I did manage to get a few test firings done today. I had to play with the length just a little to get reliable chambering and still allowing ejection. A lot of times, a round can be chambered, but it just doesn't want to come back out to have a safely unloaded gun! [:s] So, I ended up trimming another .008" to an even 1.50" total length. That still leaves 1.442" of usable case.
I played with a few loads that have performed well in the old cases. For some reason, I can't load quite as long as I have in the past, but the 180 gr XTP and 180 gr Rem JHP chambered well at 1.90" with 11.0 gr of 800X and a CCI 400. The large firing pin hole in the receiver indicates this is about as far as I want to go with this load, at this length.
I had mentioned to George (gstanfield) that I wanted to try some 2400 loads I saw in the old 4/85 Hercules Reloader's Guide. They're .357 Mag loads, but I figured that would make a good starting place. The first load was 16.5 gr of Alliant 2400, CCI 400, 125 gr Golden Saber at 1.798" OAL, which is 1.0 gr under the manual max load. Then I increased to 17.5 gr, which is the manual max load. Since these had all functioned without a problem and the primers looked good, I full length resized again and upped the load to 18.0 gr. Everything stills looks good, but I think I'll put these through the chrony before going any further. If the book hasn't lied too much, these should be well over 2000 fps.
Here's what the brass looks like after being resized 6 times on just the two center pieces (the last time was "neck sized").