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Pond, James Pond
April 11, 2014, 05:04 PM
I just know this is one of the most basic questions, and I should feel ashamed for asking it.

As luck would have it I have no shame, so I'm asking. :o

When I zero'ed my scope for my usual ammo I aimed at the centre, fired, then put the rifle in a support, and proceeded to adjust the scope so that the cross hairs crept over from the centre to the bullet hole.

When I did that, I remember seeing the little arrows on the turrets directing "this way for up" or "this way for down", yet when I turned them to move my POA to my POI, they went in the opposite way to where I expected.

They seemed to work in a completely counter intuitive way.
Does UP have a different meaning when adjusting scopes?!

Why is that?

Pahoo
April 11, 2014, 05:19 PM
You are not losing it and this is a common occurrence. It all depends on the scope. In most American made scopes, if you want to raise the point of impact, on the target, you follow the directions of the UP arrow. Then there are other scopes that you do the 180. I've read that the actual operation or norm, is as yours works and too many folks were confused, so scope manufactures just labeled them the opposite. .... :confused:

Be Safe !!!

Double Naught Spy
April 11, 2014, 05:20 PM
You fired and THEN put your rifle in a support? That sounds backwards as well.

g.willikers
April 11, 2014, 05:52 PM
On my scopes the reticle acts like a nut on a threaded bolt.
Turn the adjuster clockwise and the crosshair moves toward the adjuster.
Think Nut and Bolt.
Unless, of course, it goes the other way.
But none of mine do.

AK103K
April 11, 2014, 05:56 PM
I agree with Pahoo, youre not going crazy. :)

I was helping my buddy sight in a couple of his rifles last week, and "up" was up on one, and down on another. Same difference with the "right" arrow.

I always just bore sight mine by looking down the bore and bringing the cross hairs onto what Im looking at in the bore. So far, its always got me on paper.

As far as adjustments go, I always go with the aggressive method I was taught with my irons on my M1's. Better to go past and come back, than to creep your way across. Its faster with less wasted rounds. With the contrary "arrows" on your turrets, it also tells you pretty quick what is what.

Brian Pfleuger
April 11, 2014, 07:02 PM
Think about it.... they have to move the reticle the opposite way.

You have fired a bullet and now find that the hole is below the aim point. In order to raise the spot where the bullet hit, you must raise the barrel angle. That means lowering the reticle.

Or, consider that since the bullet hole is low, it will be BELOW the reticle. If "up" raised the reticle, it would get FARTHER away, not closer.

It's always that way when you're moving a "front" sight. Archery, for example... the rear sight is fixed. The front sight moves. If you're shooting left, you move the pin left.

Since you're not normally LOOKING through a scope when you make the adjustment, they just label it for the EFFECT it has, not the direction it's moving the sight.

AK103K
April 11, 2014, 07:15 PM
Think about it.... they have to move the reticle the opposite way.
Youre absolutely right. The problem is, the makers seem to be confused. :)

Its sort of like the one range I used to be long to. They used a red, yellow, and green flag system. It was a "sportsmans" club, and it seems none of them had ever been on a military range. Red to them meant "safe", or "stop shooting", for quite a few of us who joined later, it was pretty confusing for awhile. The color system was directly opposite to what was beat into out heads as kids. Red means danger. Green was safe. :)

Now, is up down or down up? In the immortal words of Vinnie Barbarino...."Im soooo confused!"

Pahoo
April 11, 2014, 07:22 PM
Since you're not normally LOOKING through a scope when you make the adjustment, they just label it for the EFFECT it has, not the direction it's moving the sight.
Thank you for expressing it better than I did. I have seen many European scopes that work in this manner and American scopes that dealt with the EFFECT. .... :rolleyes:

Be Safe !!!

PetahW
April 11, 2014, 07:26 PM
.

You're not going crazy, but not for the reasons posted above.

The difference is that:

1) Moving the reticle from the center of the target to the bullet hole (moving the POA)

is the direct opposite of

2) Moving the bullet hole to the to the center of the reticle/target (moving the POI).

(Old guys know "stuff" ;) )


.

Pond, James Pond
April 12, 2014, 01:47 AM
You fired and THEN put your rifle in a support? That sounds backwards as well.

It is a support for cleaning, not a clamp for shooting. I made it from three left over bits of fibre-board from the kitchen refit....

So I shoot, seated, then use the rest as a stable platform, on the table I shot from, to then adjust from, peering through the scope to track the reticle's position but trying not to touch/jolt the rifle. Repeat until POI = POA.
Not so backwards.

As for the adjustment on what is a Burris XTR, I think Brian's take in the logic that needs to be applied but also PetahW's little reversal guide probably explain where my confusion stemmed from. So the trick is partly to stick to either POA to POI or vice versa, but not mix and match!

