I was rummaging around in a safe of mine and found this.

Hanyang 88

It is an 1888 Commission Rifle, a.k.a. "Gewehr 1888".  They were made in Germany and served a relatively short life before being replaced by the 1898 Mauser.  A lot of them were surplussed to Turkey and some made their way to China.

https://en.wikipedia.org/wiki/Gewehr_1888

Edit to add -  previous reply is probably correct, it is probably one of the unlicensed knock-offs.

It does have rifling! Is this thing safe to shoot with modern ammo?

Probably not, at least I wouldn't.

I've got a Gewehr 1888 in much better condition, and I load special reduced power loads for it using .318" bullets.

I don't know about the Chinese clones, but the original rifles used a smaller .318" bore instead of .323" like most modern 8x57 Mauser rifles.  Now some of them were re-bored to .323, but unless you slug it to measure I wouldn't risk it.  And I wouldn't shoot full power modern commercial 8x57 Mauser (leet alone some of the hot milsurp) in an 1888 in general.  I'd be suspicious that the Chinese clones may not be as good metalurgically as a German made rifle, and that one looks pretty well worn.  Better safe than sorry.

FWIW, my loading uses a powder charge similiar to .30-30 Win using IMR 3031.  It is just enough to give a good mouth seal (avoid sooting).  It is very pleasant to shoot and decently accurate.  You can get the .318" bullets from Buffalo Arms if I remember right.  If you want to load them I can look up my notes on the load data.

As far as I remember the Chinese never really made the switch from .318 bore especially on the Hanyang 88s.  This should be chambered for the original round nose 8mm loading

I would get a gunsmith to check it out, have the chamber cast and bore slugged to determine caliber and bore specs, and then shoot cast bullets and mild loads.

Sound advice in my opinion.

If it were a German 1888 I wouldn't have any problem shooting it.  They are made from good quality steel. I load my own for it.   I shoot a 150 grain bullet around 2300 fps.  It is in the 30-30 range

I am not sure I would shoot one of them. Unknown quality of the steel.

I would consider it to be a "Wall Yanger"

Im sure if the steel had any quality issues then they would have surfaced sometime in the 80-90 years since the rifle was made or in the world war and civil war it fought in.