I'm looking to put a scope on a rifle for KD, but I've reached a conundrum. Spend a few more $$ and get an adjustable objective, or stay with a fixed parallax. is it really that big of an issue? I haven't taken a rifle (scoped or open sights) past 200yds, so I figured I'd ask the masses that might now.
thanks!
What power scopes are you looking at?
4-12 vortex diamondbacks.
Unless there was a reason I could not use an adjustable objective it's a feature I consider almost essential. Parallax errors are complicated and often poorly understood, so I'll try to simplify. In a fixed parallax scope the lens system is focused at one distance, often 100 yards. At any other distance the scope will be slightly out of focus, and can induce an error where the crosshairs appear to be centered but due to the parallax error are actually not centered. This error is caused by the focal plane of the objective lens and the focal plane of the ocular lens being in different planes. In practical terms this error is fairly minor if your actual distance is MORE than the focal distance of the scope, but quickly becomes very significant if you use the scope at distances closer than the scopes focal distance. If you use a 100 yard fixed focus scope at 100-600+ yards the error is fairly minor, but does increase as you move further back. If you ever want to use such a scope at closer distance the parallax error increases dramatically the closer you get. To put this in concrete terms maximum parallax error at 600 yards is around 1 MOA for a 100 yard fixed scope. At 25 yards, however, parallax error could be as much as 4-6 MOA.
There are a few things you can do to mitigate this error, the primary one being perfectly consistent head position. Having said that, if given the choice an adjustable objective (used correctly - that's not always as simple as it sounds) is always worth it to me.
This issue can get very complicated very quickly so if you have questions please don't hesitate to ask. Or just get the adjustable objective and learn how to use it correctly. :)
thanks! I've used AO and fixed from 25-100yds. the AO worked better at 25 (for me). but these were known fixed distances. I'm looking at putting a scope on my m1a for a full distance appleseed (known), but not sure if the AO is really that much more. at 400yds, I'd be looking at potentially a 4" aiming error if I understand you correctly?
but if I don't adjust it and move to say the 200yd line, the error is compounded more? or would I have to be under 100yds to see that?
If we're using a 100 yard fixed parallax scope there should be no parallax at 100 yards. Note I say "should" as these settings are never perfect. As you move to 200 yards parallax error can begin to creep in (its insignificant at that distance but mathematically it's there) and will increase linearly as you move further back to 300 and 400 yards and beyond.
The CMP allows scopes in EIC matches this year on service rifles up to 4.5x and very few of those scopes have an adjustable objective so I've been shooting with a 100 yard fixed focus scope all year. These matches are shot at 200, 300, and 600 yards and I've not had any troubles i would attribute to parallax, so it's not something I would concern myself with for KD shooting. Moving up close is a different story, though, as parallax errors become very significant at 25 yards and absurd (like 16 MOA) at ranges like 10 yards. Nobody is likely to shoot much at ten yards but it's a common distance for dry fire practice and can give you fits when using an electronic trainer.
ok, so that would explain why using a standard rifle scope at 25 gave me fits compared to an AO at 25yds.
thanks for the input Agrivere!
What kind of rifle is the scope going on?
I have an optic on my Ruger 10/22. Nikon Prostaff Rimfire, parallax set at 50 yards. Absolutely zero issues shooting 25M AQT.
As Agrivere stated, NRA HP is limited to a max of a 4.5X. Lots of people were worried about "parallax" truly it is not an issue (this is shooting at 200/300 and 600 yards). I have a Vortex Viper PST 1x4 with the TMCQ turrets. I surely cannot shoot well enough to discern any parallax error at 600 yards. That is on my service rifle, AR-15. I've been able to place 1.5 MOA groups in slow prone at 600 with that scope.
On my Long Range rifle, AR-10, that has a VORTEX Viper PST as well, 50 MM obj, and I think it is a 6x18X. That has parallax adjustments available. Scott mentioned "getting on the rifle repeatedly the same way every time", if I neglect to adjust for parallax with that rifle, shooting "supported" prone, I can see an error *at distance*, especially if I don't get on the rifle correctly. Non-Traditional shooting positions like kneeling with barricade support, if I neglect to adjust the parallax knob....who knows. Heck the position is wobbly enough as it is.
