puzzling scope problem

haven't found the problem/solution yet, but thought I would post it here first to see if anyone guesses correctly. I even have Bruce of High Power Optics stumped, I did a crosshair elevation click test this morning and haven't heard back from Bruce on the results.

I bought a Swarovski Z5 3.5-18x44 P Sheep Hunter from Bruce. Click values are 1/4" per 100 yards.

I shoot a 7 mag with Barnes TTSX 150 grain factory ammo. I had a Z3 scope on this rifle before using the exact same ammo. My ballistics were spot on Barnes chart and iSnipe.

Yesterday I sighted in the rifle zeroing at 200 yards. It was shooting very tight groups.

From iSnipe I expected about 8 clicks for 300 yards, turns out it was 17 clicks, still shooting tight groups. 400 yards took 17 clicks and 500 yards another 17-18 clicks. Again, all tight groups once dialed in, but about twice as many clicks as ballistic charts indicated and past experience. We were expecting full range of dial (56 clicks) could get me out to 700 yards, but full range of dial with 200 yard zero was just short of 500 yards.

Range exactly accurate, ammo good and consistent, 80 degrees and 80 humidity yesterday wouldn't cause that big of variance.

Bruce had me do a elevation click test this morning. At 50 yards I got the following results...

I went max low on the turret, I then measured every 20 clicks higher.

1st 20 - 2”
2nd 20 - 2” (4” total)
3rd 20 - 2” (6” total)
4th 20 - 2.5” (8.5” total)
5th 20 - 2.5” (11” total)
6th 20 - 2.5” (13.5” total)
7th 20 - 2.5” (16” total)
8th 20 - 2.5” (18.5” total)
9th 20 - 2.5” (21” total)
10th 20 - 3” (24” total)
11th 20 - 3” (27” total)
12th 20 - 2” (29” total)
13th 20 - 2” (31” total)
14th 4 final clicks
—
Total 264 clicks

I'm not looking too much into the elevation variance, was getting pretty good parallax errors as adjusting that out made target too blurry.

I haven't heard back from Bruce, but to me 264 clicks (4.75 full rotations) is way too many for this scope. It is almost like the dial is labeled 1/4" per 100 yards, but behaving more like 1/8" per 100 yards.

We'll see what Bruce says, but any ideas?

Get out of the term "clicks" Is the turret 1/4 MOA or 1/4" per hundred yards? There is a difference.

Have you chronographed this ammo?

Is this scope designed to be mounted on a 20 MOA base?

When you tested at 50 yards, did you lock the rifle down and dial and view through the scope or did you shoot what you dialed?

So it appears by results of the test are expected. I had about a 2.5" change for every 20 clicks at 50 yards, which equals 5" at 100 yards or 5"/20 = 1/4"



1/4" PHY



I'm doing that next, it is supposed to shoot 3,000 fps. I was shooting for several different batches and it was all consistent. This is exact same ammo and rifle I used with the Z3 and my shooting results with it have always been exactly to chart and iSnipe.



Euless Guns & Ammo mounted it, so they know what they're doing.



secured rifle leadsled and view through scope at tape measure.

All my scopes "click" when I turn the turrets. They don't ring, chime, or whistle....

So they move in quarter MOA increments? Come up 2 MOA. If you have turrets as you mentioned, who gives a chit how many times they click? A turret is labeled, turn it to the number you need and don't listen to the clicks, you'll lose count. If it's capped windage and elevation adjustments, then they are not turrets, so you have to count clicks. But you said turrets.

So the tracking test shows the scope is tracking as designed.



If you input higher fps into any ballistic calculator and it the bullets is consistently impacting low then you have your MV input wrong, or your ballistic coefficient wrong, or both. But the rifle shot consistently at all ranges. Therefore you have a value input incorrectly.





Don't assume that. Any scope in the world can be mounted on a "0" MOA, a 20 MOA, 30 MOA, ect. That doesn't mean the scope was designed to be mounted on all of those bases. And since you were consistently low on all shots, then that tells me that is the problem.

