There is a Mannlicher forum further down where Gew88's are discussed. There have also been numerous discussion/debates about the ammo for these rifles.
If you can call it a consensus, 8x57JS (turk, romanian, yugo, german, etc milsurp) is not recommended for these rifles, even if they are S stamped. The pressure generated by these loads is considered to be beyond the range for which the 88 was designed.
Modern Rem./Winchester .318 8mm rounds are recommended if you want a commercial cartridge.
This is one of the more recent threads, complete with some comments from the old boards:
BTW, $200 seems a little high to me for a turked 88. However, depending on supply in your area, and condition, it might be an appropriate price. I bought both of my all German 88's (not matching) for about $170 each, to offer some perspective.
What your going to be told is its ok to use fac. 8mm of the rem/winchester USA made type.DO NOT use any surplus type no matter the brand. It is best to reload so the fps stays around the 2k max area. Thats what i do and mine shoot nice. I am not sure about the wolf/other foreign fresh made 8mm.
I have a 88 action re-turked to m38 standards in 1939, looks just like any m38 turk, just smaller and weaker seemingly. Definitely better be careful on high pressure ammo selections, yugo, turk, are real pounders as it is, and what you are to worry with is excessive wear on the action and there are no emergency gas escape holes in the receiver or bolt in case of primer blowout.
Mine was overly accurate at 300 yards with greek surplus, then I got the big idea to sell it off cause I am having all kinds of things coming up and I don't reload yet, and several people had been willing to give me $200+ for what I had on auction with a rare bayonet and rare nice leather sling and bayo frog, unfortunately for someone, that person(auction winner) didn't send me the prescribed post office purchased money order only so I ended up just keeping mine, selling off other things instead.
I heard romanian surplus ammo is low pressure as well like greek, but they say it is best to reload to extreme lightness and I agree.
I like how some "download" their surplus ammo, I was just about to get some reloading gear when I started getting possible job loss news. I heard the best method is to get reloading gear, a special bullet puller in favor of supposedly dangerous kinetic pullers, and download the cases 25%, a sound idea for surplus ammo for these weak actions.
Sometimes I get stressed out and head to the woods with a surplus rifle and some ammo, can't say I won't go there one day with my m88 turk and some greek ammo, knowing I shouldn't. Maybe I can get a better job and more money and get a hell of alot of reloading gear by new years, I got boxer primed cases already.
I have shot my Turked M88 with Romanian 7.92x57 Mauser ammo and had no problems but use my own handloads in these rifles. I would not regularily stress this action with surplus 7.92x57 ammo because all that I've used/seen in a lot of rifles is loaded to it's full capacity - Pretty hot!
I use Buffalo Arms bullets in .318 for one rifle, .321 bullets in another and .323 in the rest and load to moderate velocities ( 2100 - 2200 fps) and anticipate no problems.
Slug your bore before you shoot the rifle. As said - The Rem/Win/Fed 8mm Mauser load is quite mild and should work fine in all these rifles, but I would not shoot it in a .318 bored rifle, prefering a correctly sized bullet.
You will probably find that your rifle's bore is .323 but do not assume until you measure.
My .318 1894 Steyr M88 has a new Czech barrel on it - Shoots great! Turked- M88 shoots awesome as well in .323 bore.