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POI changes with zoom????

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Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/25/2011 at 19:52
shooter4 View Drop Down
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Here is something I have not heard before - is it possible Point Of Impact changes with changes in magnification??
 
I was reading the new issue of rifle firepower magazine and someone mentions this there......hmmmm
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/25/2011 at 23:25
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For the most part, IMHO, what changes is the point of aim. Esp. in a second focal plane scope, this is because the reticle covers much more of the target at lower powers than it does at higher powers. 
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/25/2011 at 23:32
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A descent quality scope should not have that issue.  A cheaper one will be more likely.
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/26/2011 at 08:16
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can occur with sfp scopes. In order for this not to occur the erector system would have to be a perfect mechanical assembly that repeated itself without error each time it moved. Since it doesn't a random variable or error can be introduced each time it is racked in and out. Most scopes used in the US are for hunters who don't shoot very much, and if the scope passes the 3 shot sight in it's good to go.  Also the box text of scope for a hunter is placing an empty box at 200 yds and if they hit it on the first shot its also good to go.
While the reticle covers more of the target on higher powers, the lack of reticle size increase allows for bisection of the target in a more precise manner, which leads to a predicable error. POI change  due to power increase/decease is random----it is not predictable. A big difference. Most higher quality scopes will probably due this less, NF,Zeiss etc. and if the degree of precision in the target is not necessary would probably not be observed.
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/26/2011 at 09:36
shooter4 View Drop Down
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Thanks for the advice.
 
Im a bit puzzled by this. I have a Zeiss Conquest on one of my 1022´s and while testing it the other day I found it was near 4" off target at 45yds, 4" low and 2" to the left.  So I dialed as appropriate...or so I thought but the impact did not change........Hmmmmmm.
 
I dialed in some more (about 3 clicks more or so up and 3 right) and it was still off target - by almost the same. So next I dialled in about 5 clicks up and then it was better but still 0.5" low and 0.5" left.
 
I found this strange as usually it responds right to the clicks. Not quite so now. And yes, I was always using the same Lapua ammo.
 
So I was wondering if the adjustments are faulty all of a sudden, or its me getting too old, or if its connected to the fact that I DID chance the magnification in between shots, went from 9x down to 5x????
 
What ya think?  I guess the Conquest is a fine product and it has not had any accidents.


Edited by shooter4 - November/26/2011 at 09:37
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/26/2011 at 10:02
Urimaginaryfrnd View Drop Down
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I think new 22's suck they seem to shoot all over the place and I remember the ones from years ago being a hell of a lot more accurate.  There are lots of variables here. First suspect is the rings and base make sure they are secure and of good quality. From there start testing the scope shoot a box  on a target to see how well the adustments of the knobs is working.  X ring up 4 inches right 4 inches down 4 inches left 4 inches and look at the target. Do this at different magnifications to try to figure out what is going on.  If you suspect something has gone wrong with the scope you can send it to Zeiss to be tested and repaired.  You can also put a different scope on the rifle and try to see if you still have the same problem or try that on a rifle you know is super acccurate.  I would be a lot more likely to eliminate the rifle as the culprit if it was a 17 hmr or a centerfire that was known to shoot a tight group.  22 ammo for the most part sucks these days years ago it was better quality or the barrels were not sure which.
*
Note a 1/4 moa scope moves 1/4 in at 100 per click but at 50 yds it only moves 1/8 in per click and at 200 it mives 1/2 in per click at 300 it moves 3/4 in per click.


Edited by Urimaginaryfrnd - November/26/2011 at 10:16
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/26/2011 at 10:02
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Have you checked your mounts? I know every time I think my 30 year old tasco has finally gone tits up on my .22...It has been that the rings have moved on the built-in dove-tail on the receiver. (I really want a new scope for that rifle, but the wife won't let me until it is dead.) 
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/26/2011 at 10:06
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Refer to Rule #1 ...
 
 
Rule #1:  What Women Don't Know Often Wont Hurt Them.
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/26/2011 at 10:12
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The unfortunate thing about that plan is my wife seems to be a bit more observant than most...Esp. when it concerns the guns she enjoys. The .45 is her favorite, but the 22 is a close second...
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/26/2011 at 10:19
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Well you failed to mention that it was HER GUN!!! its time to buy one of your own that one is Her's now.
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/26/2011 at 10:24
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I did see a Savage MKII at WallyWorld...
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/26/2011 at 10:55
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I have the MKII Savage with the thumb hole stock the mag only holds 5 rounds and the 10 round mags are about $20. I had a marlin bolt that was more accurate than the Savage and traded it thinking it was not accurate enough. Ive been full circle with 22s in the last three years.  Think if I was going to buy another one it would be a Ruger 10-22 they made one with a longer than average barrel that I like.  Here lately I had been wanting a 22mag and stumbled across a Marlin levermatic model 57M  built 1959 --- Coolit came home with me. I used to have a Marlin 39A lever action now that was a 22 that would shoot.   Paul took the 22mag to the farm and says it shoots real well, I knew it would it was build when people cared about what they were making.

Edited by Urimaginaryfrnd - November/26/2011 at 10:57
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