That seems to be the idea, but the gun barrels are clearly longer than the claw section in the top part of the image.
It also seems like a bad idea to put the ports the bullets are fed through outside the gun, and facing outwards in the direction the "turtled up" crab pose faces towards the enemy, since that would just mean you need to aim for the ammo port to start an ammo explosion. That hose from what seems like a large rear-mounted fuel tank also looks like a juicy target.
EDIT: I can't believe the first time I was pointing out the weak points on the giant enemy crab, I forgot to mention that hitting them would result in MASSIVE DAMAGE!