not really sure on the weight of the 2 cores but i am guessing that they are pretty close to the same. the old cores in the bomb series are bigger but they also have one side hollowed out to place the mini nugget inside it. but with the new core nothing has been hollwed out cause it doesnt have the mini nugget. so that is why i am thinking they weigh roughly the same. i have both the colbat bomb pearl and the massacre drilled exactly the same and the massacre is more angular. if you are thinking about buying a massacre do it you wont be dissappointed
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