I know that parallax is one of today's favourite excuses for bad shooting, but...when it comes right down to it, that's what it is: an excuse. Parallax happens when you have the image and the crosshairs on two different planes within the scope; as you move your head away from a perfectly centered position, you are essentially looking "around" the crosshair at the image, or vice versa. As you move your head, you will see the crosshairs apparently moving on the target image; the further away your head moves from the perfectly centered position, the further the crosshairs move on the image.
Frankly, this can be a great aid to training and maintaining good form. You should only fire if your head is centered behind the scope, giving you a perfectly round field of view with an equal black border all the way around. If you see that every time...your head is in the same correct position...and parallax ceases to exist. Of course, it's impossible to maintain this perfectly, but training to replicate it as closely as possible at all times is excellent practice; it's just another part of the consistency that good shooting demands.
Anybody who doesn't believe this, or who likes to blame parallax for their misses, should lock their rifle into a solid shooting rest/vice, put their head into shooting position and place the crosshairs on a target at 25 or 50 yards. Do this with a centerfire scope that has parallax fixed at 100 or 150 yards as most do; or if your scope has adjustable parallax, set it for 100 yards. Now move your head left, right, up, down and observe how much the crosshairs appear to move on the target. If your target has a grid pattern, it will be easy to see how much the crosshairs move and how much the maximum error caused by parallax will be. You're in for a shock; it varies from scope to scope and from one magnification to another and at different target distances...but it's not nearly as extreme as many seem to think.
And to get that maximum error, your head will need to be so far off centre that you will be looking at a crescent-shape field of view that barely allows you to see the target. Nobody shoots like that; if you limit your head movement to the small amount that still lets you see the target properly, your potential parallax error is even less. As long as you can see the target clearly, you're golden.
Obviously, if your goal is ultimate precision at any cost then adjustable parallax is a nice feature that will make a small improvement to your shooting, and one you should use. But if your goal with rimfire shooting is simply to practice and get as much trigger time as possible to improve your overall shooting form and consistency...eliminating parallax by keeping your melon properly and consistently placed is actually a training aid.
Frankly, this can be a great aid to training and maintaining good form. You should only fire if your head is centered behind the scope, giving you a perfectly round field of view with an equal black border all the way around. If you see that every time...your head is in the same correct position...and parallax ceases to exist. Of course, it's impossible to maintain this perfectly, but training to replicate it as closely as possible at all times is excellent practice; it's just another part of the consistency that good shooting demands.
Anybody who doesn't believe this, or who likes to blame parallax for their misses, should lock their rifle into a solid shooting rest/vice, put their head into shooting position and place the crosshairs on a target at 25 or 50 yards. Do this with a centerfire scope that has parallax fixed at 100 or 150 yards as most do; or if your scope has adjustable parallax, set it for 100 yards. Now move your head left, right, up, down and observe how much the crosshairs appear to move on the target. If your target has a grid pattern, it will be easy to see how much the crosshairs move and how much the maximum error caused by parallax will be. You're in for a shock; it varies from scope to scope and from one magnification to another and at different target distances...but it's not nearly as extreme as many seem to think.
And to get that maximum error, your head will need to be so far off centre that you will be looking at a crescent-shape field of view that barely allows you to see the target. Nobody shoots like that; if you limit your head movement to the small amount that still lets you see the target properly, your potential parallax error is even less. As long as you can see the target clearly, you're golden.
Obviously, if your goal is ultimate precision at any cost then adjustable parallax is a nice feature that will make a small improvement to your shooting, and one you should use. But if your goal with rimfire shooting is simply to practice and get as much trigger time as possible to improve your overall shooting form and consistency...eliminating parallax by keeping your melon properly and consistently placed is actually a training aid.
