How old is my Merrill Carbine, Type I S/N 5681? Are there any records of the soldier to whom this carbine was issued or to what regiment it was assigned?

Early 1960s
MODEL 742 WOODSMASTER Description: Autoloading, gas operated improvement of Model 740, 4-shot detachable magazine
Introduction Year: 1960
Year Discontinued: 1980
Total Production: Approximately: 1,433,269
Designer/Inventor: Research & Development
Action Type: Semi-automatic gas operated
Caliber/Gauge: .243 Win, 6mm Remington, .280 Remington, .30-06, .308 Win
Serial Number Blocks:
1951-1967 1,000-541,000
1968-1975 6,900,000-7,499,999
1975-1978 A6,900,000-A7,499,999
1978-1981 B6,900,000-B7,499,999
Grades Offered:
742A Standard
742ADL Deluxe
742BDL Deluxe
742CDL Deluxe Carbine
742C Carbine
Variations:
150th Year Anniversary
Canadian Centennial (1967)
Bicentennial 200th United States Anniversary (1976)

https://www.gunvaluesboard.com/remington-barrel-date-codes-date-of-manufacture-2164.html

https://www.remington.com/firearm-history/model-742-woodsmaster

https://www.google.com/search?q=742+Remington+308+Serial

..

https://www.gunsinternational.com/guns-for-sale-online/rifles/springfield-rifles-trapdoor/u-s-springfield-model-1886-experimental-trapdoor-carbine.cfm?gun_id=101079098

Serial number 340182

https://www.gunsinternational.com/guns-for-sale-online/rifles/springfield-rifles-trapdoor/springfield-rifles-trapdoor.c1409_p1_o6.cfm



https://www.gunbroker.com/All/search?Keywords=springfield%2045-70

https://en.wikipedia.org/wiki/Springfield_model_1873

https://www.uberti-usa.com/springfield-trapdoor-cartridge-rifle-and-carbine

https://www.americanrifleman.org/articles/2011/1/25/us-springfield-45-70-gov-t-trapdoor-carbine/

https://www.thefirearmsforum.com/threads/winchester-m1-carbine-value.146923


Check with a collector's web site instead of FIXYA aimed a do it yourself repairs.

not sure if this will help you out.. http://www.history-sites.com/cgi-bin/bbs62x/cwaemb/webbbs_config.pl?md=read;id=4575 ..or this one... Spencer model 60 carbine serial no 27089 Google Search

cant find any charted load data online for it
interesting question
interesting weapon history

M1 carbine Wikipedia
Lee Loader30 M1 Carbine With Rare Aluminum Powder Measure Vintage

I take help from online websites that have this service like helping in repair some like reliable-store have instant help.. others are a bit slow which I don't prefer... rest is up to u
..
U can also get free manuals

The rifle was originally designed by Jonathan Browning, brother of John Browning, but died before the design was completed.
Winchester hired David "Carbine" Williams, who had began design on a "short-stroke" gas piston design, having him finish the M1 design.

If you are unsure of what to do, I would suggest you take your carbine to a gunsmith. Safety is an important thing to have installed right!

Seems these guns are kind of a convoluted mess with the way they were produced in two different factories with overlapping serial numbers, and factory markings. Here's a link to a good forum on the guns and the process by which they were marked

http://m1family.com/topic23.html