Early rolling blocks and the years of the model 12 "pump" were not marked, need a good description to identify.
Google Remington scoremaster model 511. Several websites have information on this .22 firearm.
Remington never made a model 22, a model 12 pump (1910), or a model 24 semi-auto (1925).
it is 56 Remington rifle model
1920
Remington didn't make a model 54, Winchester did but not in 22 (that I know of), Marlin model 54 is a shotgun.
You need to find a good gunsmith
The Remington 22 special (used in model 12, 121, etc) is the same as a 22 WRF Occasionally Winchester or CCI will make a run of ammo but Remington doesn't anymore. Your have to search gun shows if you want to find some.
It is a 22 Long Rifle.
It is a Remington Model 12 .22 cal. pump
Look at the date code on the barrel. Details on the Remington Society of America, manufactured date link.
Check Remington Society of America Service/Link page: http://remingtonsociety.com/rsa/service
Remington never made a Model 1905 22 rifle.