Basically, there are three action lengths for Mausers - short, intermediate and long. The Turkish '03 is long, and is a modified Gewehr 98 (WWI German) type. The more common Turkish M38 is the intermediate length, like the Czech VZ24, FN and Spanish. The M48/M48A Yugo and the German Kar98K are the short receiver. Bolts, stocks and other parts won't interchange between the different action lengths. Many earlier 98's also cock on closing (my Turk '03, for instance) while the WWII and later Mausers cock on opening. There are also "small ring" and "large ring" actions to consider. The Turk 38's are large ring actions, but many use the small ring barrels. All Mauser 98's are not created equal. This is why they are such interesting rifles to collect, a lot of variation!