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Just saw Hugh Birnbaum's article in the October Shooting Times. The bottom line of his article is that he used a 1.5-6x variable and a 35x target scope on the same rifle, a .223 Remington Varmint Special, and shot groups with it using the variable at 1.5 and 6 powers, and then using the 35x target scope. His groups averaged .96" at 1.5x, .75" at 6x, and .708" with the 35X. His comment was that the 6x and 35x groups were essentially no different. This is, of course, just a single shooter and a single gun and results might or might not be duplicated with a broader test. But I suspect that, in terms of 100 yard groups, magnification greater than about 6x is reaching the point of rapidly diminishing returns. I'm always amused at some hunters (almost always younger ones) who mount their hunting rifles with scopes like 6-18's and worse. There's little to be gained in a hunting rifle with that kind of magnification other than weight and expense, both at the loss of a wide field for quick target acquisition. | ||
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For load development, I use a 36x Leupold Target scope, then switch to a hunting scope after finding the best load. For hunting, I use 4x scopes on most rifles, with a few having 6x scopes, but NO variables, except for the new VX-7 I just bought, a 1.5-6x. If Leupold would have made a fixed power scope with the good glass of the VX-7, I would have bought a fixed power. The VX-7 will be set at 4x and left there...  Oh, one more thing, in deference to what Hugh writes, Benchrest competitors all use scopes with powers in the 30's and 40's, for a very good reason. They get smaller groups using high powered scopes. Don | |||
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I bet the BR shooters will be turning in their high powered scopes for straight 6s any day now Reloader | |||
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There is no doubt that shooting your best group at a 100 yds is easier with 9x than with 6x. With the 9x magnification you can divide the 1-inch bull on the target in 4 quadrants and so position the crosshairs smack in the centre, whereas the 6x magnification would cover the bull in its entirety and thus positioning is compromised. Just my observation as seen through my eyes. Warrior. | |||
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There's no doubt that the .032" difference is important to a benchrest shooter, however, I think you miss the point of Birnbaum's article: High magnification (relative to the distance of the target) does little to improve aiming accuracy. Relative to a deer, an elk, or a wildebeast, there is no measurable difference in using a scope of modest power as compared to a scope of high magnification.
I agree that how the reticle appears against the target can be very important. As an example, I have reduced the white bull on a standard benchrest target so that the dot on one of my scopes perfectly fits it. This has improved my groups with this gun/scope by perhaps an average of .1". However, this has more to do with the appearance of the reticle against the target than with the actual magnification. I'll redily agree that greater magnification makes precision aiming easier; it's just that for 100 yard groups, greater magnification doesn't result in proportionally better aiming. I hunted Namibia earlier this year in the dry southern area where the terrain is very open and shots tend to be long. As a result, I used my 3-9 variable almost always set to 9x. However, when we were looking for zebras, the situation was such that we might jump them closeby, so I had rolled the magnification back to about 4x. As it turns out, when the zebras were spotted, the best stallion was out in the clear between 275 and 300 yards. I was able to find a good rest, but completely forgot about my scope magnification. Didn't make a bit of difference. It was a one-shot kill, and it was only after we returned from the field that I noticed my scope was set at only 4x. Like DMB's comments above indicate, there's not much in game hunting that a 4x won't do. Varmints and targets are, of course, a different story. | |||
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Using the correct target for the application also figures prominently. With a target that suits the magnification and reticle, you can certainly shoot impressive groups with a 1.5 or 2x scope at 100 yards. But with a poorly-matched target-scope-reticle combination, those groups will grow considerably at low-powered settings. Bobby Μολὼν λαβέ The most important thing in life is not what we do but how and why we do it. - Nana Mouskouri | |||
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Varmints and targets are a different story. Fot them I have variables, and fixed powers much higher than 4x. The thing that got me off of using variables for Deer hunting is for exactly what you describe with the Zebra shot in Africa. I found that when using a 3-9 variable, I would set the power to some intermediate setting, like, 4x to 6x and leave it there. When deer came along, there was no thought of changing the power, I shot the Deer. I said to myself, why do I need variables on Deer rifles? So, now I have all fixed 4x and 6x scopes on those rifles. Besides, for hunting the swamps up here, anything much over 4x is useless, actually a hindrance. I gotta say though, for load developing, that 36x scope lets me pick a small spot on the 100 yard target very well. Maybe you young guys can shoot well with 4x's at 100, but I need all the help I can get.. Don | |||
