This skill is one of the slowest leveling, minimally rewarding skills in the game. I would even go as far to say including the skills that aren't even integrated yet.

I am level 46, 662 raids under my belt, and get into a lot of gunfights ~1500 kills atm. I bring tons of extra ammo and mags to load and unload throughout the raid. As we speak, my "mag drills" skill is currently a mere level 2, with 26.6/30 skill points needed to get to level 3. With this level, I receive a 1.2% buff to mag load/unload speeds, along with a measly 0.2% buff to capacity check accuracy. Pretty comically abysmal rewards.

As I said, I perform the activities that level this skill quite frequently: loading mags, unloading mags, checking mag capacity etc (all during raid).

Out of curiosity I went into a raid packing a bunch of empty PP19 magazines that load fast with some stacks of PST-GZH. I sat there loading about 180 rounds one by one, just to notice my mag drills went up between about 0.1-0.3 skill points. The worst part is that I literally still had the blue up arrow indicating that skill's growth still has the initial bonus. I hadn't even reached diminishing returns yet.

I proceeded to take 5 minute breaks after hitting diminishing returns and repeating the whole process. I only saw about 1 single skill point received after a solid 1000+ rounds loaded, unloaded, checked etc.

There is no way this is how the skill was intended to function. If it is.... then I don't know what to even say. Take it out of the game or fix it