I bought a g23 used from a coworker. The person he had bought it from had put aftermarket Nightsights on it, and they are HUGE. Almost foolishly tall. After 300 rounds between myself and friend I find the gun shoots about 5" low at 30ft. Could lower sights fix this or am I crazy and just need more practice? I own a 22 and 27 with factory sights and shoot fine with them.