I am somewhat sceptical. Outside of the the spin from Horton, and the media writers echoing their claims, there appears to be no independent information as to what "Hortonium" actually is, not even an SDS statement.

I agree that much of the anti-lead ammunition movement is based on zealotry served up to regulators so lacking in knowledge they'll jump on any bandwagon. Unfortunately it is highly likely that the anti-lead brigade will get their way and projectiles (both shotgun and rifle) containing lead will be progressively banned. While I still use conventional projectiles for my centrefire rifles, I have loads developed using non-lead alternatives ready to use should the day come.

If they have indeed come up with a lead substitute with acceptable performance and cost then much kudos to them. However I would wait to see more detailed information and independent testing. At the moment it looks more like what the IT types refer to as 'vapour ware'.