who produced the modern bolt-action sniper rifle  which Steyr SSG 04 was the basis of
Steyr SSG 04 The Steyr SSG 04 (German: Scharfschützengewehr 2004, English: Sniper Rifle 04) is a modern bolt action sniper rifle developed and produced by Steyr Mannlicher in Austria, as a complement to Steyr's SSG 69, using the same Safe Bolt System (SBS) action developed for Steyr's hunting rifles. It is also the basis for the Steyr SSG 08 and Steyr SSG Carbon.
.338-06 The .338-06 is a wildcat cartridge based on the .30-06. It allows heavier .338 caliber bullets to be used from the .30-06 non-belted case. This is a better choice for heavy bodied game such as moose, elk, and brown bear than the .30-06. 338 caliber bullets became more widely available after the introduction in the late 1950s of the .338 Winchester Magnum cartridge, frequently chambered in the Winchester Model 70 rifle. The .338-06 maintains much of the benefits of the .338 Magnum cartridge but has substantially less recoil, makes more efficient use of powder, and allows use of widely available .30-06 commercial and military cases. It is similar in concept to the .333 OKH as well as the .35 Whelen, which also use the .30-06 brass case as a basis for the cartridge. Thanks to the large number of rifles based on the .30-06 family of cartridges, having a .338-06 made usually only requires a simple barrel change by a competent gun smith. A-Square adopted the caliber as the .338-06 A-Square in approximately 1998, and was approved by SAAMI as a standardized caliber. Weatherby offered factory rifles and ammunition, but has now dropped the rifles from its inventory. The 338-06 A-Square tends to have a velocity advantage over the .35 Whelen and uses bullets that retain velocity and resist wind drift better than similar weight bullets fired from the .35 Whelen.