While I cannot add much about the screw in question, I can say with authority that the long slide 48 on a vintage 03 sporter will reach 1153 yd with a fairly standard load using a 220 gr cast bullet. It was quite fun, and not very difficult to hit the Whittington white buffalo, once we spotted a ranging shot. It did take about 20+ rounds to accomplish that, however, as I had no ballistic data to attempt it with before hand.

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BrentD, (Professor - just for Stan)
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