Ok, so I did the unthinkable, I pulled apart an original round to see what it was actually made of.
This was a short, they cost about $1.50 each at gun shows, easier to find than the longs and they all used the same bullet. This one was stamped with a D, so Dominion ammo, the US stamped one I am not cutting apart.
The original bullet weighs in at 65gr, the powder really looks to be BP, I have not shot any of these yet but I have BP and this looks like BP, just a cake of BP that comes apart as dust, hence why I think FFFg may be too coarse but that is for a different section. The bullet measures out at .254 with the lube and .251 when I scrape the lube off. The lube grooves exist, there are 3, they look like cannelures as opposed to lube grooves, not deep at all, maybe 10 thou. I measured the bullets that I just knurled, they came out at .254 to the high points, most likely .251 at the low points still, very similar to the original with a little less depth on the groove.
The cast bullets as I have them are .259, way too large for that bore, the sized bullets are .250-.251 and do not fall into the bore, with the knurled bullets at .254 and able to take lube I think I will be ok.
I tried rolling the bullets into the lube, it works, I can smear it on as well before I load, the 50/50 mix is a hard lube but so is the original, either that or it dried out.
Hopefully this week I can shoot a few original Longs, Shorts and my loads, it will be interesting to see what velocity I run into.
I will have a pretty detailed thread in the rimfire section and probably link to it in the reloading section if I have some success, maybe help a few guys get their old 25 Stevens running again.