When you load a Mosin without a clip for the ammo, the animation plays where the player puts every bullet into the rifle manually. This is fine, after that however it becomes impossible to put additional bullets into it before all five have been fired. This would ONLY be the case if you were using a clip, not if you manually reloaded.
- Legacy ID
Even with the clip you can manually reload single bullets. The clip just holds 5 bullets for faster reloading, after reloading you take away the clip, its no part of the weapon just a helper to load up faster.
Dogmeat is completely right, if you pull back the bolt for reloading the bullet inside the barrel can be put down deeper into the "magazine".
Edit: @ guest: Seems like you would have no idea ;)
@guests: the Mosin uses stripper clips. These hold 5 rounds, you clip the thing to the gun and then you push the rounds from the clip into the magazine of the gun. After that, you take the clip away and close the bolt, the clip never enters the magazine. You can put additional rounds into the mag at any time after that, it makes no difference.
It isn't like the en-bloc clip of the M1 Garand, which is pushed into the magazine and ejected when empty.