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Don: Virtually all of my "serious" hunting rifles carry variables, typically in the 3-9 range. I use them at 9x, of course, for load development, much like you use your high power target scope. I frequently hunt with them on a lower power, although there are some occasions when the maximum power is not a drawback. I certainly can't fault anyone for using the highest power available for load develpoment -- it has advantages beyond precision in aiming, like being able to see the bullet holes and more precisely calling your "mistakes" (when your trigger breaks with the reticle off-center). But once the load is developed, as Birnbaum observes, there's so little difference in modest power and high power as to make magnification irrelevant to hundred yard shooting. By the way, no matter how well a variable is made, it will always be a little heavier, a little bigger, a little more complex, a little more prone to moisture infiltration, a little more likely to fail to hold its zero, and a little more expensive than a fixed power scope. There's a lot to be said for the "old-fashioned" 3, 4, and 6 power fixed hunting scopes. | |||
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One of the first things your PH will tell you entering the bush is to cranck your scope to the lowest mag. Also it is a big difference in your field of view between thw lowest and highest option | |||
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It's really personal preference when it comes down to it. I will say that I personally shoot smaller groups with higher mag scopes. It's just flat out easier. For instance, when target shooting, I can shoot much smaller groups at 200+ with the scope set at 18-20x than I can with it set a 6x. I just can't make out the target that well with 6x as I can with 18x, therefore my aiming point is not as precise at the lower mag and the groups open. I also love to zoom in on game when I'm hunting. For instance, last season when I took my bull in CO, I carried my rifle on 4.5x. Once we glassed the herd, spotted a shooter, made the stalk, and set up on the sticks, the guide gave me a range of 325 to the big bull and I cranked it to 14X waited for the cows to clear and squeezed off the shot. I've had that same situation arise in the past. My personal prefernce is varibles with 3-6X on the low end and 12-20X on the high end. I carry on the low power and zoom in when needed. I can also tell far more about a bucks head gear at 20X than I can with my binos or when my scope is at low mag. I cartainly don't care to carry a set of binos, LRF, spotter, and my rifle when I hunt. Others may, but I prefer to leave the spotter in the truck. Reloader | |||
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I basically did the same thing done in the article. Only I used an accurate 22LR rifle at 50 yards, Did various mags from 3x to 24x using two different scopes on same rifle with same ammo. 22's are cheap enough to shoot lots of groups and average out the results usefully. Results aren't much different. Okay so then I looked at this. How much area is covered by the crosshairs. Most duplex reticules are 2 moa wide in the middle. So the center covers roughly a 2moa by 2moa area at 100 yards. This should then be divided by the magnification. For instance 10x covers 1/5th of an inch on the target. 20x lets the crosshairs only cover 1/10th of an inch. So the most your aiming accuracy improves going from 10x to 20x is 1/10th of an inch. Your 1 inch groups at most shrink to .9 inches at one hundred yards. At only 5x the crosshairs cover 4/10ths of an inch. So going from 5x to 20x at most would improve aiming accuracy 3/10th's of an inch. Enough to matter to target shooters. Maybe enough to start mattering to varminters at 300 yards and more. On larger game, it just aint a factor to worry with. When I averaged my groups with the 22LR it followed the reasoning above almost exactly for the different powers of magnification. I have shot 3/4 inch groups with 6x at 100 yards using a centerfire and appropriate target for the 6x reticule. I have shot less with more magnification on that rifle. But the difference in 1/2 inch versus 3/4 inch on anything other than small varmints or targets is pretty meaningless. A fixed 6x rides atop that rifle now. | |||
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I have been using the 6X magnification on my scopes for years to shoot groups with. I've come up with a homemade target that the crosshairs exactly cover at 6X. I get awesome groups using this system. Elite Archery and High Country dealer. | |||
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I would agree with HB's findings, when it comes to shooting paper, even as far as 300 yards. However, while a higher power scope might not enable you to shoot any better, it does let you see better. So, depending on the game you are hunting, and the range you are shooting, a higher power variable scope may have some merit. DOUBLE RIFLE SHOOTERS SOCIETY | |||
