The ammo crates are pretty universal. From the below set, the most common I have seen used during WWII up through current times, is the crates to the right and the individual black tubes in the center.
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For the boxes, the far right one w/two bands opens at the top. The one on left is a version that opens on the end.
The black tubes (called tootsie rolls - looks like the candy) comes two inside each box. The five in the middle of the boxtop are the most common type I have seen. I'm not sure about the three on the left with a larger endcap. Inside each tootsie roll is one round (two piece shell and canister, with powder increment bags inside the canister) of 105mm ammo.
The three pack round containers (wood box and tootsie rolls) I believe were used as airborne containers since they were lighter than the wooden boxes.
You can see the tootsie rolls, wooden boxes, and an open round in this picture.
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