my cleaned up 1873 Springfield

[ssgross]

Finally got some cases loaded and some time at the range on my way home from work. Fun evening.
Here is the thread where I sourced, acquired, and cleaned up this treasure.
https://www.milsurps.com/showthread.php?t=73637
Attachment 120642Attachment 120643
New starling brass from Midway. I found 20-1 alloy bullets at https://www.buffaloarms.com
a few months ago, but all they had in stock at the time were 0.458, 395gr round nose from Lyman bullet mold 457124. I used my Lee manual for data, which listed loads for 385gr and 405gr cast bullets with IMR4064, which I have plenty of. I conservatively interpolated between the starting loads with 44gr.

The target above was at 25 yards. My Labradar showed an average of 1590-1617 fps, with a standard deviation of 8fps...so I think I did my job loading! I was expecting about 1275fps based on what the manual said. Also, at 25yds I was impacting 8 inches or so high. in that group I was aiming at the bottom of the target backer to keep it on paper. I had the sight all the way down at the bottom (100yd marking). Making a drop chart from what I saw at 25yds predicted I was zeroed for ~350yds, and would hit >24 inches high at 100yds, which is the extent of my indoor facilities. So, after 3 rounds aiming on the floor at 100 yds just to see a hole on paper, I went back to being content at 25yds for this trip.

BuffaloArms now has 500gr RN from Saeco Mould 1881. I just bought 6 boxes, and it now says out of stock. Now that I have a starting point, I'll dial down my loads for the 395 grainers to get something close to the original ballistics of 1350fps of 405gr. This should help my problem of shooting so high, e.g. at 1275fps a 100 yd zero would have meant only 1inch high at 25 yds. By the way, my bore slugs at a perfect .458, and is in perfect condition!

Information

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[ssgross]

For anyone out there with a LabRadar...I'll save you similar frustration by saying don't forget to change your settings to pistol velocities instead of rifle, otherwise you will get the dreaded "shot cannot be tracked" error. It worked flawlessly after I figured that out.

[ssgross]

Hey, Jim, hoping your luck will continue...can you check the SRS for 168171? Maybe this rifle has a greater chance of a hit given it had rack numbers.

[browningautorifle]

SRS for 168171

Nothing even close to that number in SRS #1...

[ssgross]

Twas worth a try. My 500 grainers came in. Those should match my rear sight as long as I get the velocity right.

[browningautorifle]

I tried those through a Ruger #3, an 1886 Winchester and a Marlin 1895 with no satisfactory effect...they were cast wheel weight but maybe just too long for my twist. I'll never know.

[ssgross]

with no satisfactory effect...they were cast wheel weight but maybe just too long for my twist. I'll never know.

I have no experience with those firearms. From what I'm reading, wheel weights were in the range of ~10-1 antimony. "The Book" (Wolfe https://the4570book.com) specifically says to run away from anything with antimony in it for trapdoors, and to stick with the 20-1 tin, or less tin, for best accuracy. I have high hopes for these, but I'll be happy so long as I don't have to aim at the floor to get on paper like the others

Been thinking about casting for myself over the last year...but the highly prized saeco 1881 mould has not presented itself.

[ssgross]

Took this trapdoor back to the range tonight...with 20 rounds of 0.458, 500gr round nose, 20-1 alloy form buffaloarms.com. Here is tonights data.
45-70-500
Historical target (Wolfe's book): 1315 FPS, minimum acceptable 1270
My results:
500gr, 20-1 soft cast over 39gr. IMR4064
MV average: 1305
Min: 1262, Max 1339
SD 17.8

Took some cross-referencing between all my manuals to make this starting point. I'd say I darn near duplicated the original target!

At 100yds, I put 4 out of 5 of these rounds within 2 inches of each other. I messed up the third shot and it flew 2 in. right of the group. My group impacted 12 inches above my point of aim, and 3 inches right. The M1879 sight was set all the way down. I double checked my front sight post and it is a perfect 0.100 above it's base...exactly what it is supposed to be. This load was very fun to shoot. Next trip I need to make sure my tape measure is in the bag so I can paste my "aiming" target in the exact spot needed to get me all over the bull.

Maybe a third of my cases are showing pierced primers, the rest are fine. Instead of shelling out hundreds on the thicker skinned primers or magnum primers, I may purchase another firing pin and adjust it's max protrusion. They can be had ~$20.

EDIT: Track of the wolf has the LEE M1873, 405gr hollow base mould back in stock. I got me one. I have no pot, no lead...but I have a mould now!