Beyond the 25 20 mark on bottom of the barrel is marked 3 X next to the tenon threads. Is that a date code?
No
Without a serialized receiver it’s impossible to determine the date that the gun was manufactured. One can narrow it down a bit as the Winchester Definitive Proof appeared on barrels after 1905 and I believe that the were three different barrel addresses used during the 1892’s fifty year production run.
