Yugo 50s is also well known for FTF in M48s.
Lots of posts on this. The iranian ammo has a hist. of FTF and other issues. It is not desirable for most shooters. OK for pull down.
It is also well kown and tons of posts on the FTF fire problems with certain 8mm ammo in M48s.
The common easy fix is to upgrade the firing pin spring to a 22,24, 26 or even a 30 lb spring. This fixes a lot of the issues.
Available at Wolff springs. Or used to be available.
Your issue spring is 19 lbs on the M48.
Storage conditions on some of the milsurp 8mm and a slightly recessed primer on the fifties Yugo is the cause of a lot of the problems.
All of the ammo you mentioned shooting is only good for plinking, no consistancy except for the Romanian and it is not made for the M48. It is LB ammo. But it shoots well and goes bang and cycles well. Accuarcy is not optimum for 8mm.
Turk ammo has a ton of variables. It is not all the same.
In gen. the Turk out of the forties shoots OK out of carbines, but shoots better out of longer barrelled rifles.
The 1947 Turk is well known for being the stinko year, with loose bullets etc.
Other Turk comes in LB and HB and many diff. years of mfgr. So it is hard to make any absolute statements.
Some Turk is LB around 154 grn. give or take and is VERY fast ammo. Hefty recoil.
In gen. Turk 8mm does not have FTF problems. There are some lots that may have issues.
You will get a wide variety of stories on Turk ammo depending on lot and year, storage cond. etc. Info. I posted is in gen.