Use 9mm casing with primer removed on a 100 grain point. Take a hack saw and cut an X on the top.
I heat up the casing and drive it on a point, let it cool, and then glue it on the 100 grainer. They work so well and that X helps deliver energy, but grabs grass and brush. I have even use a screw driver to expand the X's a bit.
Keeps you in the weight ball park as a 9mm weighs about 64. Never weighed one without the prime and after I cut in the X,b ut it would seem to get ya pretty close. I can use just a little heat and remove the 9mm case to get my tgt points back