The Gauntlets of Force translate movement and mana and Will into precise movement at a distance. We want a lower-complexity, lower-range, lower-power version of that on our gun barrel.
I added mention of the Rabbit's Foot as an inspiration for the "calculating and making minor adjustments" bit, as NUKE recommended on Discord some time ago. Even if we don't understand all of it, we still have it *and know how to make them*, thus we know something about it. Enough to help with another spell? I hope so, otherwise why bother giving it to us at all if we need to waste an entire action to figure it out before making any meaningful use of it?
Evidently he, you, and I disagree somewhat on what is a reasonable stretch and what is not. We absolutely need this rifle, otherwise our guys are going to be glorified trench-diggers only slightly faster than people with shovels, with a thing for trench coats and steel wire, with no realistic offensive options whatsoever. With this rifle plus a (lightly modified to give us the proper range?) set of binoculars for spotters, we could at least deploy elite sniper teams to make a mess wherever necessary. Or just this rifle and we can deploy a more-effective-than-average infantry unit, etc.
I absolutely want to do Mirage, and am considering voting for two designs this turn to get it going, before using next turn to wrap up as many projects as we can/as are necessary. I just worry that Mirage may be a little too difficult for an Evocation, and will require highly-experienced casters or a quick remake into a [multi-caster] Sorcery to actually be field-deployable.