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
Long Range Scopes and Other Optics
Favorite anti-cant level
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="Hugnot" data-source="post: 2800709" data-attributes="member: 115658"><p>Horizonal error;</p><p></p><p>[URL unfurl="true"]https://www.ssusa.org/content/effects-of-cant/[/URL]</p><p></p><p>Level the reticle;</p><p></p><p>[URL unfurl="true"]https://www.realavid.com/product/level-right-pro/[/URL]</p><p></p><p>I have found that placing a bubble level on top of the elevation dial does not assure a level or plumb reticle.</p><p></p><p>Using the info in the first attachment:</p><p></p><p>The midrange trajectory of the pointy 140 grain Hornady ELDM bullet, having a sight height of 1.7 inches, MV of 2950 fps, at 1000 yards is close to 90 inches (my 6.5-06). The estimator for a line of sight thru bore is 4 times the mid-range trajectory or 90 * 4 = 360 inches (dimension PT). The calculation for a 3 degree cant would be the line of sight displacement * sine of the cant or 360 * .052 = 19 inches horizontal. The vertical displacement is negligible. This is another factor to consider when shooting deers & such at long range like 1000.</p><p></p><p>For a shot at a pop can size rodent at 650 yards with a easily overlooked 1 degree cant using a 87 Vmax at 3475 fps at 650 yards - the mid range trajectory is 26 inches > 26 * 4 = 104, sine 1 degree = .017, 104 * .017 = 1.8 inches. Another factor in addition to wind. The rodent target would be somewhat less than 4 inches wide - wait until they are belly to dirt before taking the shot - most misses are left/right.</p><p></p><p>Upon leveling the reticle install the bubble level thingy on the scope. Placing a level on top of the elevation dial/knob won't work so good if the reticle is tilted in relation to the adjustment knob/dial. Some of my Leupold scopes are affected with tilted reticles.</p></blockquote><p></p>
[QUOTE="Hugnot, post: 2800709, member: 115658"] Horizonal error; [URL unfurl="true"]https://www.ssusa.org/content/effects-of-cant/[/URL] Level the reticle; [URL unfurl="true"]https://www.realavid.com/product/level-right-pro/[/URL] I have found that placing a bubble level on top of the elevation dial does not assure a level or plumb reticle. Using the info in the first attachment: The midrange trajectory of the pointy 140 grain Hornady ELDM bullet, having a sight height of 1.7 inches, MV of 2950 fps, at 1000 yards is close to 90 inches (my 6.5-06). The estimator for a line of sight thru bore is 4 times the mid-range trajectory or 90 * 4 = 360 inches (dimension PT). The calculation for a 3 degree cant would be the line of sight displacement * sine of the cant or 360 * .052 = 19 inches horizontal. The vertical displacement is negligible. This is another factor to consider when shooting deers & such at long range like 1000. For a shot at a pop can size rodent at 650 yards with a easily overlooked 1 degree cant using a 87 Vmax at 3475 fps at 650 yards - the mid range trajectory is 26 inches > 26 * 4 = 104, sine 1 degree = .017, 104 * .017 = 1.8 inches. Another factor in addition to wind. The rodent target would be somewhat less than 4 inches wide - wait until they are belly to dirt before taking the shot - most misses are left/right. Upon leveling the reticle install the bubble level thingy on the scope. Placing a level on top of the elevation dial/knob won't work so good if the reticle is tilted in relation to the adjustment knob/dial. Some of my Leupold scopes are affected with tilted reticles. [/QUOTE]
Insert quotes…
Verification
Post reply
Forums
Rifles, Reloading, Optics, Equipment
Long Range Scopes and Other Optics
Favorite anti-cant level
Top