Calculated* Actual

300 yards 2.0 * 4 1/4
400 yards (you did not label) * 8 1/2
500 yards (you did not label) * 17

So when you run out of travel the first item that will correct the problem is to put the scope and rings on a canted base, such as a 10 MOA or 20 MOA. Another option (though I don't prefer on heavy recoiling rifles) is Burris Zee rings that have polymer inserts that build in cant. But I have seen scopes slide inside the rings even though the rings were torqued properly.


Will you relabel what calculated corrections were as well as what DOPE turned out to be?

Pardon me Sir, only one of my scopes has turrets. All the rest are elevation and windage adjustments. However, they still all "click" regardless of whether I have to remove the caps or not. They are all described as being 1/4 MOA. However, 1/4 MOA is not 1/4" at 100 yds. Close, yes, but not exactly. Everyone I've ever heard describe movements uses the terms "clicks". Mind you I don't spend a lot of time with "snipers". Good day...

Yes they click. Happy?

I've already mentioned 1/4 MOA is not the same as 1/4 IPHY. That's the reason ballistic calculators speak in both of those as well as Mils. They are not interchangeable.

When a guy is having a "puzzling scope problem" it sure makes it easier to help him if he would provide numbers that are easily understood so that they can be cross referenced with a couple of other ballistic calculators to find the problem. I can do that if I have those numbers instead of "clicks".

I have but two friends and one acquaintance that are snipers. The rest are precision shooters that speak in MOA, or MIls. IPHY can be substituted to find the problem here, snipers or not.

If the ammo is running 3000 fps, with a 150 grain TTSX with a BC of .450, here are your come ups with a dead on 200 yard zero.

These are in IPHY (or 1/4" clicks)

200- zero
300- 2.1 IPHY (which is 8 total clicks up)
400- 4.7 IPHY (which is 18.8 total clicks)
500- 7.7 IPHY (which is 30.8 total clicks)

Swarovski shows this scope has 58 IPHY of internal elevation available. I am not certain how you describe your come-ups in your original post if you are adding your clicks to the previous adjustment, or if that is your total adjustment. Looking at the predicted come-up data looks about right. Since you said you could not get to 500 yards.

If you have 56 IPHY of available elevation, your scope is canted up, and not down. From a 200 yard zero, and you can not get to 500, that tells me you have about 7 to 7.5 IPHY up elevation, which leaves about 49 IPHY down. If you put a 20 moa base on the rifle, you would have about 29 IPHY up and about 27 IPHY down.

Also, lose the term "clicks". Convert over to IPHY, and this will make things much easier. "clicks" can be very confusing, especially how you described your come-ups. I don't know if you added your "clicks" the the previous come up or that was a total amount of "clicks" up at that distance. If you said I dialed 2.5 IPHY to 300 and 5 IPHY to 400, it would tell me exactly what you dialed and what your come up is. The main thing you need to find out is the speed of the bullet, and apply that to your dope chart. We need further info to diagnose your problem.

^^ Exactly!!

Factory spec on VOR-TX 7 Rem Mag 150gr TTSX is 3000fps. I can't believe it would be so far from that as to cause the issues you've listed above. I'm betting on the mount.

exactly and why I'm puzzled at this point why it took 17 clicks 200 to 300, 34 total 200 to 400, and 52 total 200 to 500.

again, same exact rifle and ammo with the Z3 I got the results as expected in the quote.

I understand why many like talking in PHY in my case or MOA. However, my self trained system working with iSnipe everything in my mind was in clicks to have in its simplest form. I shot 2 Aoudad and an Antelope with that setup 400+ yards. It was simple as looking at the iSnipe corrected chart and for that yardage dialing in the exact number of clicks. Sure you can do PHY and MOA, but you're still doing an extra calculation to figure number of clicks. If you have a numbered dial and already at zero you can eyeball it, but hope there is enough light those times the big bucks are usually moving. I better learn how to do it in the twilight though, because entire reason I'm working with Bruce is to get a custom yardage turret.

I'm curious to hear more about the MOA rings and mention that to Bruce.

