Well, after four months of no serious shooting, I figured it was time to get to the range and try out a new powder. I've been very interested in IMR SR4759 for the reason that it seems to give a pressure curve very close to black powder. Here's a report on the results of my first two loads, which turned out to be a bit conservative.
Rifle: Winchester Model 1892, made in 1913
Caliber: 38 W.C.F., also known as the 38-40
Original Black powder ballistics from 1896 Winchester catalogue: 180 grain pure lead bullet @ 1,268 fps
Load #1: 15 grains of IMR SR4759 under a 180 grain RCBS FN PB bullet sized to .401
Load #2: 17 grains of IMR SR4759 under a 180 grain RCBS FN PB bullet sized to .401
I'm proud to say that I cast these bullets myself (just started casting last fall)!
Chrono results of Load #1: 974 fps with an E.S. of 27 fps and an S.D. of 12 fps (5-shot reading)
Chrono results of Load #2: 1,094 fps with an E.S. of 105 fps and an S.D. of 35 fps (10-shot reading)
Here's a photo of my old 96-year old 38-40 ....
First off, I tapped the rear sight over a tad, since previous trips to the range showed that it was hitting a bit to the left. To see if I'd adjusted properly, I set up a target at 50 yards and I fired off two rounds that had not been neck sized at all. The bullets were loose in the neck and held in by the crimp. I didn't want to use these in my official test, so I used them as sighters. The two bullets were very close to dead center laterally so I set up a target at 100 yards. Interestingly, the two bullets that were loose in the necks gave me exactly 100 fps more velocity than the same 15 grain load did when I sized the neck halfway down to the shoulder.
Load #1 Results at 100 yards:
First off, I was amazed at how slow the velocity was. Ken Waters lists 1,153 fps for the same load. Mine putted along at a sedate 974 fps. The rear notch is a small notch within a larger notch, making the top shoulders of the sighting notch not well defined. As a result, my vertical hold was a bit dicey. After 8 rounds fired into the 100 yard target, I had a horizontal spread of only 1 & 1/2", but a vertical spread of a whopping 4 & 1/4". I'm sure it was the problem of the poorly defined shoulders in the rear sight notch. I will have to do some work on that notch. Anyway, here is a photo of the target .....
Load #2 Results at 100 yards, 5 minutes cooling after first 2 shots:
I tried a lot harder to obtain some sort of consistency with my vertical hold on the rear sight notch. After two shots, I headed down range to take a look. It was encouraging, so I went back and fired off the remaining three rounds for this set. Again, I was surprised at the low velocity I got compared to Ken Waters for the same load. He got 1,339 fps and I only got a measly 1,094 fps. The necks were still sooty, so I'm definitely not getting a very high pressure with this load. I got a decent 5-shot group of 2 & 3/8" (100 yards with open iron sights). Still possibly a bit of vertical spread, but I was pleased. Here's a photo of the target ....
Load #2 Results at 100 yards, 5 fairly quick shots, no cooling:
Finally, I decided to crank out 5 shots in a row with no cooling, but still with reasonably careful aiming. This group was not too bad, 5 shots forming a 2 & 7/8" group at 100 yards, but it was spread a bit more horizontally. I wonder if it was from a warming barrel. Here's a photo of that target .....
Concluding thoughts:
Ken Waters lists the max load for Group two rifles as 19 grains of IMR SR4759. I don't know if his batch of 4759 was different from mine, but I do know that his batch would have been a sight older than mine, just bought this past month. I really want to develop a hunting load of around 1,500 fps. Next loads will be 18 and 19 grains of SR 4759. If I can't get 1,500 fps with the 19 grain load, I may have to go with 2400. I see I still have to tap that dadgummed rear sight over a wee bit more.
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Originally Posted by dubber123
There is not much that irritates me more than sights that need to be drifted WAY off to one side. It tells me something wasn't screwed together straight.... It would appear they knew what they were doing 90+ years ago. Nowadays on the other hand... 
38-40
Another interesting side bar is that I've become convinced that potential buyers whether they realize it or not simply have been brainwashed into thinking the 44-40 is much more macho than the 38-40... at some level thinking the 44-40 is a true 44 cal and the 38-40 is a true 38 cal (or even 357 cal 