Thanks!

Once I decide on which bullet to use as my standard practice round (at least two more OCW runs to do) then I will re-zero to suit!!

Picher
April 12, 2014, 07:33 AM
I have a Sweeney Sight Vise that I use when adjusting newly-mounted scopes. It's screw-adjustable for elevation, but windage is done by moving the rear of it on the bench. Rifles can be shot when locked in to the vise, but I don't do that, preferring to use a regular benchrest setup.

Many adjustments marked 1/4" @ 100 yards were found to be up to 1". Cheap Red-Dot sights are often backwards, but being made in China, that may be understandable. LOL

The rig not only saves ammo, but allows for adjustment clicks that either weren't accurate, or knob markings that are opposite from the way POI was to be moved on-target. And yes, when using it, correct adjustment knobs are turned opposite to markings to make the image coincide with bullet strikes. (That's because you're moving the reticle image to coincide with the desired bullet strike instead of moving subsequent bullet strikes to the aiming point, which is what adjustment knobs are designed to do.)

123kiwi
April 26, 2014, 11:36 PM
Move the bullet not chase the bullet...

Pond, James Pond
April 27, 2014, 02:29 AM
Move the bullet not chase the bullet...


That sounds like an easy little rule to remember, but....

Can you explain what that means in real-life terms for me?
:)

green_MTman
April 27, 2014, 03:08 AM
fire three shots and after that ajust the scope away from the error and towards the target.the scopes manual should explain how to do that

NHSHOOTER
April 27, 2014, 07:22 AM
After all is said and done, I agree with green_MTman. I find it easier to shoot and chase the target rather than chase bullet holes..just my opinion.

Pond, James Pond
April 27, 2014, 08:18 AM
Let's say I aim at the X of a target, for example, and then say the shots land upper right, 3" away, meaning that at 100yds, I'd need to move the cross-hair by 6 clicks (1.5 MOA) horizontally and 6 vertically.

What I would normally do is put my gun in the support, adjust it so that the reticle is on the X and then use the turrets to move the reticle toward the bullet hole. However, this usually means I am having to turn the turrets in the opposite direct to that which is written on the turret heads.

That would be chasing the bullet hole, and the method you recommend against, right?

So can you explain how to chase the target in similarly simple language?

This must seem terribly obvious, but my head just gets very muddled with this sort of logic...

Husqvarna
April 27, 2014, 08:57 AM
you adjust the sight so you get a group at POA

or if you are hunting you have POI a couple of cms above

but being made in China, that may be understandable. LOL
well duh china is on the opposite site of the world

44 AMP
April 27, 2014, 10:14 AM
The usual convention is that the turrets are marked to move the bullet strike where you want it to go (from the shooter's point of view).

Using your example of the bullets hitting high and right 3"....

Using the knobs, you would turn them to move the bullet down, and left those 3".

What this does inside the scope is move the crosshairs up, and right.

USUALLY the markings on the turret are to move the bullet hole on the target, BUT, it is possible they are the directions the crosshairs actually move when the turret is turned. This is the exact opposite of what you want if you think you are moving the bullet strike.

Makers instructions should be clear, but might not be. Two shots (or groups, if you prefer) will tell you which way you need to go, no matter what the markings are.

I have also found that on some scopes the markings about how much each click moves the bullet are more like guidelines than rules....

Here's a little test, (usually) not something vital, but nice to know...

Say you figure out you want to go 6 clicks in some direction. Some folks will go the 6 clicks and shoot. Some will go 8 clicks, and then back 2, then shoot.

The numbers are just for illustration. I have seen scopes that will put the bullet in a slightly different place if you go past, and then back to the desired setting.

Also, while it shouldn't happen, some will shift the point of impact slightly as magnification is changed.

Art Eatman
April 27, 2014, 10:33 AM
I've boresighted rifles from my dining table, removing the bolt, looking out the window at some fixed object, and twiddling the crosshairs until they are fairly close to what I see through the bore. You don't even have to know what L, R, U and D mean; just twiddle until something good happens. Books and a towel make as good a support as necessary.

Okay, now to the real deal. I draw a cross on a sheet of typing paper for a target and tape it to a cardboard box. I set it at some 25 steps from my benchrest.

I fire one shot. If the bullet hole is left of center, I turn the knob "R" and shoot again. Similar twiddle for high or low. Since I've been doing this for sixty years, it rarely takes more than three shots to be dead-center. Think of it as adjusting a rear sight on an iron-sighted rifle.


Okay. Now for 100 yards. Commonly, dead-center at twenty-five yards is about three inches high at 100 yards, and easily two or so inches to either side.
I shoot three-shot groups for sight-in, adjusting the apparent group center until I'm at the desired height above the aiming point. For me, for almost all rifles, that's two inches high at 100 yards.

