I'm no expert by any means, but last time shooting AR's, I used a pair of padded, fingerless gloves which REALLY helped with my hand/index finger getting rubbed raw by the trigger guard area. Since fingertips, to the 1st knuckle, are open, I lost no movement or feel whatsoever.
I kept them on while shooting a couple 1911's and even a .38 snubbie. It was actually a treat to use something for the pistols, and that was the first time I did so...but not the last.
thisI have PIG FDT Alpha gloves.
These sound like what I want. Having a fully covered index finger doesn't work well for me. Just haven't benn able to find any.