$ gpg --list-packets abc.asc 
# off=0 ctb=89 tag=2 hlen=3 plen=284
:signature packet: algo 1, keyid 250B7AFED6379D85
        version 4, created 1467148252, md5len 0, sigclass 0x00
        digest algo 10, begin of digest ba d8
        hashed subpkt 2 len 4 (sig created 2016-06-28)
        subpkt 16 len 8 (issuer key ID 250B7AFED6379D85)
        data: [2047 bits]