Interesting. I have a Winchester 94 which is a 30-30. Are you saying it also shoots 44 magnum? The bullets look to be about the same diameter. I’ve never shot either the 30-30 or the .44 mag revolver so I’m just learning about both.
Also available in .44 Mag.
As an NRA instructor, I recommend that you not even touch a firearm until you understand what a cartridge is, what caliber means, and the fact that every time you pull the trigger on a firearm you are in essence setting off a bomb mere inches from your face.
DO NOT fire a 44 magnum cartridge in a gun chambered for 30-30. The cartridges are NOT “about the same diameter”. The CASE may be, but the bullet in the 44 is .429 as opposed to .308 in the 30-30. The larger bullet will plug the barrel and the expanding gas (with no where to go) will blow up your rifle. This will cause damage, to your rifle, and potentially your hands and face (remember the comment that you are setting off a bomb mere inches from your face). People have been killed by exploding firearms.
Again, I recommend that you NOT FIRE ANY FIREARM until you take the time to learn about them. Failure to do so is equivalent to giving a 3 year old a stick of dynamite and lit road flare. The resulting damage is inevitable.
The Winchester 94 has been chambered in many calibers, 30-30, 32 special, 44 mag, .357, 38-55, 44-40, 38-40, etc. NONE of these calibers is interchangeable.
Here is a pretty good place to start: http://www.corneredcat.com/article/ammunition/caliber-confusion/