It is a standard 50's vintage FN commercial action. The 425 was developed to use in a standard size action and this looks like the WR "White Hunter" economy model rifle from the 50's-early 60's. It is not a Brevex. It will be a bit pricey to keep fed, but as long as it feeds reliably, its a good gun. Just be sure to cycle it rapidly with some dummies, these use a rebated rim cartridge and are a single stack feed. As a DGR, if it dont feed, its worthless, but WR made mods to make it work.