from another website:
" old Sako equipment was purchased by Howa Machinery, the Japanese company that continues to make the Howa rifle, sold under 6 brand names that I can find. Howa, Vanguard, Smith & Wesson, Mossberg, Churchill and RWS. This is why a Howa/Vanguard long action will pretty much drop in to a Sako L61R/AIII stock and vice-versa. The long action Vanguard will also drop into the AV stock but there will be a gap at the rear of the tang as Sako extended the tang on the AV. Bottom metal and barrel contours differ slightly but the footprint of the action is the same. Early Vanguards even had the bolt guide like the Sako. The Howa firing pin assembly is retained in the bolt exactly like the Sako. I once had a Dickson Howa trigger that fit a Sako L579 perfectly."