I am ordering mold from accurate molds to cast a bullet for my 12 bore A&N rifle. The bullet will weigh over 700 grains and be .75 diameter. Should I order this mold in aluminum, brass, of Steel? This is the mold, it will be enlarged to .750. The bullet weighs 700 grains in WW. I plan on using much softer lead so it will weigh more. Thanks, Ed

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