>>64274409
A helical mag's spring just pushes the rounds to revolve around, and then the helical ramp redirects that circular motion to be a spiral path for the rounds, with the rounds' front and back sliding along it. In the case of feeding from a forward protruding helical mag, it's the bullet point dragging along that ramp. That's surmountable and some functional prototypes are likely, but it surely presents some additional challenge, on top of helical mags having a dubious track record otherwise.

Thinking about that, if it is a big issue, maybe the calico style rearward protruding helical magazines would make more sense for pointed bullets, rather than the bizon style forward protrusion? Then the bullet points would only be contacting the ramp in the loading process where the spring pressure can be relieved and there isn't much friction to overcome, and the feeding process under full spring pressure would slide the rear of the rounds along the ramp, not the bullet points.