Tungsten

[overkill]

Its also very expensive and hard to machine. It's high density makes it handy for compact counterweights in spinning weapons and is used in the RioBotz drum spinners.

[jay]

Its also very expensive and hard to machine. It's high density makes it handy for compact counterweights in spinning weapons and is used in the RioBotz drum spinners.

We mill the corners of box section, insert tungsten pellets in the created groove, then weld over the top creating re-enforced box section..

Its a government approved bar we use on prison windows.

Was thinking of doing something similar on a spinner to give more weight for a greater impact.