I am happy to report my Sinanju is currently holding his Rifle/Bazooka combo up at a 45 degree angle just fine. The left arm is toting the shield/double gatlings/bazooka combo and can bend it's elbow up 90 degrees and keep it there. You may have different experiences based on your personal build, but so far, it's held that pose for a few days now (just finished it).
Until Next Time: Happy Building!
Want to Buy LM Leo or Taurus from Gundam Wing, built or unbuilt! Willing to pay big!