Tall target test

I've used airguns to evaluate scopes before installing them on powder burners. Both tall target tests and box tests. At 50 yards it's just half the size it would be at 100. Measurements are bound to be a little less accurate because the error is halved as well, so a small error may be completely hidden and a discernible error could be somewhat worse if tested at longer distances. As a prequel to longer distance testing I think it's very worthwhile.

GsT
 
I have set up a large cardboard to do that very thing. Just haven't gotten a good day to do the test. There is however, an decent video on how its done and a formula that can be used for shorter or longer distances.

mike
That's is a very informative video for sure. I wonder if the calculations hold true at 50yd and using mill dot in stead of MOA!! If it does I will definitely use that!!
 
Well, the formula seems to work, while I haven't hadda chance to actually perform the test, I have marked up my large cardboard target with all of the incremental 'distances' that I have set, starting at the 50-yard mark.
I have set up my board having the 50-yard start at the bottom and measured per the formula for each increment of 25 yards and marked that above the 50-yard mark in a straight line (in other words, I have premeasured the anticipated POI instead of measuring while out there). I plan on using a plumb bob string to assure level when I finally get to try it out.
There are actually 2 formulas, one for MOA, which the vid shows, the other for MRAD. It's a multiplier of .03599 for MRAD.

mike
 
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I have used close(and far) tall target test for years now. Every time I mount a scope on a rifle(or if there is a problem), I use a quick close tall target test to help verify level/anti-cant device, scope reticle markings, and click values, as well as, info from ballistic apps.
However, everything must be measured and leveled correctly to ensure proper results.
Due to the trajectory of relatively slow moving airgun projectiles(sub-sonic), I have found airgun shooting at longer distances(50 to 250 yards, depending on power level) has more in common with long distance powder-burner shooting(400 to 1000 yards, depending on caliber) than people realize.
 
Well, the formula seems to work, while I haven't hadda chance to actually perform the test, I have marked up my large cardboard target with all of the incremental 'distances' that I have set, starting at the 50-yard mark.
I have set up my board having the 50-yard start at the bottom and measured per the formula for each increment of 25 yards and marked that above the 50-yard mark in a straight line (in other words, I have premeasured the anticipated POI instead of measuring while out there). I plan on using a plumb bob string to assure level when I finally get to try it out.
There are actually 2 formulas, one for MOA, which the vid shows, the other for MRAD. It's a multiplier of .03599 for MRAD.

mike
I appreciate the information Mike.I figured there had to be a different multiply for MRAD.👍🏻
 
Tall target tests are a great way to test a scope… they’re also a great way to get some erroneous information. It’s easy to blame the scope for human error in these types of tests.

You can’t measure the 50 yards with a LRF… you need EXACTLY 50 yards, so use a wheel or highly accurate laser device for construction.

You MUST have the rifle level, shoot across level ground, and use a plumb-bob when setting up the target to ensure that the vertical tracking is true to the y-axis.

I have not done a TT with an airgun… but I have done several, as well as a ton of lr field shooting, with very accurate .22lrs. There’s no better way to put an optic through its paces than running a brick of .22 through it and spinning the turrets for nearly every shot… I’d imagine the same would be true for a very accurate PCP.