BSA Sweet 223

Before it starts, i know, " you get what you pay for"....but, as i was wanting to spend $100.00 and not 5-6 hundred.....i bought the BSA Sweet 223 6-18 scope...took it to the range today to sight in, on a 20" RRA ar-15...all went well till i went to 2 hundred yards , set the dial at 200 and was 4" high....didn't check target right then, redialed down to 100 and to my real surprise, it returned to perfect 100 yd zero!!!!! But my question: the 200 yard mark for 55grain .223 bullets is approx 12 clicks up from 100 yds......reloads , nosler 55 gr ball tip at approx 3100 fps....all the data i find shows maybe at the most a 3.1 " difference between 1 & 2 hundred yards in elevation difference......with a 1/4" click at a hundred, at 2 hundred that goes to 1/2" click, correct? At approx 12 clicks up, that makes it 6" height adjustment..........Am i shooting the wrong B.C. bullet for the dial, or am i missing something here???? Iv'e read reviews where other guys are hitting right on with the dial marks! Any help would be great, as i am questioning my sanity, or lack of.....Thanks, rsbhunter

I have one and it worked fair.  NOT exact but within an 1"  FPS seem a little fast but I dont' know what the mil spec 55gr fps should be.

 There are just too many factors that fall into play with the ballistic turrets to go buy the markings. Just think about how many different types of 55gr ammo is available,all shoot at different fps,and are loaded with different powders,etc.