Originally posted by 12131: In other words, move rear sight in the direction you want the POI to move to.
Yes, that.
Depending upon the gun and sight, it may be possible to draw a fine pencil line along the base of the sight to serve as a witness mark to show how much the sight is moving (if at all). What gun and sight(s) do you have?
There are some mathematical calculation methods using trigonometry that can be used to determine how much a sight must be moved to achieve the desired point of impact, but they require some exact and difficult-to-impossible measurements, so I’ve never been successful except with trial and test. The pencil line can be used as a guide, though: move the sight enough to cover the line then test fire to see how much that changed the point of impact. Repeat with a new line if/as necessary.
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I can tell at sight a Chassepot rifle from a javelin.
Posts: 48296 | Location: 10,150 Feet Above Sea Level in Colorado | Registered: April 04, 2002
1.5” left at 25 yards? Dang, what kind of groups are you getting that you can discern 1.5” at 25 yards?
"Wrong does not cease to be wrong because the majority share in it." L.Tolstoy "A government is just a body of people, usually, notably, ungoverned." Shepherd Book
Posts: 13563 | Location: In the gilded cage | Registered: December 09, 2007
Originally posted by konata88: 1.5” left at 25 yards? Dang, what kind of groups are you getting that you can discern 1.5” at 25 yards?
That’s not hard to determine. You take the average center of a group and measure its distance from the center of your aiming point on the target, and there you are.
Even better than a pencil mark is the edge of a brass rod or punch used to mark the inside of the dovetail as a reference point for how much you move the rear sight. I have done this before with great success, as it gives you a nice clear point of reference.
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Posts: 1251 | Location: Oregon | Registered: March 18, 2014
As stated by another member, you take the center of whatever group you have to determine for far. 1.5" would be fairly easily identifiable at 25 yards with the gun benched.
Rear sight movements are always the same as the direction desired, fronts are opposite. The acronym FORS (front opposite, rear same) is easy to remember.
Posts: 5351 | Location: Iowa | Registered: February 24, 2011
Almost every gun I pick up shoots to the left in my hand. It may be trigger manipulation or grip but I find it simpler to adjust the sight. Having done that, if I shoot the gun left handed the variance is lessened but the gun shoots to the right. The guns seem to shoot away from my gripping palm.
Posts: 248 | Location: SE Pennsylvania | Registered: August 27, 2001
Depending on the sight radius, how much are we talking about moving the sight? 0.5mm?
Are the groups repeatable day in day out?
Pretty awesome if one can consistently shoot tight enough groups at 25 yards where one inch matters.
"Wrong does not cease to be wrong because the majority share in it." L.Tolstoy "A government is just a body of people, usually, notably, ungoverned." Shepherd Book
Posts: 13563 | Location: In the gilded cage | Registered: December 09, 2007
I would do two things first.... have someone else shoot the pistol and see where their groups land and also try centering your finger on the trigger. personally I would not try to 'correct' 1.5" at 25ft.
The reason I say this is the Romeo sight on my P320 showed me that the sight picture would move to the left just about that much if my finger was not centered exactly on the trigger.
If I'm reading your second post correctly, your RDS is correctly sighted to POI, which does suggest your iron sights are a hair off. It's up to you whether you want to adjust it. Since you already have a sight pusher, I would probably go for it, but then I tend to be pretty OC.
Of course, if your optical sight is correct, adjusting your irons is easy- just shift your rear sight until it lines up with the red dot. Co-witness is your friend.
Originally posted by konata88: Depending on the sight radius, how much are we talking about moving the sight? 0.5mm?
Are the groups repeatable day in day out?
Pretty awesome if one can consistently shoot tight enough groups at 25 yards where one inch matters.
sight adjustment and group size don`t relate to each other. you can calculate the personal off / deviation form the center of target with any group size.
A 1.5" adjustmet at 25yds with a conventional M3 rearsight spindle would be 2 to 3 clicks. It´s pretty common in target shooting to adjust such errors during an exercise of competition.
Using a sight adjstment tool with an M3 spindle would take approixiately have a revolution to get the front in line again.
Posts: 3795 | Location: Switzerland | Registered: January 24, 2001