Open Sights Offset

[billsnibby]

I'd be grateful if anyone could shed some light on the following.

I frequently shoot break-barrel springers with open sights, but have noticed over the last 2 to 3 months that I need to wind the rearsight almost all the way across to the right to be on target. This wasn't always the case, but I don't know what's changed. Relevant factors are;

It's not that windy when I shoot
I wear spectacles to correct severe short-sight, but haven't had a new pair or a prescription change
The laser boresight confirms the sight is offset to the bore when wound fully right
All 3 of my open-sighted guns are similarly affected
I put a bubble level on one gun to eliminate any canting (made no difference)
I don't appear to be leaning over the stock
Group sizes are OK at ranges from 10m to 40m
Offset doesn't change significantly with ammunition (0.177 AA Field, JSB exact, FTT)
Haven't cleaned the barrel
Both fore and rear sights are secure
Foresight blade is vertical when the gun is levelled, and on the barrel centreline
Rear sight top is horizontal when gun is levelled
No change in gun support (sitting, gun supported in hands, left elbow rested on a table)

Any thoughts as to what I could try would be much appreciated, as I'm beginning to run out of ideas!

Best Regards,
Bill.

[Patrick 2]

This is a difficult one but if it's happening with different rifles then the problem must lie with you some how but what it is ,there lies the problem.Have you tried getting someone else to shoot the gun(s) with the windage turned all the way to the right and see where the pellets go and if they go to the right that at least will confirm the problem is with you and not the gun(s).Sorry I can't be more help.

[thisisdonald]

is it possible that your eye dominance has changed?

this is a case for House M.D. if ever I saw one!

[MTA123]

Possibly you are pressing your cheek on to the stock more than you used to pushing the aim point left when it recoils. I have had similar problems.

[slugger]

my guess is either a change of hold recently [try the gun totally rested on shooting bags front and rear with no human contact except for the trigger]
or
and im leaning towards this idea. if your glasses are not perpendicular to the rear sight [nobody gets totally square-on] then is it possible that the lense angle is altering your percieved view point ?

[richardscar]

Personally I wouldn't worry about it Bill . when I was younger I had loads of different air rifles and pistols and I remember I often had the rear sights adjusted to the left ? I wasn't a bad shot then either, so maybe its just different eyes ?
This was even the case with rimfires and full bores . hth , Rich.

[angrybear]

It could be as simple as wearing a thicker jacket because its winter so you can't pull the stock in as tight, or a change of body shape through exercise or weight gain/loss.

[Rickenbacker]

Do you get a sharp focus on the front sight with your specs on Bill?

You say the glasses haven't been changed, but maybe your eyes have? Giving you more of a blurred sight picture than before?

Or, a scratch / scuff just in the wrong place on your specs?

Technique wise, if it were me, I'd concentrate on trigger and follow-through.

Otherwise, I'm stumped...

[billsnibby]

Many thanks to all for your valuable suggestions: its given me a few things to try this weekend, namely

(i) get someone else to try the gun(s) [ Why didn't I think of this? wood/trees etc.]
(ii) ensure a consistent & light cheek/stock contact
(iii) try rested on a shooting bag
(iv) try using other specs
(v) try to look through the centre of the specs. lens

I do ensure the trigger is central on the end pad of the index finger, and follow-through insofar as maintaining the point of aim and the trigger pressed until the shot has landed. Sight picture is sharp focussed sights / blurred target (target is a plain black spot on white background). Clothes have been similar over the period of the change.

Has anyone had any experience of the sports vision shooting assessment offered by Simon Goldsmith (Bristol) via JH Steward (Bisley)?

I might be unduly worrying here, but on one gun the rear sight is in the end stop and the others aren't far off!

Thanks again all and best regards,
Bill.

[richardscar]

Bill, if your groups are improving and you are hitting where you are aiming, just enjoy the shooting
unless you look like this ..http://oddstuffmagazine.com/wp-conte...-1934-1982.jpg

[TORNADOS7]

That's a difficult one buddy cos once they're set opens should never need touching again no matter who uses the rifle or whatever changes you make, the only thing I can think of is have you change pellets recently as that'll change your poi which would require adjustment of the sights !

The beauty of open sights is no parallax error, you can wear more/less clothing, put on or lose weight, wear glasses/don't wear glasses, basically no matter what you do the sights "if your using/aligning them properly" will always be on target !!!...

[thisisdonald]

did you try shooting with your left eye close (assuming youre a righty)

[junglie]

Try it without your elbow resting on the table or with a nice thick cusion or beanbag to rest on. i can't get good groups rested like you describe with springers.

[air-tech]

Fact: where a pellet lands with a springer does not have to have a direct relationship to where the barrel was pointing before the shot was let off.

Why? Because the gun starts recoiling, thus deviating from the point of aim, as soon as you pull the trigger and the piston starts to move. There is quite a lot going on before the pellet even starts to move.

So? Where the barrel ends up when the pellet actually leaves the muzzle depends on how the recoil changes the position of the gun in relation to where it was when you pulled the trigger.

Where exactly? Depends on how the gun is held. This is what hold sensitivity is about. Zero using one hold, change hold, and the barrel ends up elsewhere.

Translation? Barrel may well (and generally is) pointing off-target prior to the shot being let off. The gun then recoils, the barrel (assuming correct setup and consistent recoil management) then comes on target just as the pellet leaves the muzzle.

In your case recoil due to your particular hold means that the initial position of your barrel is off to one side a fair amount, which is why the rearsight windage adjustment is not inconsiderable.

If you are shooting consistently and you have enough adjustment available to you - no worries and well done.