Range Report 17AUG2025: Buckshot Trapdoor, .45-70-500, & Martini Henry

Following in the footsteps of my friends Keith Katschke and Kyle Schmittle, I made up a batch of buckshot Springfield Trapdoor cartridges and tested them on paper.  I also shot a comparison between the Springfield Trapdoor and Martini Henry, with an interesting result.  We will discuss both tests below.

Buckshot Cartridges

Extant Buckshot cartridge.

Experimental buckshot cartridge. 1879 Ord. Dept. Report p. 331.

My reproductions of Trapdoor buckshot cartridges.

These cartridges were used both for prisoner control and for foraging.  They were tested extensively in period, as attested to in various reports from the U.S. Ordnance Department.  As the picture above shows, they consisted of a regular cartridge case loaded with 40 grains of rifle powder and three greased round balls made of soft lead.

I knew from my experience making gallery loads for the Trapdoor (see HERE) that .454 round balls weighing 141 grains each worked well with the modern brass, so I used these again.  Following the Ordnance Department description I loaded 40 gains of Swiss 2F powder (which has given me exactly the correct velocity with the full cartridge loads), then a .46 card wad (not mentioned in the records, but I didn't know how long I would be storing these before use and didn't want to contaminate the powder with grease), and three balls which I had greased with my standard mix of lambs tallow and beeswax.

I used a dowel to seat the first two balls firmly on the powder, and found that the last ball would barely fit--less than one-third of the ball fit into the case.  I tried seating the balls with my Trapdoor seating die, but found that they got stuck up in the die, and some were damaged removing them from the die, as can be seen on the third from the left in the picture above.  Because of this, I switched to using a hammer and a wooden dowel to press in the last ball, which led to uneven seating depths, as the picture shows.  Next time, I will use the powder compression die to compress the powder by about 1/8th of an inch before loading the balls.  I then crimped the cases as normal to hold the balls in.

I tested the resulting buckshot cartridges at 50 yards from a seated unsupported shooting position.  The target shown below is a reduced-size replica of the original Trapdoor qualification target shown in Captain Stanhope Blunt's Trapdoor musketry manuals.  I used a 6:00 full sight hold for aiming, and the results are pretty remarkable.  The center of the 18-ball group is slightly high; if I had been shooting at 100 yards it would have been spot on, but I was concerned about the group spreading too much at that distance, so next time I will aim about 6-8 inches lower at this range.

It isn't clear in the picture below, but all 18 balls hit the target, with one flyer at the very edge.  A closer examination showed that at least two of the balls went through the holes of other hits.  I conclude that these would make for excellent hunting loads for small game... or escaping prisoners.  For reference, the target is 23.4x16.5 inches.

6 buckshot cartridges, 18 hits.

Comparing the Springfield Trapdoor and Martini Henry Rifles
I shot ten rounds each of my government-loaded Springfield Trapdoor .45-70-500 cartridges and Martini Henry .577-.450 cartridges at 50 yards to compare their accuracy.  To see how I load the Trapdoor cartridges go HERE, and to see how I load the Martini-Henry cartridges, go HERE.

My reproduction Springfield Trapdoor cartridges.

My reproduction Martini-Henry cartridges.

I scored accuracy using the nineteenth-century String Test, which you can learn more about HERE.  I used a full sight picture with a 6:00 hold for both Tables of fire from a seated unsupported shooting position.  For reference, the black circle on the targets is three inches in diameter.

Springfield Trapdoor.

Springfield Trapdoor
10 rounds
String 33.5 inches
String Test: 3.35 in./rd.

Martini Henry.

Martini Henry
10 rounds
String: 22.5 inches
String Test: 2.25 in./rd.

Although the Martini-Henry String Test is more than 1 inch/round better, note that the battlesight setting on that rifle is 100 yards, while that of the Trapdoor is 200 yards.  Given that disparity, the trapdoor naturally shot a little higher than the Martini Henry, which shot close to the sights, just a little high since it was 50 yards), exactly as one would expect.  From this, I conclude that both rifles shot just about the same, and both are excellent analogues for the originals.

