Moved from the tech manual thread. Alrighty then, I'll answer some of your questions here, as well as throw in some miscellaneous comments. 1) There is no such thing (and never was) as 7.92 8mm NATO. NATOs first standardized cartridge was the 7.62X51. Prior to that, there was no standard NATO round, each member nation fielded what they had or felt like. The 7.62 NATO was derived from the commercial .308 Winchester, and was made standard in the early 50s, IIRC. Of course, you know that the standard now is 5.56X45. 2) You referred to 8mm 187(?) gr rounds, undoubtedly milsurp. Not a long range round, but of better than military standards today which are around (again, IIRC) 2 MOA in standard issue arms. Select arms and ammo can do better, and often do. The milsurp you have is not select, and can't be expected to perform any better in your rifle. 3) We can't tell from here what your customized rifle might be able to do, since we don't (yet) know what mods your smith did for you. Don't expect anything better than miltary accuracy at best. 4) If you are using milsurp, then cleaning out the salts as soon as you are done for the day is important to preserve the steel as you know. Yes, hot water will do the job, but Hoppe's (and other bore cleaners) is better in that it also coats the steel against corrosion from water that you don't get out with heat. IMO, and that's what I do with my MNs. No more corrosion than when I got them, and I've pushed a number of Berdan primed milsurp thru them. Don't use a stainless brush unless the barrel is pitted. IMO, fiber is best, bronze OK, neither will wear the steel barrel. 5) In the chatbox, you asked if anyone heard of muzzle wear from steel cleaning rods. Yes, very common in old military barrels that could not be (or were not) cleaned from the breech. There are two "fixes" in common use, first, cut off the damaged rifling from the muzzle and recrown it, the second is to backbore the muzzle past the damaged section of rifling. Arguably, the most important item for accuracy is a concentric muzzle with no burrs. (Competitive shooters treat their muzzles better than they treat their SOs.) 6) Reloading your 8mm casings is a chore best left to experienced reloaders that have the necessary equipment to deprime and machine the primer pocket for Boxer primers. Or you can figure out how to get the expended primer out (hydraulic deprimers are the only way I've heard of to get that done) and reprime with Berdan primers if you can find them. Pretty scarce. 7) One of our other comms indicated you used some hot handloads in the past that made the bolt sticky. I think I commented on that already (there was some rum around here last night), but again, a sticky bolt is an early sign of overpressure loads. If those were in this rifle you are talking about, I hope you told your smith about it so he could check for damage to the piece when he did the mods. Mauser actions are pretty tough, but not indestructible. Look for cracks at the base of the bolt lugs and receiver ring, might want to do a dye pen test that will show cracks that can't be eyeballed. And, of course, check the expended rounds for cratered or partially pushed out primers in those rounds that stuck the bolt. 8) You indicate an interest in "long range" shooting. Somehow, I get the idea (forgive the presumption) you are fairly new to the game. I have to repeat my doubts about your groups at 400(?) yards, the roughly 2 inch 2 shot groups are (I'll state categorically) impossible; that's about 1/2 MOA which is not credible from a milsurp barrel, even off a machine rest. (And the paint bucket at 3/4 of a mile is pure bunkum discounting a large helping of luck.) All that said, you are in a pretty good position to start the game. Your Mauser is a sound platform if your smith did a decent job. It's time to practice, starting at reasonable distances to tune your skills and figure out what you need to reduce group sizes. You first, gun second, ammo third, mix well with time and money, and you should be able to get 1 MOA with irons and better with a scope (probably not with a milsurp barrel.) Here starts the arguments over hardware, but I'll start off with saying 400 yards is pushing and wishing for better than 2MOA at "long" range off a bench with your current rifle. For me, and maybe me only, "long" starts at 150 yards regardless of gun. (I blame my eyes, there's always a "reason."). There are folks on the site that think "long" is over 400, but they have miles off their back porch.