Alan,
I have been doing load development with the 300 Woodleigh. I can give you the information I have so far. I used the 300 grain Winchester loading in the late 70's on elk and moose with great success. Obviously, the woodleigh bullet is a better one.
I use Winchester cases, CCI large rifle mag primers in this caliber.
IMR-7828 70 grains at 2512fps shoots into .95 inch at 100 yards.
IMR-4831 65.2 grains at 2517fps shoots into .78 inch at 100 yards.

I am looking forward to using this bullet on bear in the spring!!

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