Your Marlin model 21,which was the straight grip version of the model 19 shotgun,was made from 1906-1907 by the Marlin Firearm Company.
I can say that the Marlin model 81DL was made from 1940-1965.This was a promotional model,made by Marlin.
The Marlin Model Golden 39A is the oldest and longest continuously produced shoulder firearm (rifle) in the world.
1950.
None,they are one and the same firearm.
It shouldn't. You should only use products manufactured for your firearm on that firearm.
I can say that your Marlin model 336CS was made in the year 1984.I would look to Marlin,s own website to get any more info on your model of Marlin lever action rifle.
Your Marlin model 81DL was a promotional model that was made by Marlin from 1940-1965.These range in price from 65-100 dollars.
The 2 letters AB indicate that your Marlin model 336 was made in the year 1966.
The letter E ahead of your serial number indicates that your Marlin model 336 was made in the year 1948.
Plug the phrase "Marlin Model 99M1" into Google, and you'll find a wealth of data and sites relating to this firearm.
The letter W prefix to your serial number indicates that your Marlin model 336 was made in the year 1963.