The Krag Jørgenson: Working up a Load

 

My 1896 Krag Jørgenson and Mills Belt

I was recently fortunate enough to acquire an 1896 Krag Jørgenson rifle in nearly pristine condition.  I loaded 20 rounds of ammunition, with five rounds each of 4 different powder loads to determine which shot best in my specific rifle.  10 rounds of each would be more precise, and I will test later with that many when I tune these results, but my goal was to get a rough idea of where to start.

As always, my goal is to attempt to match original ammunition as closely as possible, but that is difficult in this case since they used smokeless powder and modern powders are different.  I was told that IMR 4350 is very close to the Dupont powder used in period, so I used that along with a Hornady RN interlock bullet weighing 220 grains since it is a very close match to the originals.

Original Krag .30-40 cartridge design.

My reproduction cartridges.

I will post a detailed discussion of my loading procedure later, but the key here is to note that I made four different loads:
Load I:    34.5 grains
Load II:    36.5 grains
Load III:   38.5 grains
Load IV:  40.5 grains.

Load IV came closest to matching the velocity of the original cartridges at just over 2,050 f.p.s., with the originals coming in at 2,000.

I shot each Table of Fire at 100 yards from a rest, with a 6:00 hold using a full sight picture (this will be important below) on the black disk shown on the target pictures below, with the disks being 3 inches in diameter.  The day was bright and sunny, temperature 85 deg., wind from 3:00 at 10-15 m.p.h. with 27% humidity.

I will show the target pictures below along with the string test results.  I will show the Figure of Merit for tables 3 and 4 only since the FoM is tedious to go through, and these (representing Load III and Load IV respectively) were the best of the day.

To learn more about the Figure of Merit and how to do it, along with a link to a calculator to do all the hard work for you and to a video I made showing the theory behind it, go here:
https://historicalshooting.blogspot.com/2021/01/calculating-figure-of-merit.html

To understand the String Test, go here:
https://historicalshooting.blogspot.com/2020/12/the-string-test-measure-for-historical.html

Table of Fire One: Load I
String Test: 27.5 in./5 rounds = 5.5 in./rd.

Table of Fire 1: Load I.

Table of Fire Two: Load II
String Test: 9.5 in./5 rounds = 1.9 in./rd.

Table of Fire 2: Load II.

Table of Fire Three: Load III
String Test: 8.25 in./5 rounds = 1.65 in./rd.

Table of Fire 3: Load III.  Note that all the spots are from a neighbor trying out birdshot at 100 yards!

Table of Fire Four: Load IV
String Test: 9.25 in./5 rounds = 1.85 in./rd.

Table of Fire 4: Load IV.

So, from these results, it would seem that Load III gave the best results with a String Test of 1.65 in./rd., which is, incidentally, far, far better than I have ever achieved with any other rifle at 100 yards.

Next, however, we will consider the Figures of Merit for Tables 3 and 4, which will show that the mean radial deviation of Load IV was slightly better than that of Load III.  Remember that the FoM only determines the consistency of the group, not how close it came to actually hitting the spot at which you are aiming, whereas the String Test takes both factors into account, just not as precisely.

Here is the target diagram and FoM calculations produced by Rob Enfield's FoM calculator (see the link above) for Load III:

Load III FoM target diagram.

Load III FoM calculations.

Here is the target diagram and FoM calculations produced by Rob Enfield's FoM calculator (see the link above) for Load IV:

Load IV: FoM target diagram.

Load IV FoM calculations.

Thus, from these results we can see that both loads III and IV are excellent, with very similar String Tests and Figures of Merit.  In this case, however, the String Test results actually tell us something important that gives the lie to the seeming superiority of Load III when trying to reproduce the original cartridge:  The Krag sight was designed with a 200-yard battlesight, meaning that at 200  yards you should hit precisely on your point of aim when using a full sight picture.  Since I was shooting at 100 yards, an accurate reproduction bullet should hit slightly high, as these with Load IV did when using a full sight.  This fact, combined with the fact that Load IV came closer to the 2,000 f.p.s. muzzle velocity of the originals, shows that Load IV is a superb reproduction of the original cartridge.