Try this bud.....it worked for mine. Take him out and have a partner with you. Have your buddy hold a 22. Get him all excited with a game of fetch. After the 2nd or 3rd throw, make a big deal, maybe even give him a treat. Then the next time, just as you throw the bumper or toy, have you friend (who needs to be at least 50-75 ft. away from you) fire a shot BEFORE the bumper hits the ground. Then do a couple more without shots. Then a couple more with a shot.

Make sure it is COOL when you do this and don't let the pup get heat exhaustion.

Hope this helps!