M1 Carbine Stock Question

[painter777]

No IP were accepted. Their contract was terminated by Ordnance. Saginaw Steering Gear of Saginaw, MI a Div of General Motors was already building Carbines, marking S.G.
They were awarded and took over the IP contract on April 1 1943 in Grand Rapids, Mi. Becoming known as Saginaw Grand Rapids, marking S'G' and took over any useable parts and the Serial numbers that had been assigned to IP. Your Serial number was originally assigned for IP and a very early one at that, but your Receiver was made later on by S'G' after the take over, who used the old IP numbers. The Squared off ear came after the rounded ear. That explains why you have the later 9-43 barrel. It gets really confusing, just know you have a S'G' made in Grand Rapids, Mi. About 1 hour from me.
Your Sear is correct for your S'G'. Rear Adj sight is H in the shield made by Hemphill, which was likely a field upgrade like the Underwood hammer. Both considered upgrades, could have been done in the field or camp depot. That hammer has less trigger pull than the earlier ones. Your IU magazine is GI issue, made by International Silver for Underwood.

IP 1st serial number started with 1,762,520 but most were made out of order.

Curious if you seen the makers letters under your Hand Guard?

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