Every scope has some adjustment moving it forward or backwards for mounting it on the rifle but the eye relief will not change. It has all to do with how you hold the rifle for shooting. When you lift the rifle and get ready to shoot , the scope has to be within the limits of how you place your head in relation to the stock. The scope has to be place so that’s it’s comfortable to shoot. This was done a long time ago when you first got the scope. If you’re not sure or don’t feel comfortable setting the scope they will help you at your sporting good store after buying the scope. Good luck....