Question about AO scopes

[GD Giles]

What is the relationship between the AO and the reticle? It's my understanding that mildots come into play when you're shooting under or over the zeroed range, correct? So focusing the AO has no bearing on where the crosshairs end up, correct?

How do different zoom levels affect the crosshairs? I read somewhere that someone zoomed to a level that made the mildots useless in that the effective range of holdover was beyond the number of dots he could count in the view. By changing the zoom level, I'm guessing out, he then brought the mildots back into range by having the proper number to hold to achieve aim. What does this mean close up as opposed to far away?

I tired to zero my new AO scope today and after about 200 pellets failed.  Part of it was not my fault and in fact I'm pretty ticked off in that my gun is so violent that it backs the trigger bolt out quite easily so 2 days ago I cleaned it with bore cleaner, dried it off, then slathered it w/blue locktite. Let it dry over 24 hours and today, after about 100 shots, guess what bolt was lose by SEVEN turns of a screwdriver?  That was a lot of wasted time and pellets. I got it snugged up again but my groups were still wild and I, at this point being so frustrated, moved the target up to just 15 yards. I was still getting groups ranging from 3/4" to 4" at 15 yards. Oh well, try it again next week. I know one mistake I made was not using the max level of zoom to zero in. I started at low power and thought I'd move it up to see how the groups moved on the paper. I have no clue what I'm doing after reading and watching videos for hours. I will not attempt this again until I have a proper supervisor, ie an experienced shooting buddy.     

For the record, this is the 3rd scope I've tried to zero in and failed.    The gun is so violent it turns the IR on when I fire it.

[GD Giles]

Took me a bit to edit but I shot a video of trying to zero the scope. You can see the groups get progressively larger throughout the process as that trigger bolt got looser and looser.

[squirrel_hunter]

  what type scope you trying to use?i see people here say to use blue Loctite on them,i would use a small amount of red Loctite,i know someone going to chime in and say it non-removeable but it will come apart rather easy if you don't glob it on.also what does that screw go into on that rifle?i would check that also.i also will add I sending hatsan I received back and replaced it with a Benjamin summit NP2 22 and I am very happy with it.i hope it works out for you.good luck.

[GD Giles]

It's a UTG 4-16x40 AO scope. This bolt holds the trigger onto the cylinder/action of the gun.

[squirrel_hunter]

 I would try small amount of red Loctite and evenly snug the three screws down then tighten them down.i also feel that sometimes when screws(bolts)work against each other that it may cause them to loosen up.i looking into my rifle to see if that could happen.

[MRT949]

If you use RED YOU will not get it apart without heat .Use blue .

[squirrel_hunter]

 I have used small amount of red and taken it apart without the blow torch.if you have already used blue and it still not staying tight send it back if you can and try another one...

[Smoketown]

I cleaned it with bore cleaner, dried it off, then slathered it w/blue locktite. Let it dry over 24 hours and today, after about 100 shots, guess what bolt was lose by SEVEN turns of a screwdriver? 

GD,

Does the bore cleaner leave the surface clean and lubricant free?

The screw AND the hole it screws into MUST be clean, dry and lube free.

I called Loctite back in 1971 or '72 (no internet back then) and they suggested that I use acetone or lacquer thinner (along with a couple of other products that are no longer available ) and have had no problems since.

Don't get me wrong ... Shock and vibration along with a SHORT depth of engagement CAN cause screws to loosen if you don't use the correct grade even with proper cleaning.

As far as Red Loctite goes, be careful as I have twisted/sheared off 10-32 screws when I didn't use heat to soften the grip.

Cheers,
Smoketown

[GD Giles]

Not sure if it's a lubricant or not, I wouldn't imagine it is since that could lead to dieseling. The next best thing I have to clean it would be lighter fluid which cuts grease and dries in seconds leaving no residue.

[robertr]

 Acetone cleans very well also, you might be using to much locktite not giving it time to dry. Try using just enough to coat the threads. Also locktite works better with pressure, make sure the bolts are tight not just snug.

[robertr]

 If your rifle has that much recoil your scope could be toast, maybe check your poi with open sights.

[nielsenammo]

Not sure about your screw problem but I can answer your scope issue.

Although it can change scope to scope most 4-16 or 6-20 or whatever scopes are set to have have the "zero" of zoom set to 10 power in a second focal plane scope.  This means the mil dots are calibrated to be used at 10 power. So if you say each mil dot represents 3.5" at 10 power, at 20 power they will equal 7" and at 5 power they will equal 1.75".

So if you zero your rifle with the cross hairs to 50 yards and use a 2 mil dot holdover it will shoot 7 inches high at 10 power.  If you are at 20 power and use a two mil dot holdover it will fire 14" high.

They do make scopes that are called first focal plane where the power of the scope does not change how much each mil dot represents, it is the same throughout the power levels of zoom.  The drawback is the mil dots become larger which some people like and others do not.

As far as zeroing of your scope you need to get the rifle to put repeatable pellets on target before you can even dream of adjusting your scope.  If the pellets are not going in the same place shot after shot then you will chase the target forever.  Once you get your gun fixed I can tell you how to adjust your scope in just a few pellets.

