A comparison:
I only bring this us as a comparison. I fully expect to be Flamed for this but here goes. I have been shooting some IR 50/50 rimfire for the past year or so. 250's are occasional or at least, a small handfull, one can tell that by loking at the results. Many of the folks who compete shoot both 6.5X and unlimited Magnification. Often scores are about the same. In my case, my Sporter scores are often better than my Big Scope scores.
Some of it has to do with conditions, Sporter is shot first, before the other classes are shot and usually conditions are softer. The Rimfire game also shoots all 25 record shots at one setting so that facilitates getting Sporter done first.
I am guseeing the reason for the higher participation of 6X in Rimfire is the foremat, the agging of them with the 10.5 and 13.5 for three gun and it's an oportunity to shoot more. My conclusion is things need to change in Centerfire to facilitate more participation. I have spoken against it forcefully in the past but after experiencing another Sport's way of doing things, I have changed my thinking. The targets are scaled down for the 50 YD situation so the targets are no easier to see with 6X than in Centerfire.
I have never understood the issue of folks not being able to see with a 6X scope. If the 6X scopes are adjustd properly, they are sharper than most of the 36's. One doesn't see much Mirage with a 6X scope so that tends to make the picture sharper more of the time. Perhaps those who say they see a blurry picture don't have their scopes adjusted properly. I find that it takes a bit of work to keep them adjusted as sharp as they can be. In my opinion, the" rules" of adjusting scopes have to me modified some when dealing with 6X scopes if one wants to see through them clearly.
