The American Bradley stores rounds in a separate armored compartment behind the loader. If the compartment gets hit and the rounds cook off, the blast is redirected out the top of the tank away from the crew compartment which makes the vehicle much more survivable.

Don't you mean the Abrams tank?

https://en.wikipedia.org/wiki/M2_Bradley: "The use of aluminum armor and the storage of large quantities of ammunition in the vehicle initially raised questions about its combat survivability."

https://en.wikipedia.org/wiki/M1_Abrams: "The M1 Abrams...introduced several innovative features, including a multifuel turbine engine, sophisticated Chobham composite armor, a computer fire control system, separate ammunition storage in a blow-out compartment"

In the Abrams shells are stored in a separate armoured compartment and are individually fed to the loader as needed. The loader might have a shell fed and in hand ready to reload the gun, so that's one shell in the compartment at the ready over the one loaded in the gun at any given time. There just isn't space for more shells lying around.

> a dozen of rounds

This made me happy. :)

(In Russian, numeric determiners 2-4 place the noun in genitive singular and numeric determiners 5+ place the noun in genitive plural. One book, two of book, three of book, four of book, five of books.)

Czech is exactly the same - jedno pivo, dvě piva, tří piva, čtyří piva, pět piv, šest piv etc ...