I have a nearly new G20 (3rd generation) that doesn't shoot very well. I'm getting 12" groups at 25 yards, shooting over a rest. The ammo is Winchester 175-grain Silver Tip Hollow Point. I got somewhat *worse* results with Remington 180-grain Metal Case. I know that I might not be the best shooter in the world and the gun might not "like" this ammo, but I think there is more to the story. Any ideas on what I might do to improve the accuracy? I'm not expecting miracles. If you've covered this already, please let me know where I can find the info. Thanks.