Ed, yes it can be cut with a hacksaw, easily. It’s so hard, it’s brittle. Put a stick in a vice marked where to cut, take a few strokes on it with a sharp hacksaw until it’s clearly notched, then grab the protruding end with pliers and it will snap right off.
For a brief update: I’ve now completed two arrows with tungsten inserts, both having started at about 460 grains, lodgepole pine hexshafts with hardwood footings. With 190 grain points these arrows had something like 13% FOC. With 3.5″ tungsten FOC went to just over 20% and total arrow weight a whopping 835 grains. Spine was unaffected and it still gives perfect arrow flight, though it does have the excessive trajectory you’d expect at that weight from a 55# bow.
The second shaft I used just 1″ of tungsten and got 18.65% FOC with a total weight of 748. Perfect arrow flight again and trajectory was acceptable at 20 yards but still more than I need (looking for 650-700).
To date, thus, I consider this a failed experiment given the cost of the drilling jig, $30, which has yet to provid a perfectly centered hole, the cost of the tungsten, and all the work. It also complicates tapering the shaft for a head.
If a guy still wanted to go this route — which should provide a far stronger shaft end than Woody Weights — he will need to start with a really light shaft. Since I have some tunsten left and bought the jig, I’ll next try it with po cedar.
Yes, you can buy it in different diameters, and in blends such as t-moly, t-copper that may be cheaper but not so heavy. dave