[quote=@Shadow Daedalus]
[@vancexentan] That's why I ran it past you first.

My justification is that the elements my character is aligned with are Fire and Earth, which deal with energy transfer and embedding respectively. The process itself is similar to reinforcement (a simple magecraft that even Shirou could handle), but instead of the mana strengthening the object, it instead embeds his origin into the object. Because it is his origin that allowed James to use his unique magecraft, I figured it wouldn't be too much of a stretch.
[/quote]

Yeah, but usually (Kiritsugu not withstanding because his was a Mystic Code) having unique magecraft derived from an Origin usually means your Origin [i]is[/i] your Element, like how Shirou's Element and Origin are both "Sword". Plus, and this is just me, while James does already have a projectile version of his Void magecraft, I imagine it doesn't travel at supersonic speed like a bullet does. A gun that can make Servants into swiss cheese is exactly what makes Lancelot so broken, and it would probably make for some pretty nasty friendly fire too if James ever misses what he's aiming for and hits one of the Servants on his own team.

Of course, Servants can deflect bullets, but I imagine getting a hole shot in your favorite Noble Phantasm isn't something a Servant would be too happy about.