Guest Posted July 8, 2018 Report Share Posted July 8, 2018 “Heat has the exact opposite effect, with the same rule of thumb: 0.5 to 1.0 m.o.a. for every 20 degrees warmer than your sight-in temperature. Just remember that rules of thumb are simply guidelines; I’ve never found any consistency with climatic influences on ballistics. However, it is absolutely true that when ambient temperature increases propellant powder gets “hotter” and produces more velocity, which should raise your point of impact.”Read more: http://www.rifleshootermag.com/ballistics/environmental-factors-shooting/#ixzz5KeVZlEJF Really? Had me thinking because my zero moved by a mildot this week end (temp at 30’C). Quote Link to comment Share on other sites More sharing options...
Dougy Posted July 8, 2018 Report Share Posted July 8, 2018 (edited) See what happens when you develope a load close to max during the colder months, then check your pressure signs shooting in the 30s. And I would like to know how old the chap is, 100 years ago he was shooting in some pretty poor conditions. Edited July 8, 2018 by Dougy Quote Link to comment Share on other sites More sharing options...
PPP Posted July 8, 2018 Report Share Posted July 8, 2018 4 clicks difference on Hawke HMR scope at 100 yards between 0 degrees last time zeroed and 26 degrees last Weds evening, also moved 2 clicks right.. Quote Link to comment Share on other sites More sharing options...
Guest Posted July 8, 2018 Report Share Posted July 8, 2018 Then again, maybe I just knocked the scope at some point.... Quote Link to comment Share on other sites More sharing options...
Dekers Posted July 8, 2018 Report Share Posted July 8, 2018 Zero need checking and adjusting as required regularly, but that's down to a lot more than just temperature/atmospherics! Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.