POA/POI and focal plane problems

ScREWtop

Member
Joined
Dec 8, 2003
Messages
13
Location
NZ
Hi,

I am not sure if any of you experienced this before but this happened to me a few times before.

Line up a target, dial in, pull the tigger and bang on. Spotter calls out another 5 targets the size of 2" square blocks and they get pulverised, just as easy.

Very precise shooting and I'm very pleased with myself.

Then the sun pulls out of the clouds and suddenly I am not hitting the targets anymore. I checked my water bubble and my gun was canted. I straighten it and the target disappear out of my focal plane.

The only way I could see the target was to cant and my bullets are going over at 1 O'clock high.

Same thing happened a couple of weeks ago but the opposite. I was shooting well when the sun was bright. As soon as the light condition changed, I had to fiddle with the knobs. And that makes it worse....

I am using a Premier Reticle 20x50x50mm and the same thing happens at 20x or 50x magnification. I tried cranking it down to 20x and still can't see the target unless canted.

Of cos I could reset myself, reposition the rifle and it'll work but I can't figure out why light would affect it so much.

Any help grately appreciated.
 

Dave King

Well-Known Member
Joined
May 3, 2001
Messages
2,366
I'm a little confused but the description(s) but I'll offer something.

When you mention you discovered the rifle was canted and you straightened it up the image went "out of the focal plane" (I read as "the image went away, as in disappeared"). Rotating the rifle to remove the cant and having the image "go away" sounds like an astigmatism abberation thing... I'm not a rocket scientist not optical engineer so this is a stab-in-the-dark. You can do a search in the web for astigmatism abberation riflescope or some such and find more info. "Sun up" and "sun down" are often discussed in long range shooting... sun up--- bullet up, sun down---bullet down as I recall... could be garbage but more stuff to look up.

Maybe some optics fella(s) will chime in. Call the folks at Premier and chat with them if they have a few minutes...
 

ScREWtop

Member
Joined
Dec 8, 2003
Messages
13
Location
NZ
Dave, how did you know I had astigmatism!!??

Yes, I wear contact lens and I have very high astigmatism. When I try to straighten the rifle the target is gone! Gone I mean outside what I could see in the scope, and I have to move my scope around to find the target again. But this happens when the light condition or something change. Maybe my eye ball moved


But say like I am shooting 4, 5, 6 targets and I remain in the same spot same target same everything, and the light condition change, suddenly, I am missing the target on 7, 8, and 9.

The targets don't just disappear but by missing I meant I open my bolt, recock my rifle and I see the target but I won't hit it dead center. I would be on the white or something.

I look at my rifle's bubble and its canted. So I straighten my rifle but the target is no longer in the scope. To get the target back into the scope, I would have to re-set myself all over. Maybe move the bipod etc.

Whats going on here? help anyone?

Thanks.
 

Trending threads

Recent Posts

Nightforce has great tracking capabilities, they are rugged, a bunch of elevation, holds zero forever, and reticles are designed for long range shooting. So if you are looking to shoot long distances constantly, then you need a scope that can take the abuse. -- gilmillan1


Culture Of Excellence At Nightforce Optics
By Len Backus

A high level of quality both in production and in service. Read More


Nightforce is such a solid combo of reticle, available elevation, glass that is good enough to shoot at the longest range you can dial. Nightforce has bullet proof construction that can handle the incidental horse rolling or some other rodeo action. -- bigngreen


Nightforce ATACR Scope Review
By Jeff Brozovich

The new NightForce ATACR is for sure a top choice for any long range shooter. Read More


The total package. Nightforce is the best I have used as far as turret feel and solid detents. I have never had one that didn't track right on and always return to zero. Nightforce NXS is the best value for everything I need. -- Broz


Nightforce Velocity 1000 Reticle Review
By Scott Shreve

I think Nightforce knocked it outta the park with this reticle! Read More

NightForce


Top