My neighbor just bought a Barnett Predator xbow and is having problems. The screws on the scope and i think some on the bow are loosing after about 15 shots. Is this a problem with them?

Who else has had problems with the predator?

You just need to do a search here and you will see volumes written about Barnett and the problems!

Most any tool that gets the vibrations that a bow gets, needs thread lock on the screws.

Use Blue Loctite on any thing that has screws. All crossbows are powerfull hunting tools with lots of torque and can work things loose. Most use the loc tite to fix the problem. Buckeyefootball