Just came across a bit of info That could trip you up for underwood carbines purchase. I have come across this before and did not do the purchase do to not knowing. The receiver and barrel dates being way off by several months either way during assembly. Found this info in U.S. M1 CARBINES,WARTIME PRODUCTION by Craig Riesch. According to the book second s/n block came out after the third s/n block. The second s/n block 2.3 milliom thru 2.9 million was produced november 1943 - march 1944. Underwood assigned this block to 4 or 5 different contractors.Underwood took possession from all contractors at once in late 1943 .The parts received first was used first,so receivers were not necessarily assembled in consecutive serial number ranges. Ending up with a good spread between receiver and barrel dates either way.Feed back would be great, Any ones input would be valued here.Thanks hiker12
Underwood had assigned the second block of serial numbers to four sub-contractors. When the first block was finished they started the third block but stopped in late September 1943 as the sub-contractor receivers started coming in. They used these till the beginning of 1944,then finished the third block of serial numbers, back to some of the second block and then finished with the forth block of numbers. They still were getting in sub-contractor receivers when the contract ended. What they had on hand from sub-contractors and from their own receiver production they sold to Winchester about May 1944. Winchester went to at least one if not two of the sub-contractors and bought more receivers from them. Some of these were finished and some were not but it helped Winchesters production out.