first off yes any automotive store should have the correct o-rings just take one of the spares that comes with them and just match it to the ones at the store. Next if you want to test the rage in a target I have found that you have to push it through the target unscrew it then pull the arrow out. I tested it and tested mine to check to make sure the BH opened all of the time but yet I still hear of people saying there haveing issues with them.