With any firearm of that vintage I would NOT fire a smokeless cartridge thru it.The guns of that time did not have the heat treatment that is available today.These were made during a time when only blackpowder was used as a propellent in gun cartridges.With the cowboy action shooting going on at area ranges today you may find 32-20 blackpowder loads available.
No you cannot, the steel and manufacturing techniques in the late 1890's cannot handle the pressures of modern 'smokeless' rounds of today. The marlin 1889 and other firearms of that period fire blackpowder cartridges. And a number of ammo companies today sell blackpowder rounds for the Marlin 1889 and other firearms. You can go to midwayusa.com and other internet ammo sites to get it. However...before you fire any antique, get it checked over by a good gunsmith to make sure it is mechanically and otherwise safe to shoot.
the serial number 21171 would be from late 1888, the 38W stands for 38winchester also known as a 38-40 caliber. this gun will be either a late model 1888 marlin with top shell ejection, or a very early 1889 model with side ejection, also the model 1889 would be marked marlin safety on top of the reciever. in either case this is a antique black powder cartridge firearm and should not be shot with modern smokeless powder ammo, due do stronger ammo pressures and weaker steel that was used in the guns of this period.
The marlin model 1893 rifle was only made from 1893-1936.It was the first Marlin rifle made for smokeless powder.I would say that your rifle was not made in 1946 though.You may have a Marlin model 36 rifle,which would handle any commericial made ammo on the market today.
marlin 35 cal. lever action. rifle/ Marlin makes the rifle ,but not the ammo for it.
MODERN 22 LR ammo is smokeless and "greased" even though it in not marked that way. It was to distinguish it from older black powder ammo, no longer made.
winchester
MidWay USA among others that come up when you do an internet search on 32 20 ammunition.
You will have to contact Marlin to find out.
buffaloarms.com. They are expensive.
lead ammo
The winchester 25-35 Cartridge CAN be safely fired in a 25-36 Marlin caliber firearm. They are similar cartridges, the Marlin is a bit longer. For that reason the Marlin ammo cannot be fired in the Winchester.
The marlin model 781 was chambered for the .22 long rifle.