when you have tapered bases what is the proper way of measureing sight hight with tapered bases. i am using the leupold bore sighter, at first i had strait bases on my gun and the leupold bore sighter put me with in a couple of inches of bulls eye then after in stalling my tapered bases i used the same procedure (1/2 out side of objective + hight above bore + 1/2 barrel directly under objective), what i am wondering is if i should use thous numbers and knowing my bases are 20 moa to take the hight above the bore at the center of the scope ? thank you for your input p.s. i wasn't sure were to start this thread so i thought this is were most people look, for the future were should a thread like this go?

Depending on whether it is a long action or a short action it takes about 0.001 inches to give 1 MOA, IIRC. So if you have a 20 MOA base you would have a difference of 0.02inches between the front and rear of the base. In my way of thinking, I am not going to lose any sleep over this trivial of a number Somewhere back in the far crevices of this forum, I have exactly calculated this number as has a guy named ABINOK. A good place to put optics questions is the Optics forum or in the case of this question it could have been the Ballistics part.

yes that is true that over the action it is a small amount but then when you take that same angle and go over the distance of the barrel i have a 26" so lets use that number the difference now becomes .145" and because of the bore siter i am using that is enuf to put me out at 100 yards by 7 " atleast that was my result

Well, that's true. I did not understand the real question you were asking. In general terms, 1.0 MOA is 0.000278 inches per inch so at 26 inches with a 20 MOA base you would have been off by 0.145 inches at the end of the barrel.

yes i seem to have that problem of not being able to put things in to words so that other can compeletly under stand what i am trying to say and i guess i answered my own question while i was at it. thank you for your input, do you think that that little bit might afect how much a ballistic computer will tell you to adjust or in that case is it just a minute amount not to worry about

Depending upon many things such as velocity and BC, but just as a reference point--- 0.1 inch error in scope height gives you a 1 inch error in bullet impact at 1000 yards. If you use real drop data to calibrate your ballistic computation then the error becomes smaller and may be at a different point. In other words, I try to fit my drops more carefully at the longer ranges than the short ranges, so I would tend to make the problem even smaller just by using real data.