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Good to see it quantified. Being familiar through always seeing the same sight picture is worth more to me. | |||
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With this combination, he was NOT testing the scopoes, but the rifle. I bet if he had shot all the respective groups with one scope he would have gotten the exact same results. To really test this theory, one needs to use a real bench rest rifle that shoots in the 00s. As for hunting, as against varmint shooting, I would prefer a lower power scope to any one with a higher power. | |||
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In OZ here we have a pro shooter that does most of the test shooting for a local mag. He has stated that he shoots a smaller group with a lower power. This may have been only with a .22rf at 50 yards, I can't find the article now. (naturally) But I just sent them an E-mail to do an article about it. Just don't hold your breath. As for 6X for everything, I fell for that idea for a while. Then I realised that trying to hit a fox at 200 yards would be better with more power, and walking through thick bush with 6x was not as handy as a lower power. It seems some people have trouble adjusting their power ring to suit the circumstances. But at least they could put their varible at 6x if they can't decide.  | |||
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Well there are two factors here. One is the accuracy potential of the rifle. The other is the aiming accuracy. There is simply no way around the fact that shooting with higher magnification reduces aiming error. Simple trigonometry will tell you how much that can amount to. The rifle is harder to define. But for instance, maybe it is a .700 inch rifle. The difference otherwise is aiming error. You have more at lower powers. Less at higher powers. I have done this with an accurate .22 using many groups. The difference between any two magnification levels was basically the difference in aiming accuracy from magnification. There is really no mystery on this. | |||
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Very well put!! I just finished reading the article in question. My conclusion is that he has a rifle which is only capable of about 3/4" groups. Or, perhaps, HE is only capable of 3/4" groups. Either way, by the time he gets up to 6-X, he can see well enough to get groups as small as he and the rifle are capable of. Obviously at that time, there is no point in using more magnification. However, with a rifle and shooter capable of shooting groups in the 0.0 MOA range, the better they can see, the better they can shoot. On hot, muggy, days the mirage may limit how high they want to go in power, but even then I don't see many benchresters throwing away their 30 m/m tubed 45-X Leupolds....or even switching down to as low as 24-X for that day. My country gal's just a moonshiner's daughter, but I love her still. | |||
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In my limited amount of using different powers of scopes on different rifles from 17HMR to 300WinMag, I would have to say that the variables in 3x9 are about the top of the list for covering the bases. That's not to say there isn't a need for the higher powers(14-24)......GOD knows I use a bunch of them for the varminters!! But I figured out years ago that less magnification seems to make one a better shooter from the bench when testing firearms for potential! (NOT BR stuff.......for that I use 24x straight powered glass or 16x straights just for the fact that the target being aimed at is consistent and never varies unlike the hunting or varminting applications!!) I always try to steer young shooters to the lower powered scopes instead of the behemoth scopes. Get them shooting the 3, 4, 6, 9 power stuff and having good "bench practices" and then if they want to, move up to the higher powers! Not only do the higher powers magnify the target, they magnify the effects of breathing, heartbeat and mirage!! Get good with your rifle at the lowere magnification before moving up to the "mega-powers"! I also like the Bushnell Holosights with the 1MOA dots!! Using them to shoot sub MOA groups at 100, 200, 300 yards can teach a lot about "gun control" or shooting regimen!! For all practical purposes, those things suffice for deer, or varmints or whatever else you may think of up to 100 yards or more! GHD Groundhog Devastation(GHD) | |||
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 Warrior | |||
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I have shot my best groups with a Nightforce NPR-2 reticle 3.5X15 set on 15 power... These 300 yars groups were shot on 15 power... I don't believe that I can shoot a group this small on 6 power   _____________________________________________________ A 9mm may expand to a larger diameter, but a 45 ain't going to shrink Men occasionally stumble over the truth, but most of them pick themselves up and hurry off as if nothing had happened. - Winston Churchill | |||
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The Accurate Reloading Forums THE ACCURATE RELOADING.COM FORUMS Guns, Politics, Gunsmithing & Reloading Optics Magnification and Group size
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