Some of you may have noticed the gap between the trigger guard and grip on the AR15, and not in a good way.
For me, it has never been an issue, just because of the way that I hold the grip, personally, but if it is an issue for you, there are a couple of solutions.
The Gapper is a neat little product that fills that gap with a piece of rubber designed to fit in that space. They often come with the purchase of an Ergo Suregrip.
The other one that I am aware of is the Magpul winter trigger guard. These were intended first and foremost to create extra room for a gloved finger to pull the trigger. However, they also found the solution to the “gap” problem with this clever design.