Hope the above helps. Kinda interested to see what rifle you were contemplating attaching the scope to.
Whatever you choose, spend as much $$ as you can on a decent optic. Clear glass, non fogging are essentials for me. Reticle is important as well. Just as important as a reputable optic would be a reputable mounting system. That is just as, if not more important as the optic.
More magnification, is not a good thing. Heck, most hunters I know that do the rifle thing love that 50MM obj, makes sense....lets in more light. But having it set at 24X for a 100 yard shot is not a smart choice.
Took me a bit (prior to my Appleseed first experience) to understand that more magnification is not a good thing. As stated, for target shooting I use a 4X magnifcation. Works awesome.
LR shooting, I'll use the MAX magnification (18X) to find the target at say distances of 800+/- yards. If I have time (normally do) I will turn the magnification down to say 8X/9X to make the shot. That is what those fancy "throw levers" are for.
Lastly, since I brought up hunting. For SLUG guns and Muzzleloaders, I would make damn sure that the mount (as mentioned above) is solid, and also the optic is RATED for SLUGS or ML's. I've seen those rifles beat the reticles into submission from recoil on substandard optics. They usually are Tasco's, Bushnells, etc. Those HI $$ optics LOL. My rule of thumb on optics, if WALMART is selling it....it is likely not in my safe *EDIT...think they may sell the Nikon Prostaff on my rimfire, got that one at Dicks*.
Leupold and Vortex is pretty much all I have on my rifles. If I could afford more I would go for Night Force!
R/
R/
Chris
Not related to KD shooting but an experience with AO: Moved a couple of the family .22s (much used as loaners) to AO optics to improve close in focus. The primary users have loved them and the beneficiaries of the loaners are pleased. I now look for that feature in a scope. Mine were just Simmons 3-9s.
I agree with both Agrivere and Chris, parallax adjustment generally isn't a big deal but it's nice to have for centerfire optics beyond 3-9 power. I go out of my way to have it on rimfire rifles, but that's me.
However, I think magnification is application-dependent. 3-9 , 2.5-10, and 4-12 or 4-16 are all fine for general shooting in my experience. My .223 bolt gun's 6-24x is a little much, but it's also geared toward a couple of specific things I would like to try down the road.
Quote from: navybowhunter on October 20, 2016, 08:25:35 AM
On my Long Range rifle, AR-10, that has a VORTEX Viper PST as well, 50 MM obj, and I think it is a 6x18X. That has parallax adjustments available.
I am pretty sure we have the same scope, it's their 6-24x50mm right?
Scope is going on a springfield m1a loaded. I'm looking at the vortex diamondback 4-12. I understand about more/less magnification, having said that, I typically shoot aqt's at 6x....that's the lowest power my scope on my 10/22 will go, but I find it ok. lot of wobble off-hand, but I can make peace with it and keep it in the upper 40's for stages 1 and 2 (shoot both offhand). really it's more a product of me than the magnification.
I think adjustable focus is pretty important for KD. Not essential, but very nice. Keeps you from getting a headache looking through the scope and lets you spot splashes if nothing else.
Exposed turrets are nice too if you can swing them. For KD, I would go with something like a SWFA SS fixed 6x or 10x with rear adjustable focus, exposed turrets and a ranging reticle. I'd rather sacrifice adjustable power than the other features.
Quote from: cwcdl79 on October 19, 2016, 10:58:54 AM
I'm looking to put a scope on a rifle for KD, but I've reached a conundrum. Spend a few more $$ and get an adjustable objective, or stay with a fixed parallax. is it really that big of an issue? I haven't taken a rifle (scoped or open sights) past 200yds, so I figured I'd ask the masses that might now.
thanks!
You can pay attention to the 'sight alignment' i.e. make sure the scope is visually centered in the dark area surrounding it. It's a good tool to get consistent head placement and it makes most parallax issues irrelevant.
The problem comes when u place your head where it should be, open your eyes, and 'the sights are not aligned'. For me, the scope is usually too high. You may have to look for the different scope mount, play with different ring sizes, chick raises, etc etc.
Alternatively, you can get a scope with an AO and 'cheat' the cheek weld. Personally, I strongly recommend getting the scope installed properly regardless if it has AO or not.
We teach turkey neck and cheek weld for a reason.