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jjrothWA
11-08-2015, 07:39
Was @ range to sight-in, two M70's, both 22" barrels, first is 30-06 shooting 165gr Sierra SBhp, over 46gr of W748, should be 2650fps but chronograph was responding to low light. Scope height is 1.75 above bore center-line, scope is PENTAX with range gradations. Zeroed @ 100 yds, with POI 1" above POA, then using the second grad, put the POI +5.7".

Will redo the sight-in of the second and hopefully get chrongraph results.

Thanks for reponses.

Sunray
11-09-2015, 09:34
The sight-in won't change the chronograph results in any way. A chronograph only measures the velocity. The rest of it means nothing to a chronograph. The only data you've posted is the velocity too.
Don't have any Win 748 data for .30-06. None listed by Hodgdon either, but there are sites that suggest 46 is about right for roughly 2600 fps with a 168. Allegedly from the 9th Hornady manual.
In any case, sight a 168 in higher than 1" at 100. More like 3 to 4 inches to be on target out to about 300 yards.