M1A Rifle - Variants - Serial Numbers

Serial Numbers

Lee Emerson has made the following M1A Serial Number Comments :

• 000001 to 003700 Texas era receivers tend to exhibit one or more dimensional flaws as identified by retired M14 gunsmith Art Luppino. Springfield Armory, Inc. in Texas assembled about 2000 complete rifles using USGI parts before it was sold to Bob Reese (Geneseo, IL). An additional 120 rifles were built for Elmer Ballance by Glenn Nelson and Wayne Young before June 1974 using stripped or barreled receivers supplied by Elmer.

• 000001 to 063XXX Receivers machined by Valley Ordnance Co. were given a lot of hand grinding and polishing by Melvin Smith. Specifically, these areas were: 1) the exterior heel corners on the sides 2) the flat surface aft of the operating rod channel 3) the top surface of the left receiver wall from the cartridge clip guide to the barrel ring 4) the vertical surface on the right side behind the cartridge clip guide all the way back including the windage knob ear 5) the left side of the barrel ring forward of the horizontal scope mount groove 6) the magazine well aft of the feed lips and 7) the top surface of the barrel ring after all machining operations that located off the barrel ring had been done. This cosmetic detailing is evident as late as M1A serial number 062857 but was no longer being done by serial number 064922. Note that the hand polishing served to enhance the aesthetic appearance but did not add to the functional ability of the M1A receiver. As Melvin Smith moved to semi-retirement the receiver surfaces noted above were finished by machine. For example, the magazine well on M1A receivers was cut and broached by machine tool after Mr. Smith purchased Hillside Manufacturing.

• 000011 Receiver left side connector lock hole is present.

• 000049 Receiver left side connector lock hole is missing. Receiver heel rear end wall centerline thickness is ¼ “.

• 000377 Highest observed serial number with 7.62-MM marking on the receiver heel.

• 000440 Lowest observed serial number with 7.62-mm marking on the receiver heel.

• 000567 to 000708 Within this serial number range, Valley Ordnance Co. changed the receiver design. The rear end of the M1A receiver bolt right lug slot, located under the rear sight base cover, was extended 0.080 " to the rear to prevent possible damage to the bolt roller.

• 001XXX to 002XXX Gray-Syracuse, Inc. becomes the casting supplier of M1A receivers.

• 002010 Receiver left side connector lock hole is still missing.

• 002068 Receiver left side connector lock hole reappears for good.

• 002709 Lowest known serial number (stripped receiver) sold by SA, Inc. located in Geneseo, IL.

• 002877 Highest documented serial number (complete rifle) shipped from Springfield Armory, Inc. in Texas.

• 002884 Receiver heel rear end wall centerline thickness is 5/16 “. Serial numbers after this have noticeably less steel cut away in the bolt raceways after of the cartridge clip guide.

• 002884 to 010048 At some point in this serial number range, the receiver design was changed to incorporate a hemispherical cut in the windage knob ear outboard side (commercial NM rear sight).

• 002903 Lowest documented serial number (complete rifle) shipped from Springfield Armory, Inc. in Illinois.

• 003306 Highest documented serial number (stripped receiver) shipped from Springfield Armory, Inc. in Texas.

• 003700 Highest documented serial number for receiver production while Springfield Armory, Inc. was located in Texas. Valley Ordnance Co. resumed receiver production on September 21, 1974 at serial number 003701. Springfield Armory, Inc. in Texas was sold around November 01, 1974 to Bob Reese in Illinois. During July and August 1974, Valley Ordnance was completing 75 receivers per week. Based on this output, the highest receiver serial number while Springfield Armory, Inc. was located in Texas is estimated at about 004075.

• 004357 to 004379 January 01, 1976: In this serial number range, a factory one year limited warranty is in force after the initial purchase of a rifle.

• 007XXX to 020XXX SOME receivers made from AISI 4140 alloy steel. The elevation serrations wear prematurely but can be repaired using an elevation disk. These receivers are serviceable, no other issues reported.

• 007XXX to 037XXX Springfield Armory, Inc. does not have USGI chromium plated barrels for assembly of complete rifles. Factory installed barrels in this serial number range will be commercial manufacture but machined by Hillside Manufacturing (Dallas, PA) using Wilson Arms blanks.

• 007041 A commercial unlined standard profile barrel and a commercial operating rod used to build standard model M1A.

