How old?
my great-grandfather's lever action .30-.30. model 94 winchester.
my dad said its around 50 years old.
Well, let me see.
I bought a brand new rifle last year. When I hand that down to my kids or grandkids, it will be at least 20 years old. I'm pushing sixty. If I had bought that rifle back when I
should have bought it, it would
already be twenty years old, and my kids would get a 40-year-old rifle.
I have an M1 Carbine that was made in ~1942, contemporary with my dad's service. That gun's 65 years old.
If my grandfather had handed down a rifle, it would certainly have been from around that time, or earlier. So, a "grandfather" rifle might well be more than 70 years old.
If my grandfather's father (my great grandfather) had handed down a rifle, it would very likely have been
at least 70 years old. Likely more than 80 years old.
I don't know when your great grandfather lived, but 50 years is very likely on the low side.
I don't have the actual dates, but the "model 94" (if I understand it rightly) gets its name from the last two digits of "1894" -- meaning that design has been in production for more than 110 years.
If you wanted to nail the actual age of this rifle, you would need the serial number. There are places online where you can check your serial number against a list that tells what years made what ranges of numbers.
Got a picture of this rifle?