I have a Leupold “Prismatic” sight that before today hadn’t been used in many years. The first shots with the gun I mounted it on were close to the point of aim, but did require both windage and elevation adjustments. What became immediately obvious was that although the windage adjustments were moving the point of impact laterally, the elevation did not change.

It occurred to me that I had seen advice to periodically run scope adjustments through a range to keep things moving freely, so that’s what I did: up/down, left/right through significant adjustment ranges. Voilà: now the elevation works and I was able to zero the gun.

I have always been a bit leery of messing with the settings once a rifle was zeroed and I wouldn’t be making further adjustments based on the type of scope and gun, but it’s probably a good idea if it’s a good scope and we’re confident it will return to zero after the process.

I am curious whether anyone else has had problems with scope adjustments not working properly.

I am quite sure many will "shit their britches" with the advice.

If the scope has sat for stored for long periods of time... it will develop a resistance to changes in movement. Essentially, the windage and elevation adjustment is a set of screws that move the reticle.

I have found that an adjustment followed by a "light tapping" of the knob will free up the movement. Or just move it and shoot - recoil is essentially the same.

Good luck
Andrew

My experience is the cheaper the scope, the less likely it is to adjust precisely. There are articles on ‘shooting the box’ with scopes. That is basically shooting a box with adjustments, then ending up back in the same corner as started. One moves each direction a set amount.

Of course, with a cheap scope it would be nearly impossible.

I will often go a little beyond where I want to go, then back off to the intended adjustment. I also try to sight in near the power I plan to use, hunting, whatever. Some scopes can have slight differences over the power range.

I’m familiar with the “light” tapping, and I did that with the Prismatic. I don’t know if it helps but it can’t hurt, and it seems to placate the scope spirits.

quote:

Originally posted by sourdough44:
Some scopes can have slight differences over the power range.

Something I was surprised to learn about scopes with second focal plane reticles is that they can be susceptible to point of impact shifts when the magnification power is changed. I remember hearing about POI shifts like that with variable power scopes long ago when they were first becoming popular and as far as I know they all had second FP reticles. I didn’t know it was still something to be aware of, and although I don’t remember the source for that now, it wasn’t just some vague Internet claim.

Yep... The light tap with a nylon faced hammer can work.

I took a peak from the peanut gallery on impact point shifting with scope power adjustments. Whatever consensus I found was ‘it can depend’. With the average hunter, 100 yard or so zero, average shooter, maybe not enough to matter or notice.

One’s shooting ability may well have a larger effect than any scope impact change.

You get to the 600 yard+ benchrest shooters, they seem to want to leave the magnification set, not change anything during the shoot.

One would have to check for themselves, with their own gear.

I did a test years ago with my muzzle-loader, basically point of impact change, 75 yards, clean verses ‘fouled’ barrel. In my testing there wasn’t enough difference with impact to make me want to prematurely foul my bore. I was shooting Blackhorn 209, but in general don’t like my m-l having a fouled bore any longer than needed.

Just a somewhat related comment about the M-L testing, impact changes.

Yes, there a lot of things that matter more in theory or at least don’t matter much to the average shooter. POI shift with second focal plane reticle magnification change is probably one example. Going to a public range just before elk hunting season is always a reminder to me about how many (most?) hunters are really not very competent shooters.

And yes, that makes me a snob, but when I see someone shooting his 300 Win Mag with a rolled-up coat as a rest and is satisfied when four out of five shots go into 6 inches at 200 yards (and the “flyer” 2 inches farther out is ignored), I don’t really imagine that a 0.5 MOA shift between 4 and 12× is something he’s going to so much as notice, much less worry about.

But then I will give credit to at least trying to confirm that the bullets will go where they are aimed.

I've experienced wonky elevation and windage adjustments from both of the Leupold Mark 4s that I have owned. Sometimes called turret lash -- moving the Leupolds' turrets in one direction too often didn't produce consistent and repeatable adjustments. I learned to over-dial the require adjustment by a few clicks, the dial back to the desired setting. This is one of the reasons I haven't purchased a Leupold scope in many, many years. I gave one Mark 4 away and the other is in a storage box somewhere in my basement. Probably will never buy another Leupold again.

quote:

Originally posted by sigfreund:
...but when I see someone shooting his 300 Win Mag with a rolled-up coat as a rest and is satisfied when four out of five shots go into 6 inches at 200 yards (and the “flyer” 2 inches farther out is ignored)

Ignoring "flyers" is common -- at ranges, in discussions, on websites. I suspect one wouldn't have to search through all that many SigForum threads to find someone who attempted to discount a flyer or two. We all throw rounds, but not everyone owns all their shots.

The popularity and reputation of different scopes is something that interests me, starting when it seemed like the popularity of Schmidt Bender scopes suddenly dropped some years ago. I knew a couple of competitive shooters who had seven or eight between them, and then I noticed that all of a sudden some vendors were evidently clearing their stocks. I still see them in use by foreign teams in military sniping competition videos, but not much other apparent interest.

