No such sn in the SM Ace range
No such model number desgination was used by Colt.
The Colt Service Model Ace .22 Long Rifle with the serial number 51046 was likely manufactured around 1949. Colt produced the Service Model Ace between 1947 and 1950, and your serial number falls within that range. For exact dating, you may want to consult Colt's factory records or a reliable Colt firearms historian.
you will need model name.
made by Colt about 1916
Proofhouse.com has Colt sn data
Proofhouse.com has Colt sn tables.
That Colt .45 government model was made in 1918.
Proofhouse.com has Colt sn tables.
1918
By model and serial number. Go to proofhouse.com
Impossible to answer without knowing what model you are referring to.
Impossible to answer without knowing what model it is.