Quick question on magnification

[Bankzi 2]

Zeroing my rifle in tonight, just a quick one - If i increase the magnification on my scope say just for a clearer view what will happen to my POI? I have a simmons prohunter 3-10x44 and was zeroing on mag 5, say i increased it to mag 10 for example what would change?

[tonyponty 6]

i will be interested in this as well ..

[tegater 789]

In theory nothing at all should change, but it does depend upon the quality of the scope. It always used to be good advice to zero on maximum magnification, as in most circumstances this is what you would shoot on. The reason being that poorer quality scopes, could not guarantee that the POI wouldn't change. Decent quality scope will not change the POI at any magnification, but the only way to know for sure, is to test it.

[zini 1,939]

Nothing will happen mate.

 

You can zero at any mag and then change it to what ever mag and nothing will happen to your POI.

 

What you will find is that your wobble will be magnified by what ever mag you change to.

 

The only way the change of mag has an effect on POI is when you change distance from your zero range, i.e zero on x10 at 25 metres then change to x4 or 6 for night time shooting and shoot at various ranges other than your zero range.

 

A change in mag (higher) means than your mildot hold over and under points become larger and a change in mag (lower) means that your points become smaller, i.e

 

Zero at 25m x10

 

Shoot at a target at 35 metres on x10 and you may have to hold over 1 1/4 mildots

 

Change to x4 and you may only have to hold over 1/4 of a mildot

 

Change to x16 and you may need to hold over 1 3/4.

 

Hope this all makes sense buddy.

 

Si

Edited September 15, 2011 by zini

[secretagentmole 1,701]

Another piece of advice is to download BRC or Chairgun from Hawke, put in your rifle's fps and the pellet, then increase and decrease the magnification, you will see how the mil dots/scope markings will change in distance, but the zeroed distance will always remain the same!

[matt_hooks 188]

Not always true Si. Depends if the reticule is on the first (front) focal plane or the second(rear). If it is ffp, then zooming will not change the reticule size in relation to the target, so your mildot compensations at each distance will be the same. If it's second (or rear) focal plane, then the reticule is a fixed size to the shooter, and so you have to adjust hold over/under for different zooms.

 

All modern scopes should hold a constant POA at all zooms. Zeroing at highest mag is recommended, as you can set the point of aim more precisely. The amount of wobble is the same at all zooms, it is just more visible at higher zooms.

[tegater 789]

Not always true Si. Depends if the reticule is on the first (front) focal plane or the second(rear). If it is ffp, then zooming will not change the reticule size in relation to the target, so your mildot compensations at each distance will be the same. If it's second (or rear) focal plane, then the reticule is a fixed size to the shooter, and so you have to adjust hold over/under for different zooms.

 

All modern scopes should hold a constant POA at all zooms. Zeroing at highest mag is recommended, as you can set the point of aim more precisely. The amount of wobble is the same at all zooms, it is just more visible at higher zooms.

Correct. Which is why FFP scopes are better when using mil dot reticles or similar for holdover/holdoff. However I realise this is a different subject to the one being asked.

[zini 1,939]

Come on Matt me and you are not doing this again are we?

 

Read what i put mate,

 

What you will find is that your wobble will be magnified by what ever mag you change to.

 

Read what you put

 

The amount of wobble is the same at all zooms, it is just more visible at higher zooms (Why Matt)? Read on.

 

Zeroing / shooting at x4 is really easy with minimal wobble or you may think depending on the shooter, this wobble is noticable from your normal eye by x4 of what it would be on 0 mag. Zeroing / shooting at x14 means the wobble is magnified (IN YOUR EYES) and more visible like you have put in this case by x 14 from 0 mag.

 

Thats what i was getting at Matt just like you know i was .

 

Regarding scopes - Read what he wrote mate

 

He said a simmons prohunter 3-10x44.

 

This scope i know changes POI when zoomed and it has the Truplex reticle which are mostly 30 / 30 reticles, hence my answer buddy.

 

How many people do you know anyway with a scope these days that can say the zoom doesnt change POI? I know none and i bet you dont know many.

