured powder charge.
Next, one-quarter of a cotton ball is inserted into the case over the powder to fill up the space the powder does not fill:
Adding the cotton filler.
A card wad is placed on top of the cotton wad:
A card wad on top of the cotton filler.
Then a grease cookie is added on top of the card wad by inserting the mouth of the case into the grease:
Punching the grease cookie.
Two card wads were then added on top of the grease cookie.  The purpose of these two wads is to separate the grease cookie from the bullet; the first was sticks to the grease cookie, and the second wad separates the bullet from the first wad.  That way, the grease cookie does not adhere to the bullet, which would impair the motion of the bullet.
Two more cards on top of the grease cookie.
Once the wads have been added, the case is complete and ready to receive the bullet.  I start by filling all of the cases, then, when they are ready, I take them to the loading press for completion.  First, the mouths of the cases are flared.  It is important to flare the cases the absolute minimum amount necessary for the bullet to be seated.  I started by setting the flaring die so that it barely touched the case mouth, then I lowered it slightly, tried a case, tested by trying to insert a bullet, rotated it in slightly more deeply, tried the case again, etc., until the die just barely flared the case enough to start the bullet, but not enough that it would be possible to press the bullet in by hand.
Flaring the case mouth.
After all of the case necks were flared, the bullet-seating die is inserted into the die body, and the bullet is gently seated in the mouth of a case, the whole then inserted into the loading press.  As with the mouth flaring die, the die was set too high at first, and only gradually lowered as the cartridge is checked for depth of seating.  Once the bullet was set at the correct depth (such that the overall length was 3.15 inches), the bullet-seating die set was screwed tightly into place and each of the other bullets seated in their cases.  The pictures below show that cartridge just set in the press, and then the cartridge driven fully in.
The bullet and case set in the press.
The cartridge driven into the die to set the bullet.
Measuring each cartridge to ensure the proper seating depth of 3.15 inches.
A finished batch of cartridges.
NB:  I inadvertently flared the case mouths of my first batch of cases too much.  It is important to flare the mouths only enough to just start seating the bullet, not so much that the bullet can actually be hand-pressed into the case.  To correct this, I ran the finished cartridges back up into the neck-sizing die part way--just enough that the mouth of the case was crimped slightly to the bullet, and no deeper.  This corrected the problem.  My thanks to Cliff Galbraith for explaining this technique.

PACKAGING THE CARTRIDGES
As always, simply loading the cartridges is not enough from a historical shooting perspective--they have to be placed into period-correct packaging as well.  Anyone who has seen the post on this page showing how the Snider cartridges were packed (here) already knows how these cartridges were packed, because the process is identical, with only the label changing.  A frame is set up, and a pre-cut, pre-printed label is laid within it, then the cartridges are laid in it in a nose-to-toes orientation in two layers of five rounds each with a piece of paper wound between each adjacent round.  Finally, the entire package is wrapped like a Christmas present and tied with a blue and white cord (with which the British seemed highly enamored, for some reason).  Note that this label is a commercial (rather than military) one, which seemed appropriate given that my rifle, a Mark IV, was issued to the volunteer regiments in Britain.
A finished cartridge package.
An extant cartridge package (with a military label).
CREDITS
I would like to extend my sincere thanks to Martyn Robinson of X-Ring Services (xringservices@yahoo.com) for the cartridge cases and dies—for all your Martini and Snider needs, you cannot do better than Martyn.  I would also like to extend sincere thanks to Grant Rombough for excellent information and for providing the label design used in making the package wrapper.  This loading process was taken from the superb videos by Rob Enfield of the British Muzzleloaders YouTube channel.  You can see his videos here:

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