First of all Hornady makes cartridges for it @ about $27 per box of 20. This is a bit cheaper than what you could build less than 200 rounds for, and I doubt you'll ever shoot it more than that.
And, I believe, the lead bullet molds for it are at 300 grains( see
www.buffaloarms.com for current Lyman mold for it). As for loads, see Ideal Handbook # 40 (or others in the 1930s, 40s, or 50s). Powders listed are 2400, 3031, 4320, and Unique. I wouldn't trust another's word for the exact loadings... read it for yourself! The .405 is underpowered for dangerous game( buff, Rhino, tuskers, etc), but is way overstrength for deer and blackbears. In some cases the receiver sight that may be present on your Winchester has great value as, to date, no one has reproduced another for that rifle (I think).
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