Adjustment Repeatability...

[Ron Ankeny]

First off, I did read Zak's article and it's great. Here's the deal, I took my Swarovski Nova scope off of my .30-.338 hunting rifle and I want to replace it with a scope for some long range varmint and big game hunting. The rifle is nothing fancy, just a sporter with a 26 inch tube, but it shoots way under 1 MOA and it's time to see what this rifle will really do.

I stuck a 6.5-20X Long Range varmint scope on the rifle and worked up a drop chart. After two days of shooting I have verified the drop chart from 100 yards out to 800 yards. Alas, the scope doesn't reliably return to exactly to zero.

So, in the middle price range which scopes are just nutty reliable for repeating to zero? All ranging is done electronically so I don't need a hybrid reticle. Will the Leupold Mark IV cut it or do I need to dig really deep?

[George]

My Leupy (a 3.5-10x Vari-X III) does a 24 click up, over, down and back over square fine and ends up putting the rounds back in the same hole after completing the test.

My cheaper, non Leupold scopes do not, but my $1000 ACOG will. Money talks, crap glass walks ;-)

BTW, try tapping the scope housing after making the adjustments to make sure the reticle isn't sticking from friction, then creeping into place during the recoil from firing.

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Regards,

[Ron Ankeny]

George:

I am presently using a Vari-X III 6.5-20X Long Range Scope that I had "factory tuned" by the guys at Leupold. After a couple of days of constant adjustments I have found that particular scope to be close, but no cigar.

Hmmmm...now that I think about it, I did spend the summer shooting prairie dawgs while using that scope. I have cranked it up, down, over, and back hundreds of times, literally. I wonder if it is getting sloppy from normal wear and tear?

Edited September 19, 2005 by Ron Ankeny

[tightloop]

Let Leupold refurb it...

[George]

The other thing, which I mentioned is that the reticle does not always go to it's final new position until after the first (or second) recoil of the next group. This will open up a group fer' sure.

I always, always, rap the turret smartly after any amount of adjustment, on any scope to make sure it sticks (or doesn't as the case may be). A smart rap from a loaded cartridge upside the turret works wonders. You are basically smacking it upside the head ;-)

This is so often the issue here, it isn't even funny.

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Regards,

[John Dunn]

A Leupold should return to zero. If all the obvious things are tight (bases, rings) and the scope isn't returning, it's broken. Send it to Leupold and have them fix it.

If you are looking for a scope in a price range between Leupold and USO, Schmidt & Bender, etc, I'd go with a 5.5-22X Nightforce.

Rapping the turrets sounds like a good idea. I normally turn past my zero by two clicks, then go back the two clicks to the exact zero to remove any backlash. And no, I don't know what backlash is, I don't know if it really does anything or not. Someone smarter than me recommended it, so that's what I do.

[titandriver]

Ditto on the NightForce --- I'm running a 3.5-15x50 on my Vais-built .30-.338. I'm smoking 190 gr. Berger VLD's at 3220. Great medicine at 1000 yards!

[Ron Ankeny]

John:

The scope goes back on a varmint rifle and I still need a new scope for the .30-.338. I'll look into the Night Force. Is the Night Force ahead of the Mark IV?

Rich:

I am shooting a 180 Ballistic Tips at 3100 fps for prairie dogs. I nailed one Saturday afternoon at 823 yards. That's way short of the Varmint Hunter's 1000 yard club, but quite a way out just the same.

[Sam]

I am shooting a 180 Ballistic Tips at 3100 fps for prairie dogs.

Damn.......So, what's your elk load?

[JD45]

All of the die hard and not so die hard benchresters at my club tell me the same thing: Weaver has them all beat for repeatability. They are more than likely talking about the fixed power target models.

I have a Weaver 4-16X on a varmint rifles that is very repeatable. However, my deer rifles all wear Leupolds, and their glass is way better than my Weaver.

[rkgsmith]

The Leupolds should always return to zero. We use them on our duty rifles. On a target or hunting gun a miss due to a scope problem can really piss a guy off. However a problem with a scope on a duty rifle can be a disaster.

[George]

John, you are doing exactly the same thing by going past and returning to it. Eliminating the backlash is a very good way of looking at it. The movements of the reticle are very small and any friction in the path of the part that is moving and the move may not stick until the next time the scope recieves an impact, or more input is applied by the adjustment screw.

The 20 click square test at 100 yards gets me a pretty nice 5" square with the groups pretty much right at the corners when I tap the scope after each 20 clicks. I get less exact results when I just crank and shoot. The groups then usually exhibit a couple fliers that look like they are lagging the group back in the direction the last series of clicks came from. This says it all to me.

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Regards,

[John Dunn]

The Nightforce is a great scope. It's what Lauck is putting on his high zoot one mile rail guns, and he is a durability fanatic. I like mine a little better than my Leupolds, but I have over a half-dozen Loopys, and only one Nightforce. The NXS line looks tough...that alone is reason to get one!

[Ron Ankeny]

I just got off the phone with the technical support people at Leupold. The Mark IV scope works the same way internally as my Vari-X III long range scope. The mechanism that moves the reticle is identical. The only difference is the dials. For instance, take a Vari-X III scope in 3.5-10x40 with a fine duplex reticle, then add the conventional target turret/dials and you have a Mark IV 3.5-10x40 PR long range. Take the same Vari-X III, add a mil dot reticle and M1 dials and the result is a 3.5-10x40 LR/T M1. That info comes straight from Leupold.

So to answer my own question (John was right) my Vari-X III 6.5-20 LR operates internally the same as the Mark IV 6.5-20 LR/T M1. That's a sobering thought when you consider how many guys swear by the Mark IV, but consider the Vari-X III a piece of junk.

[Stuck in C]

A VARI-X III or Mark IV should return to zero, but... Another reason to use a Horus H25 or Mildot reticle and precise holdover rather than adjusting the knobs.

[TRG65]

I have a VXIII LRT model that is about 4 years old and a new mark 4. I have never had an issue with the VXIII, but just got the Mark 4. When I took it to the range last night a clicks worth of movement was not what I was getting when I would click 2 up and one back. I would get 1/2 to 3/4 of an MOA shift. It is a M1 not an M3 so I shouldn't be seeing MOA shifts And for big moves I'm not just for the little sub MOA fine tunings that I got the M1 for.