You can disregard the CCI 22 LR on the left – until I looked at the photo, I thought the headstamp was an O.
The 22 Short in the middle, I had identified as Union Cap & Chemical, but would appreciate confirmation. The only photo I found of a UCC headstamp showed a slightly different cross.
I wasn’t sure about the 22 Long on the right, and a google search for “a headstamp” was not particularly productive.
Thanks in advance,