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My iron sights are hitting about 1.5in left at 25. These are suppressor height and I have a RMR.

Do I move the rear sight to the right? Is it worth moving for and inch?

I was playing around with a sight pusher and it very difficult to tell if I even moved the sight. Is there a way tell?


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Posts: 4613 | Location: Pittsburgh, PA, USA | Registered: February 27, 2001Reply With QuoteReport This Post
Oriental Redneck
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If POI is left, move rear sight to right.
If POI is right, move rear sight to left.

In other words, move rear sight in the direction you want the POI to move to.


Q






 
Posts: 21150 | Location: TEXAS | Registered: September 04, 2008Reply With QuoteReport This Post
Freethinker
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quote:
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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Posts: 43823 | Location: 10,150 Feet Above Sea Level in Colorado | Registered: April 04, 2002Reply With QuoteReport This Post
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Just this one gun? If not, check your grip.


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Posts: 1035 | Location:  | Registered: March 28, 2007Reply With QuoteReport This Post
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I take it you are shooting from a GOOD rest and not moving or jerking at all, if this is the case I would adjust my sights.
 
Posts: 16 | Registered: December 22, 2009Reply With QuoteReport This Post
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Glock 17 with ameriglo sights.

I did not have the best rest. Mag resting on a railroad tie and the frame on a rolled bath towel lol.

When I align my iron sights my red dot is slightly left.

I will have to try pencil mark. Too bad I don’t have any more HD ammo to shoot. My ball ammo hits about an inch low compared to HD.


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Posts: 4613 | Location: Pittsburgh, PA, USA | Registered: February 27, 2001Reply With QuoteReport This Post
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1.5” left at 25 yards? Dang, what kind of groups are you getting that you can discern 1.5” at 25 yards?




"Those who would give up essential Liberty, to purchase a little temporary Safety, deserve neither Liberty nor Safety." - B.Franklin
"Wrong does not cease to be wrong because the majority share in it." L.Tolstoy
 
Posts: 9320 | Location: In the gilded cage | Registered: December 09, 2007Reply With QuoteReport This Post
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quote:
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: 1161 | Location: Oregon | Registered: March 18, 2014Reply With QuoteReport This Post
Freethinker
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quote:
Originally posted by dehughes:
Even better than a pencil mark is the edge of a brass rod or punch ....


Thanks for that tip.




“To argue with a person who has renounced the use of reason is like administering medicine to the dead.”
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Posts: 43823 | Location: 10,150 Feet Above Sea Level in Colorado | Registered: April 04, 2002Reply With QuoteReport This Post
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quote:
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?


I'm with Konata88 in asking the question....plus I'd leave the sights right where they are and hold right 1.5".
 
Posts: 236 | Location: Central Ohio | Registered: January 05, 2018Reply With QuoteReport This Post
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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: 3974 | Location: Iowa | Registered: February 24, 2011Reply With QuoteReport This Post
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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: 220 | Location: SE Pennsylvania | Registered: August 27, 2001Reply With QuoteReport This Post
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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.




"Those who would give up essential Liberty, to purchase a little temporary Safety, deserve neither Liberty nor Safety." - B.Franklin
"Wrong does not cease to be wrong because the majority share in it." L.Tolstoy
 
Posts: 9320 | Location: In the gilded cage | Registered: December 09, 2007Reply With QuoteReport This Post
Lost
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The formula for sight adjustment is: (Error ÷ Distance) x Sight radius = Correction amount.

So with a 6.5" sight radius: (1.5" ÷ 900") x 6.5" = .011", or about 0.28 mm.

You would move your rear sight about eleven-thousandths of an inch to the right. This is like 3 or 4 hairs' width.



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Posts: 14058 | Location: SF Bay Area | Registered: December 11, 2003Reply With QuoteReport This Post
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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.
 
Posts: 2213 | Location: Greenville, SC | Registered: January 30, 2017Reply With QuoteReport This Post
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25 yards? Kkina has it, .011".
25 FEET? move sight .032".

What does it matter what somebody else does?
How much practice are you willing to do to learn a new grip and finger?
 
Posts: 2956 | Location: Florence, Alabama, USA | Registered: July 05, 2001Reply With QuoteReport This Post
Lost
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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. Big Grin

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.



ACCU-STRUT FOR MINI-14
"Pen & Sword as One"
 
Posts: 14058 | Location: SF Bay Area | Registered: December 11, 2003Reply With QuoteReport This Post
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quote:
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?


Let me clarify I’m in no way shooting 1” groups. The average of my shots could benefit by moving an inch and a half.


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Posts: 4613 | Location: Pittsburgh, PA, USA | Registered: February 27, 2001Reply With QuoteReport This Post
SIGSauer
Anthropologist
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quote:
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: 3664 | Location: Switzerland | Registered: January 24, 2001Reply With QuoteReport This Post
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First thing I'd do is move the target in to 10 yards and get a good rest. A tight group is an absolute necessity to begin sighting in.
 
Posts: 274 | Location: Utah | Registered: August 30, 2007Reply With QuoteReport This Post
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