Item     Nr.:        1060
Brand   :             SIG (Schweizerische Industrie Gessellschaft)
Model      :          SG 510-7 T
Caliber:              7,62 NATO

The SIG 510 in its various commercial and “sporting” variants, derived by the original design of the Swiss Stgw 57 cal 7.5×55 Swiss
The 510 series includes:
- 510-0 is the technical name of the SIG Stgw 57 cal 7.5 Swiss
- 510-1 Same as the StGw57 but Cal.7.62  NATO
- 510-2 Lightened variant with wooden handguard Cal.7.62  NATO
- 510-3 Definitive shape Cal. 7.62 x39 (with shorter barrel and curved magazine)
- 510-4 Definitive shape Cal. 7.62 NATO replacing both the 510-1 and the 510-2

From the latter borns the sporting versions we care about. In the early 1968 the weapons derived from SG 510-4 for sports use, further  modified, receives the official designation of  SIG 510-7T and an accompanying letter that the SIG wrote on 22 8 1968 to the Italian importer (the Brio Company of Turin) they clarifies that this variant SIG 510 7T is created specifically for the sport-shooting and for hunting (for these model were imported in Italy, about a dozen).  The rifle shown here is one of them.

Note the first type of  straight grip and three position selector switch

In the second Deutsche Waffen Bags, held in May 1969 in Schwabisch Hall is finally presented the current version of the sport-model known as  SIG AMT (American Match Target) for the cal. .308 NATO (and even these were imported + / - the same number). One of them is Item Nr.: 1061  SIG-AMT

These events occur in the same period in America, please see the site where American BIGGERHAMMER (http://www.biggerhammer.net/sigamt/sar/) tells you more or less the same story:
In 1969 several SIG 510-4’s, perhaps less than a dozen, were imported into the US. These were legally parallel to the FN “G” series rifle in that they were built around full automatic receivers with semi automatic internals. However, BATF approved these rifles as semi-automatics and therefore not falling under the restrictions of the NFA.
Later in 1969 SIG responded to emerging gun regulations in other countries (notably England and Italy) by slightly modifying the 5 10-4 to make it more “sporting”. This included deleting the bayonet mount and rifle grenade rings on the barrel. When imported into the United States this now became the SIG AMT. (American Match Target).

As well explained in the same site AMT’s were imported during the period 1969-1978. From 1979-1989 more AMT’s were imported although they were reportedly made up of parts which had been manufactured earlier. The weapons in question are clearly visible from the photos and are from the excellent + + to mint /new in box conditions for Articolo Nr.:   1062 - SG510-4  -AMT

Note the upper hand-guard not present in  SIG-AMT and  SG510-4 AMT