The manufacturer markings are who made them. They are abbreviations of the full names for the company's full name. For example, Inland Division of General Motors would be Inland Div. The markings are on the barrel but it is way easier to find them behind the rear sight. I'm sure you know this, but the rear sight is behind the reciever, which it the sight shaped like a circle. if you want to know when it was made, post a new question with the manufacturer marking and the serial number which is located under the manufacturer marking.
Go here - http://www.fulton-armory.com/M1Carbine.htm
No, they weren't.
Non firing replica M1 and M1(A1) Carbines are made by Hudson, airsoft Carbines are Made by Marushin, they go for around $300.
IBM was one of the makers of M1 Carbines- along with companies that made postage meters and juke boxes.
No.
It should if it fits on other kinds of M1 Carbines.
All military M1 Carbines were made between 1941 and 1945.
M1 carbines are semi-automatic and M2s are full automatic.
Planefield
No. M1 carbines were made semi-auto only. M2 carbines had a selector lever for simi-automatic or full automatic. Iver Johnson never made M2 carbines.
Go to CMP to find M1 Garands and M1 Carbines. Also, go to http://www.m1garand.com, they will tell you everything...
Sharps Carbines were built from 1850-1875, while M1 Carbines were built from 1942-1945.Sharps Carbines were used until 1881 by the US Army, M1s were used until 1975.Sharps Carbines were single shot, while the M1 took a clip of bullets that carried either 10, 15, 30 or 60 bullets and either Semi-auto or full-auto.Sharps could shoot about 500 yards while the M1 shot 300 yards.The Sharps rifle is a very old gun while the M1 is way newer.