Hi guys. Picked up a very well-used, sporterized K-98 in an estate sale.
An aftermarket turned-down handle has replaced the original, it's got a Timney trigger, the magazine plate has been modified so the bolt will close without having to depress the magazine "sled," a Buehler safety was added, it's also got Lyman peeps and a hooded ramp front. Stock is an early fiberglass model. It has an old side-mount Weaver or Williams scope mount - I forget which, and an old Weaver 3X scope. IMO, the rifle looks like it was built in the 50s or 60s. All work was professionally done - and done very well. The rifle has been hunted hard and it shows.
It has the original, stepped barrel, but it has been re-bored to .338. I had a chamber cast made - and it's a standard 8 x 57 necked up to .338. Can't find any info on it save that it's been called "8 x 57 O'Connor" and this article:
Thinking I'd like to shoot this and see how it performs, as the bore looks very good. Of course, I can't find any dies, but will be sending off the chamber cast to RCBS to see what they might have.
Wondering if anyone might know anything else about this caliber and this conversion.
Welcome aboard. Your first question is not an entry level one, to be sure.
That is not a conversion I have seen before. It was far more common to take an 8mm bored 98 and rechamber to 8mm-06 than it was to stay with the x57mm case and go to a different bore.
You could extrapolate loading data by comparing 7x57 data with .280 Remington data, and then replacing 338-06 for the .280. (If the 7x57 takes 3 grains less powder than the .280 for a given powder and bullet, then your .338x57 should take about 3 grains less of that powder than the 338-06.) But the standard admonition to start low would apply. Given the expansion ratio in that case, I think the medium fast powders would be the place to start. R15, Varget, H4895, and IMR 4064 would be prospects. As a guess, without any loading books in front of me, I think you would be getting a 200 gr bullet going about 2500 fps. You might find that rechambering this gun to 338-06 would be a practical strategy. It has no particular value as it is, and there would be cheaper dies and more loading data for the 338-06, and resale might be higher as well.
You have a really cool wildcat from a historical perspective. You should be able to use 8x57 starting load data with any given bullet weight and you may be able to work up to max published loads for the 338 Federal. This pretty much works in the 7x57 where a guy can substitute 7mm-08 data in modern stong actions like good 98 mausers.
Have your rifle checked out by a good smith who is familar with mausers for safety,and use starting loads for 180 and 200 grain bullets for the 8x57 and you should be on good,safe ground. I would prolly not excede max published loads for the 338 Federal which operates at 60,000psi but has smaller case volume than your 338x57 case.
Thanks guys. I may go the .338-06 route, or rebarrel it. Trying to have some fun with an interesting project and keep it cost efficient. Figure I'll price dies for it as-is and weigh that cost against the cost of a new barrel and install. I know it's still a gamble as to whether it will shoot well or not, so I'll scratch my head and go from there.
I'd like to mimnimize the cost for things such as lengthening the magazine, opening the bolt face, etc., so not sure what I'll eventually do. Figure if I rebarrel, maybe .338-something, or 6.5-something.
Still interested in what anyone might know about this old shooter.
If it shoots, you might try CH4D for dies. Some don't like his dies but I've had good luck and the loaded rounds have been excellent when checked for runout. They have a 338-8mm listed for $78.25 which is a heck of a lot less than other die makers. Of course, if you call and Dave Davison answers, be prepared to have a big phone bill or use your cell phone with free long distance and plenty of minutes. That man will give you more informatiion than you dreamed possible. Ward
Thank you SOOOOO MUCH!! I'd never heard of that company, but checked their site and I'll be giving them a call. I have a sneaking suspicion that this old rifle just might shoot. I'll post up how she goes.
I have a 9x57 Mauser (.358x57), and developed loads for it by interpolating from 8x57 data, along with some 9x57 info I rounded up. If you're careful and pay attention, building loads for such a rifle can be great fun.
How about some pictures?
Dennis
"The more you run over a dead cat, the flatter it gets."
"If you're asking me something technical, you may be looking for My Other Brother Darrell."
"It ain't foot-pounds that kills stuff -- it's broken body parts."
If you decide to rebarrel it, you may find someone on this list who would be interested in buying the original barrel. If, that is, you didn't want to keep it.
I'll see if I can figure out how to post pix and put some up in a few days - I'm away from home at the moment. If I decide to sell the barrel, I'll post up here.
Re CH4D, spoke with Dave and had a nice conversation. Said the last set of .338 x 57 dies he made was for someone back in 1990. Wonder if it was for the owner of the rifle I have?
Anyway, Dave says he's got a alot of business and it'll be a year before he gets to it. So... thinking I'll re-stock and tinker with cosmetics while I'm waiting. Maybe load up on some .338 projectiles and more 8mm brass as well.
.
