Before posting as a bug, I wanted to make sure I understood how range modifiers are calculated. The situation I tried myself is a simple one, Unstable Injectors and Gunnery Implants vs a Stock setup on a Paragon (so it has +100% to weapon range from the Advanced Targeting Core). It looks like Gunnery Implants are only adding 1/2 of the 15% bonus, so it doesn't counter the negative effects of Unstable Injectors; nor do you get 15% additional range without Unstable injectors, at least on the Paragon.

Paragon with Tachyon Lances (1000 range default)

Stock: **~2000 units**

Unstable Injector: **~1700 units** (about what is expected - 2000 * 0.85)

Gunnery Implants: **~2150 units** (half of 15%, which is unexpected on my behalf)

Unstable Injector & Gunnery Implants: **~1825 units** (this looks to be the range of 2150 * 0.85)

I measured the length of the firing arc with a ruler, and then scaled by a constant (eg stock range was 18.2cm, and since the range should be 2000, 2000/1820 gives a constant to scale the results).

The best way I can make sense of it is that Gunnery Implants isn't compounding with the Advanced Targeting Core of the Paragon and just adds a flat range calculated from the base range of the weapon.