Shell Casing and a lipstick tube?

[fyrffytr1]

Would someone here kindly help me with these two items. The first is an unmarked shell casing and the second is, I believe, a lipstick tube. The casing's mouth is deformed so it is hard to get an accurate measurement but it is about .75". The base is about 1.16"s and overall length is about 4"s. There are no markings on the base.
The second piece is a lipstick tube, I think. The knurled base would unscrew if the cylinder was round and there are three small holes around the base. It is marked "Pat Appld For".
Thanks for any and all help.

 

[fyrffytr1]

A couple more pictures.

 

[NOLA_Ken]

Shell looks like the standard 20mm used by the US, look for 20mm Vulcan round on google images

 

[WaterScoop]

Sweet find!

 

[BIGSCOTT]

The bottom picture in the first post is a model t valve stem cover

 

[BosnMate]

The bottom picture in the first post is a model t valve stem cover

I knew I'd seen that before.

 

[BosnMate]

Here are a couple of photos. Comparison of sizes of ammunition, and a twin 20 on board ship from back in my day, The navy still uses them, but the gun now days is belt fed and totally different looking, and there is also a 20mm gatling gun. The ammo ranges from .22 long rifle up to 20mm. .50 caliber Browning machine gun is next to the 20.

 

[fyrffytr1]

The bottom picture in the first post is a model t valve stem cover

I am not sure about that ID. The piece in question is two part with a base that screws into the tube. Why would it have a base if it was a valve stem cover? It is also very light weight and probably made of aluminum. I have an early valve stem cover and it is much sturdier that this piece.