Gun ports
Unknown.
Magazines and the very few firearms that use clips are used to hold ammunition.
nerf magazine drum
On Sailing ships of old. The "Gun Deck" (Cannons) was the deck just below the top deck. The Cannons were faced out of the side of a ship through port holes called "Gun ports."
Gun shop, gun shows, e-gunparts.com
You will have to call to find out.
The "holes" are generally referred to as ports. They assist with recoil reduction.
Paper clips in the holes
Three Holes Two Brads and a Smoking Gun - 2014 was released on: USA: 2014
You can, but only with an add-on of some sort. The Flip Clip and Bandolier Kit both carry two clips.
trenches were ditches dug for protection of troops from machine-gun fire and bombs. they were also called "fox holes"