Exflatlander - Does that mean your now on a hillside?
I think the .307 is the best of the three "modern" lever cartridges. I would start with 40.0 grains of IMR 4064. thats whats proven to be the most accurate in mine. I like the Speer 170 the best as the paper ballistic coefficient is the best. I have had very good luck with the Speer on deer from all angles. The Sierra 170 has a little softer jacket. It is accurate at 2300 fps+ but it opens up pretty quickly. I have found the Hornady just as accurate as the Speer and just a little tougher in construction, perhaps due to the interlock construction.
Do not overlook the 130 Speer in the .307 for bragging groups. The 130 will shoot one inch groups in my rifle. Not every time mind you! But it will do it if I do my part. It is the only bullet that will feed through the magazine that I have found that wiill shoot that well.
The .307 can be a little peak pressure sensitive. Watch maximum loads carefully and work your way up carefully for the last one and one half grains. If you get a kick in the lever STOP. That is the lever trying to unlock. Some published loads will kick the lever pretty hard. I have heard that different guns have different max loads capability.
I have had more one shotdropped in its tracks kills on deer with the .307 than any other rifle. That doesnt mean that others wont do the same, its just that I have had that kind of luck with the .307. That said, I dropped a nice six point buck in its tracks Sunday with my .444 Winchester!
Dont overlook Varget in the .307, it gives very uniform velocity with low extreme spreads. Varget is also quite predictable when increasing charges.
I began with starting loads published for the .308 and lowered them one grain.
The .307 can be a little "peaky" as maximum loads are approached but Varget doesnt seem to surprise you. In other words a one half grain increase doesnt loosen primer pockets or other scary things like that. The .307 seems to have a habit of kicking the lever when pressure gets high. A sure sign to back off. The .356 will do this but not to the same extent as the .307.
The problem with unpublished data is that we are all a little nervous sharing! I had no problems with starting loads listed for the .308 in my rifle.
I know there are people out there shooting the .307 Improved in lever actions because I have seen pictures of the cartridges in several magazines. Anyone on this board doing that?
I was just talking about my Varget loads with a friend and he said... "say didnt you get your starting loads from the Fouling Shot". Like I said earlier, I wish I'd have thought of that!
If you are not a memeber of the cast bullet association you should consider joining. They publish postal match results with lots of loading data each month. Lots of new powders and surplus powders are used in these matches with reliable results.
A good group with a "Jillion years" of collective experiance. They also have a web group over on Yahoo groups.
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