Welcome to the boards mate, I see that you have a semi-decent grammar level. But just try to sound as professional as possible. As far as you choosing the United States Marine Corps in hopes to be a sniper just know that the physical requirement to become one is one of the hardest physically demanding spots to join, also I think you need to have a little rank before you can join (E4 or something.. I'm probably wrong on this information).
Anyways, just don't go in with the mentality of "I'm going to be a sniper" because I had that mentality about the Marine Corps for a while, and after talking to a few (Phridum is one, send him a PM) as well as looking at the PST (Physical Screening Test) requirements I could tell you that it's nearly impossible to reach the standards without vigorous training. I don't know the specifics on all (I'm sure Wikipedia could tell you better than I) however I can tell you that it's just about double what the Navy SEAL's require for your PST.
Anyways, on topic to your JG Bar. Those things are garbage, if you want to experience the sniper role build yourself a VSR-10 (Tokyo Marui G-Spec) and put the M40A3 stock on it. That's about the closest you'll get to an actual USMC Scout/Sniper rifle.
With that being said, this topic is moved to the Clone Section.