Leupold is also strange for the opposite reason. I read precision rifle blog articles, and not too long ago Leupold scopes were way down on the popularity list among high tier shooters, but the last list I saw from a year ago showed them in number 2 spot right after Zero Compromise and ahead of Tangent Theta. Some years ago a friend had a tracking seize up problem with an older Leupold and I’ve seen more than one older complaint that they “wouldn’t track.” Now, though, that’s apparently changed; PRS type shooters wouldn’t be choosing them if that were still true.

And then there’s Nightforce. Again, some years ago a former senior member of a Tier 1 military special operations unit told me that one of the manufacturer’s lines was “crap,” (but others were okay). I see lots of NF scopes on military sniper rifles and I noted that the Secret Service had them at the time of the attempted murder of President Trump.

But something I’d never heard until I ran across it just by chance is that their top ATACR line (and others?) is subject to tunneling at lower magnifications. Like a lot of other users who probably never turn the power down to the lower settings, I didn’t notice it with my 7-35×, but when I checked, sure enough: Based on the field of view at low power it’s actually a 8.5 or 9× to 35×, not 7-35.

And don’t get me started on all the Chinese stuff that all the YouTubers are in love with. Every once in a great while someone will admit that this or that feature or characteristic isn’t that wonderful, but that’s very rare.

S&B's reputation went south when way too many of their scopes developed vertical tracking issues. I know two buddies had new S&B stop tracking a few months after purchase. A distributer in Boulder also had a number of his customers' S&B scopes go tits up. Frank Galli (owner of Snipershide site) had a couple S&B scopes go bad. But yet another shooting buddy has owned a crap ton of S&B scopes and never had issues with any of them. Many moons ago, S&B sponsored a number of PRS-type shooters, and that put a lot of S&B optics on rifles. S&B also had an issue that their compact-length PM scopes were clear in the center of one's view, but optical quality went south really quickly as one looked further away from the crosshairs.

Speaking of an optic where clarity falls off noticeably once the eye strays very far from the crosshairs, look no further than March. For an expensive scope, the ones I've looked through were really sub-optimal even a couple of mils away from the crosshairs. Near the edges of the glass....ugh.

I've only seen a couple of upper level steel-match competitors use Leupold scopes. The shooters stated they were great scopes. What I looked through looked good, and the turrets felt good.

Vortex sponsored a crap ton of PRS-type shooters a while ago, with new optics available at a big discount each year. Many of the sponsored shooters sold their older scopes every year, getting new ones with the proceeds. This also put a lot of Vortex scopes in the field. Vortex had a reputation for vertical tracking errors on scopes that were used for a couple of years. As a result, a number of guys wouldn't use them for very long. But Vortex has a great warranty, so scopes that shit the bed were quickly replaced. I've heard that Vortex has a boatload less issues now with tracking durability.

Nightforce didn't take the PRS-type shooting by storm. There were initial issues of (1) SFP, (2) not-so-good reticle designs, (3) emphasis on MOA, (4) blue-ish tint to the glass. NF had a reputation for being absolutely tough as nails in the field, with virtually no turret tracking problems. As NF developed better FFP & mil & reticles & clear glass, their popularity increased noticeably. A number of NF optics show tunneling at the lowest magnifications. I see it on some of my NF scopes, but it isn't a big issue, as I don't use the bottom 10% to 15% of the magnification range all that often.

I can't say anything bad about TT. Every scope of theirs I've looked through was really good. If my bank account could tolerate the financial hits, I'd probably have a fleet of rifles with TT optics.

I know buddies who state Kahles scopes are just about perfect. They looked and felt good to me.
I haven't seen a ZC optic up close.

I've seen way too many Chicom scopes fail in PRS-type matches due to tracking issues. The scopes tend to have bright & clear glass, however, which seems to impress the folks with limited understanding of what makes a complete optics package.

I just thought of something else with tunnelling and magnification. FWIW, I've seen it on S&B, Leupold, and NF scopes.

PRS-type shooters often keep their scopes in the 12-15x ballpark throughout a stage.

Field-type steel matches regularly have more generous time limits per stage, greater distances between targets, and more stable shooting positions. There tends to be more adjustments to magnification here, and a regular use of higher magnification levels.

The run-and-gun versions of steel matches sometimes have some pretty close targets on stages, for which low magnification may be used here and there. IMO, this is the most common place in competition where tunneling might be an issue -- especially if the shooter is using a scope with its highest magnification at 20x or more.

I don't expect tunneling to be a practical issue for folks who shoot from stable positions, no shooting time limits, and no bouncing between targets. AKA bench rest shooting, which is just about 99% (OK, I overstate a bit. But only just a bit.) of the target shooting that's reported on the majority of gun-enthusiast websites. I regularly see folks state they're using 15x or more at 50 yards. And 20-25x at 100 yards.