Things just don’t stay the same

[Windmill01]

I only own 4 air rifles. An LGV, a Hw77 Stainless ( I know it’s not stainless but that what it’s called) a Hw50S and my trusty Benjamin Titan. All fitted with Airmax scopes. All very accurate. I have had a couple of Airmax’s replaced over the years due to failure and I now seem to be having these wandering poi issues again with all my rifles. Once upon a time I could take either rifle from the safe and I knew that I could humanely dispatch a pest with the first shot, but not now as I can’t be guaranteed a clean kill. 
I have returned a couple of scopes recently for issues of the reticle not moving when turning the knob only to have it returned saying that the scope was at the end of its adjustment and was stuck. I would hazard a guess and say that they were at the end of their adjustment because I had to rezero each time I used one of them. I mechanically centre all my scopes first and then adjust, some require more adjustment than others and now still require further adjustment each time I shoot one. I’ve done all the usual checks so no issues there. Depending on how many pellets I shoot the poi can change in the middle of a session. Surely all 4 scopes can’t be faulty.
Yesterday it was raining so I started shooting my Titan, guess what poi was off about half an inch at 25 metres. It was dead on when I put it in the safe last time. So I mechanically centred it again and shimmed and shimmed and shimmed and shimmed until I got poi within a couple of clicks either way of the bull. I’ll shoot it again today if I get a chance. I know I can buy an adjustable scope mount but what I’ve looked at nearly cost the same as the scope. So what gives, I never had to rezero any of my Airmax’s before until now, maybe at the beginning of each season or on very cold or hot days but this is very frustrating.

Gary

 

[Franklink]

Springers.

Most are incredibly finicky to changes in pressure points. And it's not a problem you can buy yourself out of b/c even the high dollar ones exhibit the same characteristics. 

We never want to blame ourselves as the shooter, but it is very often the guy pulling the trigger that is responsible for wandering poi with springers. 

 

[phillip]

It has been my experience that spring guns are notorious for point of impact changes. I learned a long time ago that if I shoot one of my spring guns that have been in the safe for an extended time, it will almost certainly need to be zeroed again. They’re usually not off by much, but enough that I take notice. 


I’ve learned to accept the POI change as a normal occurrence when shooting my spring piston rifles and simply adjust my scope as necessary.

 

[GoldenStateAIRGUNer]

The issue really isn't the POI change. That happens! What matters is if you can still cluster shots.

 

[AirShot]

Each time you cock your springer it takes in new air...is that air warmer, colder, drier, more humid??? All these things cause air to compress differently!!! Then consider expansion and contraction of metals in action and in the scope. Then also consider the lubes inside the action, are they stiffer, more runny from heat?? Everything affects springer accuracy, but....unless your using top quality scopes it could be a scope issue. One way to check is by shooting the square, this is recognized as a testing method for scope turrets repeatability. Adjusting the turret to far is a common problem, most all mfgrs recomend not going more than one full turn from optical center to adjust for O... If more is needed then an adjustable mount is recomended!!!! Shimming can be dangerous as it is so easy to bend a scope tube. With todays adjustable mounts, there is no reason to shim, not worth damaging a good scope for the price of a mount.. Even with my Leupold and Burris scopes the poi does change when the weather changes but only a small tiny amount...

 

[thumper]

Having them tuned to a more sedate power level, ensuring the piston seal fits well, and you don't use sticky or runny lubes makes them MUCH less prone to shift. 

My 77Ks and HW50S that I hunt with shoot the same in 85 degrees as they do at 30 degrees. But they have proper fitting parts and are lubed sparingly with moly/graphite paste. 

Hold sensitivity or the scopes could be your biggest issue however. I've had a few Airmax scopes over the years, and I'm sorry to say that they were all junk sooner rather than later. Every single one of them. 

So don't accept "it's just springers" because it absolutely doesn't have to be that way. If it were I wouldn't grab mine to go hunting with when I have to move a PCP out of the way to get them out of the safe...

