I think you mix up bubble-canopy with modern canopy.
Bubble meant rather to have no structures around you, so you can look around with unblocked vision. You have that in IL2 already. To be able to move the head sideways further than in another cockpit, you need a modern canopy that really has a bubble-like shape sitting rather on top of the hull like this:
That was not used in WW2 though, AFAIK, most likely due to manufacturing limitations.
To the second part of the question:
That depends on how fast you turn. The bullets leave the muzzles with a velocity of well above the speed of sound. You need to pull pretty hard to not see the bullets after you fired them, if that is what you are asking for.
Unless of course you turn so hard that your guns bend down...