Forums
New posts
Search forums
What's new
Articles
Latest reviews
Author list
Classifieds
Log in
Register
What's new
Search
Search
Search titles and first posts only
Search titles only
By:
New posts
Search forums
Menu
Log in
Register
Install the app
Install
Forums
Rifles, Reloading, Optics, Equipment
Rifles, Bullets, Barrels & Ballistics
Problem with accurate readings from ballistics progs.
JavaScript is disabled. For a better experience, please enable JavaScript in your browser before proceeding.
You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an
alternative browser
.
Reply to thread
Message
<blockquote data-quote="jwp475" data-source="post: 244672" data-attributes="member: 3776"><p>IME it culprit is an inaccurate chrono reading .</p><p></p><p> Example, I originally chronographed my 338 Lapua with the 300 SMK and came up with 2820 FPS average velocity. Actual shooting revealed that my drops were 6.4 inches low at 975 yards. Next I ran the BC up to .830 (.768 is Sierra's listed BC) and this did not solve my problem</p><p> Next I decided to recheck my zero and to re-chrono my load at the same time and this time I came up with 2791 FPS average velocity. Using 2791 FPS my drops were spot on and I have not experienced another problem</p><p> I was using an Olher 35 the difference was the lighting one day was very bright and sunny and the other day was overcast. The overcast readings were more accurate. That was an error of only 29 FPS and that was the problem</p><p></p><p> ExBall will allow you to trajectory validate the program and this adjusts velocity not BC</p></blockquote><p></p>
[QUOTE="jwp475, post: 244672, member: 3776"] IME it culprit is an inaccurate chrono reading . Example, I originally chronographed my 338 Lapua with the 300 SMK and came up with 2820 FPS average velocity. Actual shooting revealed that my drops were 6.4 inches low at 975 yards. Next I ran the BC up to .830 (.768 is Sierra's listed BC) and this did not solve my problem Next I decided to recheck my zero and to re-chrono my load at the same time and this time I came up with 2791 FPS average velocity. Using 2791 FPS my drops were spot on and I have not experienced another problem I was using an Olher 35 the difference was the lighting one day was very bright and sunny and the other day was overcast. The overcast readings were more accurate. That was an error of only 29 FPS and that was the problem ExBall will allow you to trajectory validate the program and this adjusts velocity not BC [/QUOTE]
Insert quotes…
Verification
Post reply
Forums
Rifles, Reloading, Optics, Equipment
Rifles, Bullets, Barrels & Ballistics
Problem with accurate readings from ballistics progs.
Top