Shoot a pellet while aimed at a fixed point, the smaller the point the better.  Then, re-aim your scope to that aim point again.  While keeping your rifle very still adjust your scope turrets until the cross hairs are covering the hole where the pellet was shot.  Re-shoot and make any fine adjustments as needed by repeating the same steps.  Sometimes it is easier if you have someone to adjust the scope while you hold on to the aim point the first time you do this.  Make sure your rifle is able to be held firmly with out moving around.

Hope this helps.

[Methuselah]

I tired to zero my new AO scope today and after about 200 pellets failed.  Part of it was not my fault and in fact I'm pretty ticked off in that my gun is so violent that it backs the trigger bolt out quite easily so 2 days ago I cleaned it with bore cleaner, dried it off, then slathered it w/blue locktite.

Just curious, have you cleaned the bore, have you added any lubrication to the spring chamber through the transfer port?

I wonder if you have detonation or dieseling.  If not sure try cleaning the bore with patches whetted with Simply Green or Goo Gone.  Then follow with dry patches.  Overcharging the gas ram is an "all bets are off" situation, whoever did that for you if they call themselves tuners, should have made sure it shot well before sending it back to you.  Just my opinion!

AO moves the focal point of the targeted image forward or backward.  You want the focus point where the cross hairs are and you move (head bob) to make sure it's there.  Just having an AO or side focus adjustment doesn't mean when the image looks to be in focus that it is exactly on the cross hairs, so if you don't head-bob, every shot at that setting where your eye isn't exactly in the same spot moves the POI by any error in parallax (factor of angle of view, and points defined by the cross hairs and where the image actually focused in front or behind those cross hairs).

magnification blows up the image.  If the cross hairs also have their magnification changing (first focal plane) you can use the dots for ranging, if not they are calibrated for only one magnification.

As for Loctite, red, blue, purple --- it's all super glue.  You could actually use super glue, but I wouldn't want to be the one trying to disassemble it even though heat will break it free.

[Smoketown]

As for Loctite, red, blue, purple --- it's all super glue.  You could actually use super glue, but I wouldn't want to be the one trying to disassemble it even though heat will break it free.

Lighter fluid should be OK as a degreaser as most of them are just naphtha/white gas ... Or so I have been told.

Loctite is SLOW drying ... Plain old Superglue can leave you with a screw half in and half out ... Don't ask!!   

I'm also pretty sure that they add something to the Loctite that shears, breaks or crumbles when you remove the screw.

Most likely more in the blue and less in the red. The blue being more opaque when applied to the threads.

Cheers,
Smoketown

[mpbby]

GD, I didn't understand what you mean by 'trigger bolt'.

In general, there are always SEVERAL factors involved and I think you are dealing with too many variables at the same time.
 
When you have time to be VERY patient - and - focused, I would attack the 'inconsistency' by parts, starting with - open sights at 10 yards:

- rifle? stock+action screws, main spring, seals, dieseling, ..
- pellets? always use the ones that fit better (not a kind of loose, not too tight); if it's the case, you may choose the "same" JSB in 5.52 mm heads, instead the 5.50; if you load a loosie, just disregard its POI.
- chrony? average, ES
- shooter's repeatability? holding, resting, breathing, focused, trigger squeezing, follow trough,..

Only if/when you feel comfortable, and are getting consistent and very tight groups with - open sights at 10 yards - I would think about the scope.  And then, there will be other several factors to consider.

By now.., hope this helps.

Marcos
 

[GD Giles]

Great responses, thanks all. What I'm calling the trigger bolt is actually a machine screw that holds the trigger housing snug through the stock into the action. I just checked it again and it was loose again. I removed it and there was virtually no locktite there at all. So I will fall on the sword and say I didn't clean it well enough. That said, I will clean the ever living fool out of it and the insert as well, best I can, and reapply the blue locktite and try it again.

Just tried to use the chrony and my interior lighting is not sufficient, which I figured as much, so I'm off to get some of those led work lights and try that, tomorrow probably.

[mpbby]

In the 350, the - trigger housing - is hold in the action by two crossing pins.  It has a 'threaded hole' (English..?) where the 'bolt' goes through the stock to hold action+stock..; as I think I'm understanding, maybe the same as your Hatsan.

This threaded hole was worn-out.  According to a mechanist, in my case there was no thickness to recover it. So, I had to buy a brand new trigger housing.

Hope it's not the case.

[GD Giles]

I don't think it's worn out yet. The gun only has about 600+ pellets through it.

Nick, you say that scopes calibrate to use the mildots at 10 power but my scope manual said to set it to 16 to zero. This is another thing I did wrong yesterday. 16 is tough relief to dial in and I knew I'd be shooting a lot so I backed it off. Next time I'll know better and just follow the manual.

[Scotchmo]

...
This means the mil dots are calibrated to be used at 10 power. So if you say each mil dot represents 3.5" at 10 power, at 20 power they will equal 7" and at 5 power they will equal 1.75".
...

On a SFP scope, the dot span is inversely proportional to magnification, so:

If each mil dot represent 3.6"@100 yards while at 10 power, at 20 power they will equal 1.8", and at 5 power they will equal 7.2".

[GD Giles]

well this is going to be airgunproshop's problem now. The gun is firing very slow so I've asked them to address the trigger issue while dealing with the low air issue.