OK, so my 1911 barrel has the H and P on top and a 5 underneath. According to the pics from this site USGI M1911 and 1911 A1 Barrels they mean WWI military contract.

The thing that throws me is that there is also a partial G beside the 5 underneath. According to the site the G means WWII. What does the G stamp mean? Was it used again during WWII? My knowledge on 1911's is zilch, so any help is appreciated.
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