 

ATB

 

Si.

Edited September 15, 2011 by zini

[andyfr1968 772]

Reading some of the above shows why I prefer a fixed mag scope but there's very little available for airguns these days. IMO something like a 6x40something is perfect for airgun hunting and why my variable mag scopes hardly ever change from around 6 or 7.

 

Each to their own though, mag is largely personal choice.

Edited September 15, 2011 by andyfr1968

[andyfr1968 772]

Oops, double post

Edited September 15, 2011 by andyfr1968

[tegater 789]

Zeroing my rifle in tonight, just a quick one - If i increase the magnification on my scope say just for a clearer view what will happen to my POI? I have a simmons prohunter 3-10x44 and was zeroing on mag 5, say i increased it to mag 10 for example what would change?

Bankzi. The other thing you can do, is to test it, without firing a shot. Put your rifle in a rest / on sandbags etc, and chock it so that it wont move. (you will need to set it up so that the cross hair is fixed on a small aiming mark, and your mag set at 5x. (using your example) Once the rifle is chocked and on aim, and without moving the rifle, zoom in and you should find that the cross hair stays on the initial point of aim. (this means magnification zoom will not alter your POI)

 

If it doesn't then it will at least, highlight to you that there is an error in the scope and your POI will change. I will be suprised if it does, but not all scopes are made to the same standard.

 

It doesnt make any difference what distance you carry out this test, but for reassurance you zero range would be the ideal.

 

Good luck.

[gurtwurz 792]

Reading some of the above shows why I prefer a fixed mag scope but there's very little available for airguns these days. IMO something like a 6x40something is perfect for airgun hunting and why my variable mag scopes hardly ever change from around 6 or 7.

 

Each to their own though, mag is largely personal choice.

 

 

blimey andy, you shoot those extreme distances with simon on x6?!!

 

hat off to you mate, thats some sort of shooting

 

cheers, wurz

[andyfr1968 772]

Reading some of the above shows why I prefer a fixed mag scope but there's very little available for airguns these days. IMO something like a 6x40something is perfect for airgun hunting and why my variable mag scopes hardly ever change from around 6 or 7.

 

Each to their own though, mag is largely personal choice.

 

 

blimey andy, you shoot those extreme distances with simon on x6?!!

 

hat off to you mate, thats some sort of shooting

 

cheers, wurz

 

Thanks, Wurz.

 

My Diana wears a JSR 2-7x32 with a basic generic mil dot and my 90's got a Simmons 8 Point1.5-5x32, plain old 30-30. Thery're perfect for what I need them for but as I said above, each to their own

 

When I get the old Diana up and running again, it'll be topped off with an old Nikko 6x40 that I dug out a while back. I'd forgotten I had it!!

[Marksman 934]

Nothing will happen mate.

 

You can zero at any mag and then change it to what ever mag and nothing will happen to your POI.

 

What you will find is that your wobble will be magnified by what ever mag you change to.

 

The only way the change of mag has an effect on POI is when you change distance from your zero range, i.e zero on x10 at 25 metres then change to x4 or 6 for night time shooting and shoot at various ranges other than your zero range.

 

A change in mag (higher) means than your mildot hold over and under points become larger and a change in mag (lower) means that your points become smaller, i.e

 

Zero at 25m x10

 

Shoot at a target at 35 metres on x10 and you may have to hold over 1 1/4 mildots

 

Change to x4 and you may only have to hold over 1/4 of a mildot

 

Change to x16 and you may need to hold over 1 3/4.

 

Hope this all makes sense buddy.

 

Si

 

Top notch info as usual mate!!

 

Darryl

[Daz 7 563]

I use a Falcon Menace FFP 4- 14 x 44, And it doesn't change my POI whatever mag i use, It can be 10x 12x 14 x or 8x as the Reticle Increases or Decrease's with the Chosen Magnification.

But i Tend now to stick to 12x, As its also ideal for HFT, And all my Zero aim points stay the same through out the Mag range. :thumbs: .

 

regards Daz.