Any one that goes bang every time. I assume you mean limited-10 class, ten round mags and iron sights. Get good mags and practice. I saw too many people yesterday that couldn't make their gun function. Personally I was doing my poor shooting with a 57 yr old USGI gun that was way more up to the task than I was. Only mods are sights, trigger, ambi since I'm a lefty and Wilson mags. I'll say it again, Wilson mags! Get a steel basepad, they don't break and the mag drops nicer and lands on the basepad.