If the rifle, scope and ammo are all new to me, I'll use five-shot groups in testing for accuracy. Aside from testing of loads, it indicates whether or not I need to tweak with the bedding. Once I'm satisfied, I use three-shot groups for checks of sight-in. I'm a hunter, so the most important factor of all is that the first shot from a cold barrel always goes to the intended point of impact.

So far, so good. :)

Pond, James Pond
April 27, 2014, 01:51 PM
USUALLY the markings on the turret are to move the bullet hole on the target, BUT, it is possible they are the directions the crosshairs actually move when the turret is turned. This is the exact opposite of what you want if you think you are moving the bullet strike.

Good description, that one!!

Despite that, my brain requires I read it another 3 times, slowly, before I can work it out... :o

As for the scope, it is a Burris XTR 312.

I want to use the turrets for distance adjustments rather than hold-over and the turrets are designed to be adjusted regular: big, with lots of graduations and dust-caps so meant to be used, rather than set and left.

So I hope the turrets are accurate and consistent in their adjustments.

In fact, I'd like to learn both techniques.

Gunplummer
April 27, 2014, 05:29 PM
This was real common when imported (Cheap) scopes hit the market years back. I remember some early Japanese imports doing this. Who knows where a scope or parts for it are made now? A lot of real complicated answers. Good thing you did not ask about open sights.

hornetguy
April 27, 2014, 09:02 PM
It's simple.

The arrows that point to "up" or "down" are telling you which way to turn the knob to change the point of impact of the bullet.
In order to change the point of impact "up", the crosshair has to go down.

Your confusion came from the idea that "up" or "down" was referring to the reticle, not the point of impact of the bullet.

Bottom line: The reticle will move in the opposite direction from the change in bullet point of impact.

jimbob86
April 27, 2014, 09:17 PM
The arrows that point to "up" or "down" are telling you which way to turn the knob to change the point of impact of the bullet.
In order to change the point of impact "up", the crosshair has to go down.

It's a whole lot simpler if you don't watch the reticle move when you make adjustments.

Shoot your group @100 yards on paper, aiming at whatever is your aiming point.

Most of the scopes I've seen move the reticle 1/4" @100 yards.....

The center of your group was 3" high and right? Move the scope 12 clicks in the "down" ( some of the cheaper scopes should be moved a few clicks past desired amount and then back, in the direction of the arrow- taking out backlash) and then 12 left ..... shoot again at the aiming point......

jmstr
May 1, 2014, 12:40 PM
There's been a lot of good 'sighting in' advice here already, regarding moving the POI to the POA by repeating the procedure of [shoot, identify hi/low and distance, adjust, repeat].

The only thing I have to offer from my experience is that I do a 3 shot group for each one of those.

I am NOT a good shot. As such, my breathing and trigger control are spotty.

One shot to use for measurement isn't always helpful. That could be one I 'pulled' without knowing it.

I take the average spot of the 3 shot 'mini-group', and then I adjust my scope.


The best way I've found to do this is with a 20-60 power spotting scope and a friend to identify where they are going. They watch on 50 or 60 power as to where my shots go and advise me after I finish my group of 3. I then adjust my 4 power scope [or my 8-24 on another rifle] to get closer to my desired poi.

The friend I go with is kind of new. I had a tough time convincing him that, yes, I wanted my POI to be about 1.5-2" ABOVE the centerpoint of the bullseye at 100 yards. He was trying to get me to hit it directly on the X marks the spot at 100 yards.

Finally he got the point I was going for, regarding 2" high at 100 yards being close to spot on at 200 yards with my .308 or .300 savage.

You can do it with the spotting scope while alone also, btw.

Just a thought.

And then, dial in that big old .44mag revolver at the same distances?

What rifle is this, btw?

Pond, James Pond
May 1, 2014, 01:31 PM
What rifle is this, btw?

A CZ550 Varmint in .308 with a Burris XTR 312 scope and a Harris bipod.

I like it! Looks cool and makes me look like I know what I am doing: hence why I always make sure no one is around when I practice: why burst the bubble?! :D

jmstr
May 1, 2014, 04:45 PM
A CZ550 Varmint in .308 with a Burris XTR 312 scope and a Harris bipod. Nice!:D

Do they regulate/block ownership of semi-auto rifles over there? Just curious.

If I can convince my wife that one more rifle would be just fine, I want to get a .308 bolt. I've got the Savage 99 in .308 [1957 model-no detachable magazine], as well as a Saiga and a Garand. Now time for a bolt and a pump!

I like the looks of the CZ, and the quality is well respected!

Have you been doing more long-gun fun lately? I remember a lot of questions on revolvers and semi-auto handguns last year [or was it the year before].

