UTG 3-9x40 scope adj. problem, or just limitation?

Hey guys, thanks for the replies.

The RWS lockdown mount is a droop compensating mount. Plus, I do have the arrow pointing to muzzle. And as stated in OP, the mount/gun setup worked fine with a RWS 4x, and a BSA 4-12x.

http://www.pyramydair.com/s/a/RWS_Lock_Down_1_Pc_Mount_w_1_Rings_11mm_Dovetail_Barrel_Droop_Compensation/2406

I don't know how to send pics, but it would just show the scope, and mount installed on the gun. I'm using this mount on another 34, in .177, with fine results. And as already stated, the mount on the .22 works fine with other scopes.

Thanks, Chuck

 Hi Mentolio, thanks for the reply.

I guess I used the wrong terminology when I said I'd "zeroed" the scope. Anyway, I did optically center both of the UTG scopes. Sadly, when trying to attain sight-in at 20 yards, they both would have the knob come off of the scope. Just like unscrewing a bolt, that only had 3 threads, from a nut.

I have no idea if they're defective, or merely have extremely limited adjustment? I guess I'll have to contact Leapers/UTG and see what they think. At this point, both are unusable on airguns, and this is why I bought them.

As I mentioned in OP, I have the UTG 4-16x50 on my .177, and couldn't be happier.

Thanks, Chuck 

Hi again Mentolio, and thanks for your continued interest.

I'll try to answer your first question..... I used a large, tapered reamer. It has the same taper angle, or really close, as the scope's bell angle. The mount itself has a length of around 120mm. The 1" portion of the scope is around 117mm. I just reamed the 120mm L of the ring portion ID, mostly front and a bit on the rear, to end up with around 112-114mm L. Anyway, I ended up with clearance front and rear. While not really uptown I suppose, it was effective for my purpose.

In the meantime, I installed another lockdown base, and yet another, different brand of scope. I sighted in again at 20 yards. And thanks to knowledge gained from this forum, I pulled the scope off and checked where the cross hairs were, in relation to its true optical center. They were in the same, really high position as the other scopes were. Only difference being, I figure, is this scope had a much larger adjustment range than the UTG scopes.

After all this, it was obvious the scopes and the mounts weren't at fault. Being ignorant on break-barrel airguns, and thinking barrel droop would be dealt with by the mounts, I missed the obvious. I checked the visual droop on the problem 34, in .22 cal, against my .177 34. The .22 has at least twice the amount of droop. It amazes me that they'd turn out a gun with this defect.

So I reckon my only recourse is to buy some adjustable rings/mounts, or send the 2 month old gun in for repair. I'll probably go with the adjustable rings/mounts.

Well, it certainly wasn't the UTG 2 scopes' fault.

Again, thanks for the help,
Chuck

Hi 30cal, yeah, that does sound a bit scary.......... )

I'll think about that a day or so. And just might try it. I'm an old, retired mechanic/welder, and have been fixing stuff all my life. I do have the equipment to make a "bender", so there's no problem figuring how to set-up like the Pyramid blog showed. Thanks, (I think) for the idea........ )

If I decide to do that, I'll report back here with the results.

Thanks, Chuck

Hi spysir, thanks for the comment.

I'm going to dig through my tools to come up with the needed components to make up a screw press. While I have my head finally wrapped around the so called straightening process, it just pisses me that the barrel/breech itself is perfectly aligned. The actual mis-alignment is in the breech to action? mating surfaces. Ideally, metal would be removed from the action? surface, to allow the barrel to tip up the needed amount.

While I can see how tweaking the barrel itself would address the scope/POI problem, I would be bending a perfectly straight barrel/breech to counter the breech/action interface. Please excuse my poor terminology in trying to explain this gun's particular problem, but it's the best I can muster. Anyhow, I know what I'm trying to say............ )

Thanks, Chuck 

Hi guys, I've got the problem mostly dealt with.

After looking further, and ciphering on it, I decided to try and correct the breech to action mating. I figured taking metal from the breech was the only way I could help the problem, to correct the excessive droop.

I removed the sealing ring and shim, used a marking pen to blacken the breech surface, then closed the action fairly briskly a few times. I then used a new, flat, fine toothed chainsaw raker file, to start removing the shining high spots. I only used around 3/4" strokes, to stay true. After cutting a tiny bit, I'd clean up the surface, re-black, then close the action a bit more. 3 times during the process, I'd clean things up, replace the shim and O ring, and go outside and shoot at 20 yards. Especially since the barrel and breech were so true to one another.

I am now using about 1/2 of the UTG's elevation adjustment to be dead on at 20 yards. But as the barrel is now almost perfectly straight, vertically, I don't think I'll file anymore. Apparently there is also some kind of problem with the RWS scope base/action/barrel alignment since I did have to use that much scope adjustment. If I took off much more metal at the breech to make things better, I'd be at zero droop. Or quite a bit more, and have the barrel pointing up. This would allow the scope to be closer to its true zero, but don't think that's a reasonable gamble.

Well, what I did turned out to be very easy, but if you try this, you'll have to be really patient and observant.

Again, thanks for all the help,
Chuck

A bit of an update:

After the above repairs, and re-mounting the UTG, I shot 6, 10 shot groups today. Using 3 different pellets, it was immediately apparent that setting the gun up as close to "optical center" as possible is a great thing. Groups were much better, with only 1 flier in 60 shots. Previously, I would get 10-12 fliers in this many shots. Would guesstimate groups are 30-40% tighter now.

While I don't want to pull the scope off to get a more accurate view of exactly how far I'm off of optical center, setting it up on a mirror and viewing as well as I can, it is off no more than one mil-dot. So I reckon the tension on the springs makes a great bit of difference.

Again, thanks for all the help.......... )

Chuck

Hi Danny, I understand your frustration......... )

As far as your question on how much metal I removed, that wouldn't make any difference on yours, or any other gun. There isn't a decent way, or a reason for that measurement. You would only remove as much as is needed to "lift" your point of impact to your desired spot. It would have to be done in stages, to only remove the amount needed. How I did it is in the thread you referenced.

I'll skim over the points you'll need to consider...........
With the gun laid on its side, pointing toward a light source (open window or any light), you can see how the barrel isn't aligned with the action. Remember how much.....

Open the action, remove the sealing ring, clean the breech surface of oils, then blacken that surface with a marker pen. You then close the action a few times. This removes some of the ink you've just painted on, showing the high spots. While it's hard to explain the technique in writing, I'll do my best. With action open and cradled with my knees/legs, I placed the file on the breech surface. With one hand applying very light pressure, I pushed the file with the other using around 3/4" strokes. After a few strokes, I'd clean off any metal filings, close the breech and recheck for progress, using the "light". Any good, fine bastard cut file that is around 5/8" wide, will work well.

I would guesstimate I did these steps 30? or so times. How many makes no difference. You need to be patient, remarking and refiling, how ever much is needed until you're satisfied. Patience, and good short file strokes are key.

Hope this is helpful, Chuck