I agree, WW is probably wheel weight. Could be "MM" but don't know what that would be
B might be babbit
TYPE is probably lynotype
All 3 of these and your shot is too hard for muzzle loaders, trade it to someone who casts for centerfire rifles or start casting "boolits" yourself
AS a general rule, if you can scratch it with a thumbnail its OK for muzzle loader round balls or maxis.
Too hard lead can be a bearcat to load from the muzzle unless you are laoding undersize balls in a smoothie.
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