 

[Arzrover]

Another possible contributor is the shims. Side focus scopes don't take kindly to being squeezed and you have to tighten them well to prevent movement.

Years ago, an article was written about scope shifting and springers. This fellow set out to prove that stresses on the scope were the cause. A brief synopsis is that he tested both expensive and very cheap scopes and when mounted with no stress, all would track and hold zero. He claimed zero failures over a lot of shooting with hard shooting rifles. I've not shot springers a lot since that article but have had no issues with shifting or scope failure in a good while.

His method of mounting was to wax the scope well, put a small shim on the rear mount if it was to be raised, and a small dab of epoxy on the mount, then tighten it lightly to force out the excess. The scope needs to be removed after it's set, but before its fully hard to make it easier. I've done this where I need some elevation but don't have adjustable mounts. 

Also keep in mind that the separation of the mounts must always be the same after doing that to maintain zero stress .

Something cheap and not too difficult to try...

Bob

 

[Brent]

I was taught if you can shoot a springer accurately you can shoot anything, but bare in mind they are very hold sensitive and poi can change with hold. Shims will work but be careful because you can damage the tube of scope if not. The lubes used a d the tune of gun as mentioned earlier can also cause issues if the weather is different ie hotter or colder. As it is stated there are too many variables to point you in the right direction at this point. But all have given valid points to look at.

 

[GoldenStateAIRGUNer]

Each time you cock your springer it takes in new air...is that air warmer, colder, drier, more humid??? All these things cause air to compress differently!!! Then consider expansion and contraction of metals in action and in the scope. Then also consider the lubes inside the action, are they stiffer, more runny from heat?? Everything affects springer accuracy, but....unless your using top quality scopes it could be a scope issue. One way to check is by shooting the square, this is recognized as a testing method for scope turrets repeatability. Adjusting the turret to far is a common problem, most all mfgrs recomend not going more than one full turn from optical center to adjust for O... If more is needed then an adjustable mount is recomended!!!! Shimming can be dangerous as it is so easy to bend a scope tube. With todays adjustable mounts, there is no reason to shim, not worth damaging a good scope for the price of a mount.. Even with my Leupold and Burris scopes the poi does change when the weather changes but only a small tiny amount...

" Adjusting the turret to far is a common problem, most all mfgrs recomend not going more than one full turn from optical center to adjust for O… If more is needed then an adjustable mount is recomended!!!! "

That is a good point! POI can change if your turret adjustments are to far in any one direction. A Iike a mechanically zeroed scope to be within 15 clicks of being on at 10 meters. Or less ! When you have to turn your turret adjustments near the end of it's travel to zero your shot at close range it effects the scopes ability to hold zero.

 

[TiredRooster]

I don't really ever experience any POI shift with my HW97. That can't be said with one of my PCPs. I can put the springer up and not shoot it for months. Then take it out, and it shoot just as it did before it was put up. I also don't use an "air rifle" scope on it either. I have a Vortex scope mounted on it and have been quite pleased with it. I don't know if my experience is an anomaly.......from what I read I sometimes think maybe so. But I own 5 air rifles......3 springers and two PCPs. The HW97 with the Vortex scope is the go-to rifle most of the time because it is so very consistent and I trust it.

 

[Windmill01]

Of my 4 air rifles the only one I have taken apart and “tuned” is my Titan. The other three are stock standard. All have been extremely accurate with no poi shift and I would often post pictures of 5 shot groups after after taking them from the safe. No poi shift and excellent groups. They are all individuals and are held according to their peculiarities. This is a group from my Hw50S straight out of the safe at I think 30 metres, no adjustment.

Both my Hw77 and Lgv were in the same ball park. Any one of the three could be relied upon straight out of the safe to humanely dispatch a pest. Not now. It seems that as the scopes have aged these poi issues have crept in.