• 0093XX A commercial unlined standard profile barrel, a commercial bolt and a commercial operating rod are used in the assembly of this standard model M1A. Hillside Manufacturing machined reproduction operating rods, trigger housings, flash suppressors, bolts, operating rod spring guides and barrels. No gas cylinders were made by Hillside Manufacturing or Valley Ordnance. It has not been confirmed but most likely the trigger housing and flash suppressor castings for M1A parts were also produced by Gray-Syracuse, Inc. since Mr. Smith was loyal to his suppliers. Valley Ordnance did the finish machining on cast semi-finished cartridge clip guides supplied to the firm. The reproduction bolts, operating rods and trigger housings were stamped at Valley Ordnance. The operating rod spring guides were made from plate steel using a punch press with progressive dies. The operating rods were supplied to Hillside Manufacturing already welded together. Hillside Manufacturing machined the operating rods to final dimension.

• 017XXX to 020XXX The 18 “ barreled M1A models first appear.

• 030061 Receiver heel rear end wall centerline thickness is 3/8 “.

• 0343XX Highest observed serial number with receiver bottom side right hand ridge.

• 038XXX About this time, large quantities of USGI M14 parts are imported into the United States and become available on the surplus market. Springfield Armory, Inc. and other firearms related businesses buy large quantities of these USGI parts.

• 038770 Highest observed factory built select fire model

• 040XXX Receiver was redesigned to move the barrel chamber slightly forward to increase bolt lock up time.

• 042201 Lowest observed serial number without the receiver bottom side right hand ridge. The bottom side ridge was removed from the design as part of the changes made for economic reasons. It meant two less machining cuts but it also had the benefit of a better fit with various makes of stocks.

• 042201 to 063000 This is the serial number range that I refer to as the Golden Age of the M1A. The receiver design had fully matured by this time. The receivers were hand finished by the original designer and master craftsman, Melvin Smith. Springfield Armory, Inc. was awash in USGI parts during this period. Thus, factory built standard model M1A rifles in this serial number range were built with a very high USGI parts count.

• 0630XX 7.62mm caliber marking is on the receiver heel.

• 063112 7.62mm caliber marking no longer appears on the receiver heel.

• 064872 Rear lugged receivers are now available from the factory.

• 070005 to 072074 January 01, 1993: In this serial number range, a lifetime limited warranty is now in effect for the original buyer of a factory built rifle.

• 07157X to 075XXX Factory shipping boxes change from green and white to blue and white.

• 072XXX to 073XXX By this serial number range, the operating rod rail dimensions have been narrowed for a tighter fit with the operating rod tab.

• 0748XX Late version SA, Inc. commercial manufacture operating rod now used to assemble complete rifles.

• 081004 Built at the factory with the following USGI parts: TRW trigger housing, HR-N hammer, TRW bolt, Winchester barrel, and WCE USGI rear sight elevation and windage knobs.

• 084000 Generally accepted highest “safe” serial number for pre-’94 AW ban rifles. Since about this serial number, no M1A rifles have been factory built with lugged flash suppressors.

• 097726 The last completed receiver from Valley Ordnance Co. is shipped to Geneseo, IL.

• 098XXX The loaded standard model is debuted.

• 100042 Highest observed serial number with Gray-Syracuse, Inc. pour lot marking

• 102570 Change in pour lot markings indicates the change in casting supplier for receivers.

• 124XXX The factory is installing commercial manufacture forged bolts (F prefix series) in rifles.

• 136XXX to 165XXX Some receivers in this range have scope mount grooves too narrow for side three point scope mounts offered by other companies, e.g., Sadlak Industries, Smith Enterprise, etc.

• 139XXX Use of USGI parts in factory built rifles begins to noticeably drop.

• 161920 With rare exception after this serial number, commercial unlined barrels are installed on standard model M1A rifles. SA, Inc. machines the barrels from Wilson Arms supplied blanks.

• 162708 Lowest observed serial number for the M1A SOCOM series.

• 165XXX About 300 receivers in this serial number range have heels stamped AROMRY instead of ARMORY.

• 166761 Highest known serial number for a complete rifle built during the ten year federal Assault Weapons ban.

• 192260 Factory built standard model with all commercial parts except USGI fiberglass (with black crinkle) stock, operating rod spring guide, trigger housing and hammer.

• 218XXX About this serial number, M1A rifles may be assembled with new manufacture polymer stocks as the inventory of USGI fiberglass stocks (with black crinkle) have been used up.

• 241552 Most recent manufacture date (November 2009). By January 2010, 22" standard profile barrels, muzzle brakes and lugless flash suppressors are manufactured by Dasan Machineries, Ltd. (Jeollabuk, Korea).