Scope Reticle Accuracy

[magtech]

How far off should a ffp scope reticle be at a 20 moa holdover. Mine is about a 1/2" off @ 20 moa. It becomes fairly noticeable at 10 MOA holdover. Could this be an issue with the parralax not be setup correctly? (I had it lined up exactly at 100 on the knobs)

My test target is at 300ft measured with a tape. With MOA hash marks at every 2 moa (1 moa = 1.047"). Measured with a dial caliper.

Is it just me being me or does this happen occasionally?

Most importantly, is it normal?

 

[whatsupdoc]

Always wondered about this, are you measuring 300ft to the scope objective? and is the reticle +or- the 20moa.

 

[bigdaddydmd]

You are measuring "true MOA" on your test target. Does you scope reticle/turrets track in "true MOA" (1.047" at 100yd) or in "shooters MOA" (1.00" at 100 yd) "Also referred to as IPHY (inch per hundred yards) or SMOA"?

I remember Frank posting a thread about true MOA vs shooters MOA awhile back and he mentioned that some manufacturers build scopes in "true MOA" and some build in "shooters MOA". I will try to find the thread since I am just going off of memory. I do know that there is an acceptable percentage of + or - accuracy in tracking (turning the turrets), but I don't know if that relates to reticles also. Perhaps some one else is more knowledgeable about this issue than myself and can add in.

 

[_Windrider_]

What scope is it? As he ^^^^ said, your turrets are probably IPHY and your reticle is correct MOA. This is important to know.

 

[BOLTRIPPER]

there is a barber pole on some ranges...red/white in metric distances to the verticle, that will confirm mildot spacing when viewed at 100 meters, additionally this same pole will confirm scope tracking when run up and down.....

i can not remember the proper name for this procedure and pole.....Jhuskey here on the Hide will know for certain

 

[magtech]

It's a gen 1 PST. Nothing exotic. I just didnt know if it's worth sending in, or if i'm just wasting my time looking at this stuff.

 

[bigdaddydmd]

Looks like the Vortex Viper PST MOA reticles are true MOA reticles. I was suspecting your scope was in SMOA and you were setting your test target up in True MOA but that isn't case.

"The EBR-1 reticle is based on minute-of-angle (MOA) subtensions. MOA measurements are based on degrees and minutes: 360 degrees in a circle, 60 minutes in a degree for a total of 21,600 minutes. These angular measurements are used to estimate range and correct for bullet trajectory drop in riflescopes. 1 MOA will correspond to 1.05 inches at a 100 yard distance, 2.1 inches at 200 yards, 3.15 inches at 300 yards, and so on. "

Copy and pasted from their website for the manual for the Viper PST 4-16 with EBR-1. Not sure which reticle you use. So, either 1) the reticle is off by a certain %, 2) your distance from optic to test target is incorrect, or 3) your measurements between your test targets 2MOA hash are incorrect. We can rule out measuring with reticle set to the wrong magnification since it is a FFP instead of a SFP scope and we don't have to worry about having the magnification set to the correct power that the reticle subtends at.

Since you measured with a tape and set 2MOA hash marks with a caliper the problem is likely in your reticle. Is it worth sending in? That is up to you to decide. Have you stabilized the rifle in a vise/sled set on bullseye and dialed the 20 MOA to see if the center of the reticle tracks with your test target? I am curious to see if the turrets track in true MOA and the reticle is just off a certain percentage in size. I think the acceptable tracking percentage for that scope is 3% plus or minus, but am not 100% certain on that.

 

[_Windrider_]

Looks like the Vortex Viper PST MOA reticles are true MOA reticles. I was suspecting your scope was in SMOA and you were setting your test target up in True MOA but that isn't case.

"The EBR-1 reticle is based on minute-of-angle (MOA) subtensions. MOA measurements are based on degrees and minutes: 360 degrees in a circle, 60 minutes in a degree for a total of 21,600 minutes. These angular measurements are used to estimate range and correct for bullet trajectory drop in riflescopes. 1 MOA will correspond to 1.05 inches at a 100 yard distance, 2.1 inches at 200 yards, 3.15 inches at 300 yards, and so on. "

Copy and pasted from their website for the manual for the Viper PST 4-16 with EBR-1. Not sure which reticle you use. So, either 1) the reticle is off by a certain %, 2) your distance from optic to test target is incorrect, or 3) your measurements between your test targets 2MOA hash are incorrect. We can rule out measuring with reticle set to the wrong magnification since it is a FFP instead of a SFP scope and we don't have to worry about having the magnification set to the correct power that the reticle subtends at.

Since you measured with a tape and set 2MOA hash marks with a caliper the problem is likely in your reticle. Is it worth sending in? That is up to you to decide. Have you stabilized the rifle in a vise/sled set on bullseye and dialed the 20 MOA to see if the center of the reticle tracks with your test target? I am curious to see if the turrets track in true MOA and the reticle is just off a certain percentage in size. I think the acceptable tracking percentage for that scope is 3% plus or minus, but am not 100% certain on that.

The reticles are always true. It’s the turret that matters.

 

[Blowby]

The reticles are always true. It’s the turret that matters.

If the reticle is installed in the correct location. Just think of SFP and the distance is relevant to where the reticle is set in the tube.

 

[whatsupdoc]

So has anyone tested different manufactures scopes for reticent accuracy? I myself have tested a few of my scopes tor tracking accuracy but have never checked the reticle to see if it is calibrated correctly.

 

[Blowby]

Funny story on a scope released from the factory. Tracking was off so they set the reticle location to match the tracking error. Sent it back and it’s dead nuts now, both tracking and reticle.

 

[bigdaddydmd]

The reticles are always true. It’s the turret that matters.

I agree that it is the turrets that matter (cause I want a scope to track dammit) and I would assume a reticle is always true. If I am understanding the OP's initial post it sounds like his reticle is not "true" on his tall test target by measuring the reticle compared to a tall target marked out at 20 MOA. I am curious if the reticle location was set off just a little bit in his FFP scope like what Blowby referred too, and I am curious if his turrets track true also. The initial thought I had was he must have been off on the 100yd distance or off while laying out the tall test target as all reticles must be "true", but it is hard to argue with a 300 ft tape and a 2 MOA marked out with a caliper. I know if I was testing my scope the first thing I would double check would be distance from optic to target and layout of the 2 MOA hashmarks just to rule out operator error.

 

[magtech]

I have tried to test the turrets from my target position but its just too hard to do without a phone scope to have a constant eye on the picture... And a base thats concreted in place. When I was shooting at 1k a month ago I was shooting way high, 2+ moa. So maybe I havent trued my BC data enough... I dont know.

I only checked the reticle because I had the turret target created. I couldnt get a consistent eye position while dialing. Having a base thats concreted in would help to confirm or deny the results of the turret test. Checking the reticle out was way easier to do from my bench. Vortex wouldn't tell me anything. They just sent me the standard sent it in label... Which is nice.. Maybe I should call them, instead of email.

 

[Apnea]

@magtech I have to remind myself to check parallax when I see something I am not expecting. Some optics seem to be more sensitive in this respect than others. Since your problem seems to be a mismatch between the reticle hash marks and your measures target index marks, a parallax problem seems like it could play a role.

 

[Sig Marine]

The markings on the parallax knobs are seldom true to the yardage for every shooter or scope. Makes no difference as you set the parallax to your eyes/target not the numbers on the knob.