The Titan was always the rifle I would go walk about with on our property, light easy to cock and shoot ( I put a lesser powered Gamo gas ram in it) ever reliable but again not now. We have moved down to the sea and by boat we are 15 minutes from beautiful Fraser Island, I wonder if this has something to do with it.

Gary

 

[Springrrrr]

Don't discount wind. Even a little bit of it can make quite the difference. Then there is "ghost" wind that doesn't show on flags, but is sneaky there. Wind will move a lighter pellet a good inch at 30-40 yards if not compensated for.

 

[thumper]

I'd clean the barrel if it were me. 

I shoot lubed pellets and pull a dry patch through mine every tin or so. 

I know some guys claim they haven't cleaned their barrels since Moses was in diapers, but I have found that mine need it every now and then. 

The salt air may be oxidizing some lead residue in your barrels or something. 

 

[Mg616]

Agree with others the right scope mounted properly on a smooth cycling gun with a clean barrel is a must have baseline. I had all that but put budget mounts on an R9, POI would shift just a little at first, then every time a bird landed nearby. Upgraded to Sportsmatch, took my time remounting then no issues at all for several tins (like a fool I then sold it).

So far (2 tins, 3 months) my HW50s with a Macarri tune kit is holding very well with a Hawke + Sportsmatch. 

 

[boscoebrea]

Shoot for groups.....are the groups tight?....if not check the tightness of all bolts,nuts,never over tighten thou....

This happened to me so often over the years that I do not adjust the scope,I just keep on shooting because I have found out the poa changes until the air gun gets handled; you know warmed up,sort-of-like for- play before playing with.....

Yea used to blame scopes,mounts weather,polidicks,etc...until I realized some things are just fussy and need to be handled .

Sometimes nothing works.....got to change the mount then....remember to center the scope clicks,start in the middle....know how many clicks your scopes has,never go to the extreme either way.....that is a no no.....

Mounts ,some of my springers have barrel droop,many RWS do and I needed a drooper mount...got to go ,good luck

 

[Windmill01]

So today was the first chance to test my Titan at 25 metres after shimming the heck out of the scope. The groups on these two photos appear ok. I haven’t cleaned the barrel, but I have checked the stock screws, pivot bolt and everything else that can affect your accuracy. No wind also and same conditions, overcast. Held the same as always so to me ( the uneducated) it appears the scope is the issue. What do you guys think?

This is the first group.

This is the second group. Interestingly the flyer in both groups was on my last shot and my grouping improved on the second bull.

 

[GoldenStateAIRGUNer]

G'day mate! Not to bad Gary ! When four out of five shots cluster that good you can rest assured that the one shot is on you.

 

[Windmill01]

G’day Wayne, it’s always been a pretty accurate rifle for a big box buy. I have a Sports match dampa mount on my Hw77 and the poi is shifting on that so I don’t think it’s the mounts. It’s seems to be a common problem across all my rifles, I’m stumped.

I have re zeroed the scope and tomorrow if I get time I’ll shoot a couple of more groups and see what happens.

Gary

 

[GoldenStateAIRGUNer]

G’day Wayne, it’s always been a pretty accurate rifle for a big box buy. I have a Sports match dampa mount on my Hw77 and the poi is shifting on that so I don’t think it’s the mounts. It’s seems to be a common problem across all my rifles, I’m stumped.

I have re zeroed the scope and tomorrow if I get time I’ll shoot a couple of more groups and see what happens.

Gary

When you innially zeroed the rifle did you have to turn any turret adjuster to the extreme in any one direction? 

 

[Windmill01]

I really can’t recall Wayne, I think both elevation and windage were moved more then what you would consider normal on all the scopes that I have fitted on it. I once tried a Bullseye ZR mount and had to shim that as well. I might splash out and buy a set of Sportmatch adjustable height and windage mounts. But they don’t have an arrestor pin and cost $262 Aus. Decisions decisions.

Gary