General discussion question

I recently acquired some really nice bullseye firearms. I purchased these because they all had iron sights and all had been previously accurized.

My question to you guys is this..... What is the best way to "sight" a new to me firearm in ?

I am nearsighted and wear corrective lenses, should I start with a white sheet and a black cross in the middle from a sandbag or from my own right hand in shooting stance.

At what distance will be optimal ? 50 foot because we are indoors this time of year, or 25 yard as an average of both indoor and out ? My range supports 75 foot depth.

The first test run to be sure each gun was solid I found myself elevating the point of contact and shifting the windage to the right. 

Thanks in advance.

Shooting from a sandbag verses offhand you will usually get 2 different Points Of Impact.  How much different depends on the individual.  You could always use the sandbag to verify accuracy and as a starting point, but you should dial it in offhand.
- Dave

I sight it in based off of groups I shoot off hand. Like a match. Shoot five good ones and look. Make an adjustment and go again. But that's just me.

Zero your pistols offhand at 25 yards. Shooting off bags will not give the same zero. Know your adjustment for 50 yard, usually 2-3 clicks for 22 and 3-5 for 45.

zanemoseley wrote:Zero your pistols offhand at 25 yards. Shooting off bags will not give the same zero. Know your adjustment for 50 yard, usually 2-3 clicks for 22 and 3-5 for 45.

Not to hijack the thread, but the point of impact for a .22 at 25 yards and at 50 yards is exactly the same.  You should not have to adjust your sights from the long line to the short line.

cdrt wrote:

zanemoseley wrote:Zero your pistols offhand at 25 yards. Shooting off bags will not give the same zero. Know your adjustment for 50 yard, usually 2-3 clicks for 22 and 3-5 for 45.

Not to hijack the thread, but the point of impact for a .22 at 25 yards and at 50 yards is exactly the same.  You should not have to adjust your sights from the long line to the short line.

Is this due to the FPS speed ?
Good info, thanks

A std velocity .22 bullet is traveling (arcing) "up" to the 25 yard line, it peaks and then is going "down" to the 50 yard line, so the point of impact is the same.

Cdrt, Iron sights with a 6:00 hold?   If so, then I could understand that you don't have to change zero because the bottom center of the bull is higher at 50yd.  Since I shoot with red dot and center hold, I do have to have to adjust between the two.  I looked on SK's web page and (depending on velocity of the round and length of barrel) the drop between 25 and 50 yds varies between .4" and 1.1".  download SK brochure

Am I missing what you meant?

If you zero while the bullet is arcing up at 25 yards, then there is a chance you can be at near zero again at 50.

http://www.gunsmoke.com/guns/1022/22ballistics.html

The second half has a trajectory of a 1070 fps round.

I don't adjust my sights for 22 at 50 yards. Ballistics may say the group centre will be a half inch lower, but if my gun groups into an inch and my hold is 4 inches on a good day, the difference is pretty negligible...

Interesting.   It seems like the sight's angle to the bore and the height above the bore impact the relationship between where you zero and the arc.  Depending on the relationship between the sights and bore, you may have to adjust one pistol and not another from 25-50yd, even though both are shooting the same ammo.  

I can imagine a hypothetical pistol with sights exactly aligned with bore and compare that to another imaginary pistol with sights 12" above the bore.   If I was good at a graphics program, I could draw how the arc on both pistols "re-zeroed" at different distances.

"...the bottom center of the bull is higher at 50yd."

???  The 50yd bull is bigger, so the bottom is further from the center, which would translate to lower.

As to trajectory, the length of barrel really only has an effect on the velocity and the velocity is what determines the trajectory, which is not a true arc, but an arc of diminishing radius due to the slowing of the bullet as it gets nearer to the target.  There are many factors involved and the two most relevant are velocity and height of sighting system above the bore.  The lower the sights, the closer the first crossover, where the bullet is traveling upward in relation to the sight line.  On my 208s with dot, IIRC, the dot is about one inch above the bore and I do not normally adjust for any of my shooting distances with standard velocity ammo.

The bore has to point upward in relation to the sight line in order for them to be capable of reaching a zero.  This is because the bullet is falling, compared to the bore, as soon as it leaves the muzzle.

