The Rifle
The receiver is stamped with U.S. and the serial number is 1048. This is an all numbers matching gun, with 1048 stamped on the top of the upper next to the cheek piece, 1048 is stamped on the barrel and 1048 is hand engraved on the bolt.
There's another number stamped on the bolt, it's 089 and since it doesn't match any of the serial numbers, it most likely represents this rifle being number 89 of the 100 built for the Corps. I checked my other USMC Barrett and it is stamped with 017, which is also different than the rifle's serial number. This means that the bolt is correctly marked and is serial number matched to the receiver. The bolt also has 2/91 stamped on it, which means that the bolt was produced in February 1991. I tried to get a pic of the serial number on the bolt, but it's difficult to see in the photo because it's a shallow engraving, it's to the left of the date.
The barrel is stamped with the rifle's serial number, SLAP and 3/91. SLAP stands for Saboted Light Armor Penetrator, which is the type of .50 caliber ammunition issued with this specific rifle (other .50 cal ammo can also be used). 3/91 means that the barrel was produced in March 1991.
The original grip was a standard A2 grip, but at some point it was swapped out for a Hogue grip. This was probably replaced by the a sniper who used the rifle, but an A2 grip is an easy 30 second swap if you want to go that route. The receiver has 2 welded bases with a single picatinny rail across them. The rifle originally had 1 welded base that utilized a special Unertl mount. The USMC sent all their M82A1 rifles back to Barrett in the mid 1990's to have the second base and picatinny rail added.
The word "Adios!" was also written in marker on the left side of the receiver long ago, this is obviously a message from the sniper to whoever is on the receiving end of his wrath! The marker is very worn and is barely noticeable (I tried to take a picture of it).
Another USMC Barrett M82A1 came up for sale by Rock Island Auctions on December 7, 2019 (just a few weeks ago) and sold for $43,125! I'm selling this rifle for less than that price and this rifle has a prototype scope that isn't available anywhere else! You can always get a Unertl MST-150 from the CMP, but this is the only time you'll ever find a USMC prototype USO SN3 SSDS! Here's a link to the recent Rock Island Auction:
The Scope
This is a US Optics SN3 SSDS (Scout Sniper Day Scope) that was made in 2005 and submitted to the Marine Corps for testing during their search for a new sniper scope. USO lost to Schmidt & Bender, who's scopes were first issued in 2006 and are still in use. Only 3 of these prototype .50 cal USO SSDS scopes were made and only 2 are still in existence, this is one of those scopes. During testing the Marines wrote "05G05" in silver marker on the top of the scope.
The scope is 3.5-15x, has a mildot reticle and ther rings are Badger Ordnance. The EREK knob is a single revolution ballistic elevation turret with markings from 300 to 1,800 yards. The Barrett M82A1's were originally issued with a Unertl MST-150 .50 cal scope, which the Civilian Marksmanship Program (CMP) currently has available during their weekly auctions. This give you the opportunity to use either the 1 of 2 known USO prototype scopes or procuring an original USMC Unertl from the CMP. The original paperwork from USO about this scope is included, the last two photos show this original documentation.
Full Auto Applications