Unless something else figured out looks like I need to chrono, but can't believe that since chrono was correct previously with same rifle and ammo.

from the little I know and have discovered so far, I agree. if I hadn't used this exact same rifle and ammo before with the expected ballistic results, then I would be doubting the ammo. I guess I'm still doubting the ammo now because I want to buy a chrono, but I don't think that's it.

if you guys don't think this is puzzling, then you are better men than me.

rifle = consistent tight groups
ammo = consistent tight groups and previoulsy charted perfect (chrono to be 100% sure)
range = confirmed distances high end range finder & google earth
weather = no factor
scope = elevation test OK
mounts = ???

For what it is worth, I had an older Swaro scope that you could pull the turret out from its normal position which were 1/4" MOA at 100yds, and with the turret pulled out, it was 1/8" MOA per click at 100yds. Maybe they put the wrong "guts" in the scope and yours is all 1/8 adjustments.

that was my first thought, because my range values are almost exactly what 1/8" PHY would be.

200 yard zero
300 yard 4.25 PHY
400 yard 8.5 PHY
500 yard 13.0 PHY

I personally would not mind having that level of adjustment, but sounds like you shoot a lot farther than I do. Let us know what you figure out on this.

sorry, now you guys have me confused and above is where you DON'T want to use PHY. I should have said...

200 yard zero
300 yard 17 clicks
400 yard 34 clicks
500 yard 52 clicks

66 IPHY is a bunch, Bruce just told me that my scope is spec for 58 IPHY, but that is minimum and many have more.

the problem is I want a custom yardage dial and based on the expected scope and ammo specs I should have got 750 yards in single turn instead of 500 yards.

here is quick little info page on MOA mounts.

http://www.egwguns.com/moa-faq

Even with a 0 MOA mount, I believe 1/4" IPHY should still produce expected IPHY values.

Being my number of "clicks" are almost exactly double for each distance from what they should be, I still think I have 1/8" IPHY internals. It is clearly labeled 1/4" IPHY though.

One thing I noticed were how fine tuned and small the "clicks" were compared to my Z3. It might just be the higher level of scope, but also might explain 1/8" gearing?

never mind, I did the elevation test and confirmed it was 1/4" IPHY.

now any way my adjustments in the field didn't match or same results as elevation test? as you said, can the scope sometimes produce a 1/8" or 1/4" with the same click. I just can't believe it.

I like "clicks" and I count them, maybe it's part of my OCD. When shooting at night and turning turrets I have to count clicks. Sure would be nice if somebody made the turrets glow in the dark

well, the answer was the most obvious and 1st guess, but one that neither I or the shooting expert could believe! the factory Barnes TTSX 7 mag 150 gr was shooting 2650-2750 fps vs. charted 3000. I have used the Barnes forever with great success, I think it is one of the best factory rounds because they are so experienced to start on the custom side. I will contact Barnes and do more research, but possible my rifle might have a problem taking 300 fps off the shot? I had my 30-06 out too with Barnes TTSX and it actually shot 100 fps more than charted.

the good news is the scope appears to be perfect and my Barnes TTSX 7 mag from 3 different boxes is all shooting consistent and tight groups. Once I entered into iSnipe the proper fps then everything lined up perfect. I shot out to 500 yards nearing 1 MOA and I'm not a great shooter (I was using lead sled).

Not trying to belittle anyone, but I shoot several times a week at different distances. I am often guilty of counting the clicks so I don't have to look at the dial. I personally have counted the clicks in the wrong direction and then had to dial double to get back on target. I'm not saying that is what you did, but I am saying it is possible for an experienced shooter to do that... p.s. also make sure the thick end of the rail is in the back...

I inputed the exact fps Barnes had charted. On top of that I have shot the exact same rounds through exact same rifle with results exactly as charted. Only thing that changed was the scope, so that's why we were so intent analyzing that first.

I called Barnes and they were very interested. They are sending package to return no charge some of my live and spent ammo. They say expect some variance, but 300 fps too much.

I realize you did all that, but if you didn't load the ammo yourself, you cannot assume a muzzle velocity. Even when we change lots of the same model of powder we recheck and rechronograph the load. Also making notes on abient temperature to find any velocity variances due to temperature changes.

MV is wrong, and the whole predicted trajectory will be wrong.

I bet they were! 10% variance is not good.