Rear Turret Ammo Rail Questions

Hi All

I’m drawing up the ammo rails that fed the rear turret on the Stirling, however something isn’t right.

I think that the rails have very roughly the profile as shown in the attached renders but if so then the rounds would not lie parallel to the rails but lie with the lead end pointing up slightly – no reason why it shouldn’t but it looks wrong. I’ve drawn one round perpendicular to the rails and the other as it looks like gravity would want it.

Also I know my round is correct but the rails are just dimensioned from a photo with a ruler in and so I can’t really get the metal work sizes right especially the curves. Equally I don’t know how ‘loose’ to make the rails, are they nearly tight on the rounds or quite loose?

So does anyone have any accurate dimensions for such rails and/or how did the rounds sit in the rail?

Cheers
James