It's been heavily bubba'd. What should have been a 30" 7x57 barrel has been replaced with a 60 cm 7.9x57 barrel. Stock looks like it's off of a K98. Upper handguard missing. Bolt handle altered. Clip bridge ground off.
Pass it by unless you just want a plinker.
All of the above!!! I would surmise that the pipe wrench marks on barrel chamber come along with no extra charge ... Appears to have been drilled and tapped for a right side mounted receiver aperture sight - stock also notched for that - sight has been removed. Is not "standard" or "military" at all ... But might function and fire perfectly fine. I suspect that I would likely have been happy to drag that one through the bush when I started deer hunting in late 1960's. So, as a shooter / plinker, bore condition is a great part of the value - is still fairly straight forward to acquire most other Mauser 98 milsurp parts. Off hand, I do not know if the magazine box and follower were same interior shape for 7x57 to 8x57JS, or if the feed lips ground in bottom of receiver were the same - so feeding function needs to be verified, if it is to be a "using gun".
Because replacement "scope friendly" bolts for m98 were so common to find to buy, is possible that is a receiver from one rifle, bolt body from another, barrel from a third - raises question about head spacing in that chamber - might all "fit" and be turned to aligning marks - but really needs proper gauges used to verify what you have for head space in there. Could be perfectly fine - Mausers were common at that - but could be very excessive, as well.
It would have been equipped with standard m98 extractor - so was not made to drop a single round into chamber and close the bolt - original extractor not made to "jump over" the cartridge rim - made to load into magazine, and all rounds to go into chamber from magazine. Was / is a "sporter conversion" thing to re-grind leading edge of the extractor to allow for "single feeding" - not clear from your pictures whether that has been done.
Rifle would have originally had a straight handle bolt - the original bolt will have a "B" on the ball - also had the partial receiver serial number along root of bolt handle. When that bolt handle cut off and re-welded to make into scope friendly, requires re-welding very close to rear of bolt's "cocking cam" - one of the hardened places on a Mauser 98 bolt body - so welding without use of heat sink or Heat Stop Paste can soften that cam - leads to galling when bolt operated - won't last very long, in use, if that cam surface has been allowed to go soft. A complete and utter "Bubba" job would have allowed the bolt lugs at front to get hot when welding that bolt handle - soft lugs would make the thing unsafe to even fire, I think.
When trying to make sow's ear into silk purse, Brazil 1908 made in Germany was one of the preferred rifles to start from, in the day when that was a popular thing to try to do at home. I suspect those original rifles likely sold for $25 (or less!) from SIR, Army and Navy, etc. back in the day - so your suggestion of $400 as price is a bit "shocking" to old farts like me - but what do I know - could be a going price - might be someone that really wants one like that.