I once gave a lecture on ballistics a fascinating subject, at least to me.  Ed petty much nailed it and with a 22 LR at standard velicity it is petty basic.  Don

I shoot center mass,  but if you shoot a sub 6 then you also have to consider the distance from the bottom of the bull (or your hold) to the center. 4.0" (50yd) & 2.77" (25yd) target.

As stated above how much you have to change your sights ALSO depends how far above the bore center line they are.  

When I changed the optic from a Matchdot II with low mounts to an Aimpoint H1 that sits much lower I had to adjust (my adjustments) accordingly.
- Dave

Aprilian wrote:Cdrt, Iron sights with a 6:00 hold?   If so, then I could understand that you don't have to change zero because the bottom center of the bull is higher at 50yd.  Since I shoot with red dot and center hold, I do have to have to adjust between the two.  I looked on SK's web page and (depending on velocity of the round and length of barrel) the drop between 25 and 50 yds varies between .4" and 1.1".  download SK brochure

Am I missing what you meant?

Whether irons or dot, I do not adjust my sights on the .22 from the 50 yard line back to the 25 yard line.

Ed Hall wrote:
???  The 50yd bull is bigger, so the bottom is further from the center, which would translate to lower.

All I can claim is that perhaps it was before the caffeine kicked in?   You are of course correct sir.

Theory makes for interesting discussion.  Lots of variation in application from person to person.   Me?  From 25 to 50?  Up 4 clicks with the 22.  Up 8 clicks with the 45 WC gun...

50 foot indoor stuff kills me...  I have significant windage changes from 50 foot indoor to 75 feet outdoor.

Worthwhile to note...  While we talk about sight alignment and sight picture and use the same words,  we do not see exactly the same thing or control the gun the same.  Exactly why when a shooter asks me to zero his gun I make it plain that I can get him on paper but the fine tuning is a very personal thing.

cdrt wrote:

zanemoseley wrote:Zero your pistols offhand at 25 yards. Shooting off bags will not give the same zero. Know your adjustment for 50 yard, usually 2-3 clicks for 22 and 3-5 for 45.

Not to hijack the thread, but the point of impact for a .22 at 25 yards and at 50 yards is exactly the same.  You should not have to adjust your sights from the long line to the short line.

Disagree, I’m down 2 clicks coming to the short line with my 22  And an aimpoint

The only time the POI is the same at 25yd & 50yd is when your sight center line is 2" above the bore and you zero at 50yd.
If sight is 1.5" above the bore the 25yd POI will actually be 0.3" higher than the 50yd POI


If you zero at 25yd 
1.5" sights = 0.6" drop at 50yd
2" sights = 0.1" drop at 50yd

If you zero at 50yd 
1.5" sights = 0.3" rise at 25yd
2" sights = 0.0" change at 25yd

In either case once I have my 22 zeroed at 50yd I don't change my sights on the 25yd line.
-Dave
of course if my POI is different for today's match due to ???? then I adjust.

Theory and application...  Don't assume anything.  Do what works for you.  Iron sights, red dots, and scopes, I adjust.   The master class military shooters that taught me started it for me.  They told me and I believed.  Worked good enough for me to shoot iron sight 2600 scores when holding an expert classification card in '84.

If you cant the gun some when shooting it will change the POI both in elevation and windage.  Think of the dot being the center of the circle and the bore the outer edge.   Sighted in 100% vertical puts the bore at 6 o'clock on the circle.  A little cant to the left moves the bore right and up.  The higher the dot above the bore the more the movement.  Levels are often put on rifle scopes and some scopes have build in indicators.   I have levels on my Matchdots that I shoot benchrest pistol with trying for one hole groups indoors.  Don

Within reason, the human effect is larger than the cant effect.

Magload wrote:If you cant the gun some when shooting it will change the POI both in elevation and windage.  Think of the dot being the center of the circle and the bore the outer edge.   Sighted in 100% vertical puts the bore at 6 o'clock on the circle.  A little cant to the left moves the bore right and up.  The higher the dot above the bore the more the movement.  Levels are often put on rifle scopes and some scopes have build in indicators.   I have levels on my Matchdots that I shoot benchrest pistol with trying for one hole groups indoors.  Don

What you descibe is at the gun and is counter-intuitive, since canting to the left actually moves the bullet hit on target left and down due to the sight line and bullet drop differences.  I have an article detailing this at:

Pistol Shooting: The Art (Part 12)