I also posted this on Doublegun.com in their double rifle section

After months of preparation and waiting for all the loader, loader components, and reloading components I have finally been able to take my Louis Christophe by Jules Bury 10.75x52R Springer Double Rifle to the range.

I will meander through some of the background on my journey and process.

When I purchased the gun it included the dies and about twenty loaded rounds. The reloaded rounds and brass were 45-70 Brass which was still original length and not trimmed down to 52mm. Based on a notation in the die box I thought it might be H4198 powder. I disassembled a few of them to check their content and determine it was not 4198 powder. Further the powder filled less than 60% of the case and no filler wads were being used, lots and lots of airspace. The cartridges varied by as much as 9 grains in powder weight. I further determined the bullets were straight 0.430 210 grain and not resized to 0.423. Whoever loaded them did not slug the bore and resize the bullets. He may of measure the muzzle which is almost .429 and believed that was the bore size. Bottom-line when purchasing a gun with reloads, it is important to check a few to ensure you know what is in them is correct.

I utilized the only one load I could find online (258grain Bullet/45.0 grains N135) as a benchmark and derived data using Quickload software. I further used data from similar sized cartridges as further reference to see if the data made sense.

I loaded five sets of six cartridges in predicted velocities from 1700 to 1800 using .44 Magnum (.430) 240grain Hornaday XTR (copper jacket hollow point). I had to use the Hornaday Bullet stepped down through several steps to .423 as the 258 grain bullets I custom ordered from Hawks have yet to arrive and I could not wait further. I used Privi 8x56R brass for two sets of loads and Starline 45-70 government brass for three sets.

On the Privi Brass as it comes necked down I initially fire formed them with Unique Powder and Cream of Wheat; then put both them and the Starline brass through the CH4D dies. Both required significant trimming which I need to get better at. Long term I believe I will invest in a power trimmer set-up as the manual CH4D trimmer is a pain.

After firing I could not sense any performance difference between the Privi 8x56R Brass and the 45/70 Brass. There was a 2 grain difference in case volume (74 vs 76 grain). Also the Privi brass has a slightly thinner rim. I still need to clean the fired brass and carefully inspect, but range inspection did not show anything.

All the loads were done with N135 powder. Later I will do some additional loads in IMR3031, Reloader 17, and H4198. They ranged from 44.9grains to 47.9 grains. They filled the case between 77% and 88% and although I probably did not have to I used cut in half Kynock foam filler wads to ensure a 100% fill.

On this initial firing I stayed at 1800 FPS and below. On pressure I stayed between predicted pressures of 14,581 to 12,848 PSI. I say predicted as I have no way of checking the pressure delivered at this time. I also have no sure way to know true max pressure for this cartridge. I have settled on 30,000 PSI based what similar cartridges. I doubt I will risk above predicted 24,000 PSI if I ever even go that far. I was not able to Chronograph the loads tested. I will attempt to chronograph the next firing. I have derived Quickload data to get up to 2000 FPS and to 19,300 PSI. At this point I am not sure I will take it that fast and that high a pressure.

I note this is my first adventure in rifle reloading.

The only loading issue I encountered while reloading is the loose bullet after final press. In other words instead of a tightly crimped bullet the bullet is loose and can be easily pushed and pulled. As my barrel was slugged at 0.423/0.424 the bullets I used were resized to 0.423. I resized a bullets to 0.424 which was still loose, I then resized to 0.427 which resulted in a tighter bullet fit but still not tight and too large a load to fire through my 10.75 bore (in my opinion). I am considering order in a custom crimping die which will give me the final tightness I want. My other option could be a bullet crimper from Stephen Coker (which I am ordering as a case accessory anyway). Because of the loose bullet seating I only loaded and fired one round at a time as I did not want the recoil of the right barrel to unseat a bullet on the cartridge in the left barrel.

I fired from a table with the gun resting on my hand which in turn rested on a sand bag. I fired six rounds alternating barrels in each set. I loaded one barrel, fired, ejected the empty, then loaded the second barrel and repeated. I did not rest the gun more than a minute between shots, with some rounds within 20 seconds. Between sets of rounds there was as much as 15 minutes.

When I first fired I missed the target board completely and could not tell exactly where the rounds were missing except that they hit online on the dirt bream behind the target. I moved the target into 25 yards and determine I was shooting low. I change my sight picture and began to get properly on paper (my first sight picture put the target circle on top of the front sight circle forming a figure eight – I changed to placing the front sight on the center of the target ball). I further flipped up the leaf which elevated the shot group and created a sharper V and that helped. I moved back out to 50 yards again. All said I still feel it is grouping slightly lower than I would want with the sight picture I like to take.

I failed to bring a proper spotting scope and cannot say for sure the order of rounds on the target or which is left and right barrel. Along with chronographing I need keep better record of the fall of each target hit, so I can label each round R1, R2, R3, L1, L2, L3.

I was concerned about how light the rifle when it came to felt recoil. I can report that the loads were comfortable and did not beat me up at all. I was concerned about whether the triggers were be good and the double triggers felt great. Much better than many military rifles I have had to shoot.

The only target photo I am posting is my final target. I only loaded 30 rounds on the initial firing so I ran out of ammo by the time I fixed my sighting issues so I am not sure if I have best performance or not. It is my fastest loading (1800 FPS). A range cease fire interrupted my final shot so I fired the last round into the left of the two targets on the paper as the barrels had cooled. I can say I am very happy with a 2 Ľ by 2 ˝ group. I would like to claim skill, but having seen my other groups (next smallest is 5x8) I am not sure I will do that well again.

Overall Accuracy seems very good. The sight picture bugs me, I doubt I will change the rifle sights, I might increase load speed? No pressure signs on the cartridge cases, and comfortable recoil.

Long term my goal is to develop a light (plinking load) medium hunting and heavy load. Next step is to resolve my loose bullet issue, get the correct 258grain bullets, in meantime load more cartridges in 240grn, some in 220 grain (because I have a bunch of bullets and want to see what I they can do), use a spotting scope to track round by round performance, and chronograph my loads.