We all go through phases. I'm using my rifles more this past year also.

Enjoy!

tomrkba
May 1, 2014, 07:19 PM
Read the fine manual that came with the scope.

45_auto
May 2, 2014, 08:55 AM
It's POI vs POA.

What I would normally do is put my gun in the support, adjust it so that the reticle is on the X and then use the turrets to move the reticle toward the bullet hole. However, this usually means I am having to turn the turrets in the opposite direct to that which is written on the turret heads.

You need to reverse your thinking. Consider it to be moving the bullet hole to the crosshairs instead. The turrets are marked to move the POI but you're using them to move the POA.

Let's say I aim at the X of a target, for example, and then say the shots land upper right, 3" away, meaning that at 100yds, I'd need to move the cross-hair by 6 clicks (1.5 MOA) horizontally and 6 vertically.

What I would normally do is put my gun in the support, adjust it so that the reticle is on the X and then use the turrets to move the reticle toward the bullet hole. However, this usually means I am having to turn the turrets in the opposite direct to that which is written on the turret heads.

Per your own description above, "shots land upper right", your example shot was 3" high and 3" right. While looking through the scope, if you move the turrets 6 clicks in the marked DOWN and LEFT directions (directions you desire the bullet to move), the crosshairs will magically RISE 3" and move 3" RIGHT and be directly on top of your bullet hole. This is what you're seeing and why the turrets appear reversed to you. You're thinking the crosshairs have to move UP and RIGHT to the bullet hole, while the scope makers are thinking that the bullet hole has to move DOWN and LEFT to the crosshairs. It has to work that way, because of what you say below:

I want to use the turrets for distance adjustments rather than hold-over and the turrets are designed to be adjusted regular: big, with lots of graduations and dust-caps so meant to be used, rather than set and left.

Let's say you zeroed your scope at 100 yards. POI = POA at 100 yards.

Now you want to hit the bullseye at 1,000 yards. Let's say that your bullet needs to strike 3" high at 100 yards to be zeroed at 1,000 yards. If you turn your turret 6 clicks in the "UP" direction, as marked, it will raise your POI the required 3" at 100 yards. If you were looking through your scope as you did this, you would see the crosshairs move 3" DOWN (opposite the turret markings) on the 100 yard target. When you move the rifle itself to put the crosshairs 3" back up onto the bullseye, the POI will be the required 3" high.

Just remember to turn the knobs in the direction you desire the bullet strike to move, NOT the direction you desire the crosshairs to move. Bullet needs to move UP, for example to shoot at a longer range, then turn turret in UP direction.

Just like adjusting a marked front sight. If you're shooting low and want the POI to move UP, then turn the sight in the direction of the arrow. Physically the sight will move DOWN (opposite what the arrow says, just like scope crosshairs). However, the lower front sight will cause the POI to move UP.

http://upload.wikimedia.org/wikipedia/commons/6/6a/M16_front_sight_post_P1010030.JPG

Pond, James Pond
May 4, 2014, 02:09 PM
Do they regulate/block ownership of semi-auto rifles over there? Just curious.

If I can convince my wife that one more rifle would be just fine, I want to get a .308 bolt. I've got the Savage 99 in .308 [1957 model-no detachable magazine], as well as a Saiga and a Garand. Now time for a bolt and a pump!

I like the looks of the CZ, and the quality is well respected!

Have you been doing more long-gun fun lately? I remember a lot of questions on revolvers and semi-auto handguns last year [or was it the year before].

We all go through phases. I'm using my rifles more this past year also.
Well, they sort of regulate everything in that I need a permit to buy any gun, even though I have already passed the exam and reviews to allow me to buy a gun.

Aside from that they do not regulate semis as they do in the UK. I could buy an AR, AK, Druganov, AR308 etc. The market is what really limits. For example, I quite like the Tavor or FS2000 bullpups, but no-one sells them and if they did if would be sell both my kidneys and one of my neighbour's to afford it. (Now that I think of it, make that two of my neightbour's and one of mine)

Another restriction is storage. I have reached storage limits for the safe I have. If I wanted to get more stuff, I either need to sell something or get a bigger safe. The latter is just not possible in my home and the former is not particularly appealing so no new guns for now. However, the semi and revolver phase is still going strong: is just an itch that I can't scratch...

Pond, James Pond
May 4, 2014, 02:11 PM
It's POI vs POA.

...

You need to reverse your thinking. Consider it to be moving the bullet hole to the crosshairs instead. The turrets are marked to move the POI but you're using them to move the POA.

Faaaantastic description!! :) Thanks!

I do need to reverse my thinking and it is a bit tricky as, previously, it was all stuff I had difficulty in visualising: if I can picture something, I can understand it far more easily.

Yours and some of the previous posts have helped address that!