Weird Trains in WY

OK im a little to ATS,So forgive me if this is old. I used to Live on Ft.Collins CO wich is basically in the Rockies. One Day we went to pick up a new dog From Cheyenne WY, we left in the early Afternoon and left cheyenne late evening. Somewhare near the CO WY border this train moving very fast had the srangest looking cars behind it they were all smooth and wernt rectangular but weird shapes:pentagons and stuff like that, also at our home we'ed see lots of flatbeds with missle or submarine shaped cargo going towards the mts sometimes with troop carrying trucks ffor accompaiment, often this stuff was seen late at night. but for the trains im sorry for no links or pictures but would like to know what they might have been carrieing