New guy from North Carolina

@Smokepole, look at the receiver details!

@stjohnmc, look at the name under the rear sight on the right side. It is marked SAGINAW SG or SAGINAW S'G'

I suspect you will see the G and the apostrophe.

Saginaw Steering Gear Div of General Motors produced carbines at Saginaw Michigan and used SG or S.G.

There Grand Rapids Michigan location they used the S'G' on the receiver and parts made there.

Smokepole is correctly stating that the serial number is in the block assigned to Saginaw Michigan location, however there are Grand Rapids receivers with those numbers in a span of serial numbers.

They were filling one contract at two locations and delivered carbines are delivered carbines.

This is why there is a link in my signature to a request for Steering Gear carbines so we can find the serial span, groups of numbers used on one receiver or the other, possibility of duplicate serial numbers as well as an outside chance of an incomplete, but obvious receiver that was finished at the other location.

So front ring details and what it says that is obscured by the rear sight are key to this research

Re: Stock markings.

Only the SG carbines have additional marks in the slingwell.

The stocks for I-P/S'G' carbines produced at Grand Rapids only have the stock maker's stamp.

Here's the slingwell of a Robert Irwin stock for Saginaw Gear.

However the S'G' Ordnance acceptance stamps show that the stock was originally on a carbine produced at Grand Rapids.

This caused me some confusion when I first got it.  See http://www.uscarbinecal30.com/forum/saginaw-owner-in-se-pa_topic5028.html

O I is probably an Overton handguard for Inland.

That means the stock that is now on that rifle was not the original stock put on at the factory by Saginaw. Once the M2 (selective fire/automatic version of the M1) came out, they stopped manufacturing the early M1 stock and only made M2 stocks. The M2 stocks are beefier (I.e. the pot belly) with thicker wood in some places, have a longer barrel channel, and a cut out slot on the interior left side against the receiver to accommodate the M2 selector switch. Many M1 carbines received new or upgraded M2 stocks during the post-WWII rebuild period, where they also received the barrel band with the bayonet lug as well as the adjustable rear sight. Some M1’s may have retained their original WWII stocks for many years after the war and the M2 stocks could have been added anytime during the Korea or Vietnam era.  After WWII, if a stock needed to be replaced, the depot level and armory folks had M2 style stocks to replace them with.