TargetTalk

The sights misaligned by 2mm very bad
The sights alignned but misaligned to the target (at the percetption of the shooter) by 2mm, very bad.
The sights aligned, aligned to the target but off by 2mm at the target, is enough to change score...and still bad.

David Levene wrote:

cqbarms wrote:If you are meaning that there is a 2mm difference in sight picture (realtionship of of sight to target) perceived from the shooters view, of the sight being low or high by 2mm viewed at say the front sight, that' is absolutely substantial!

If you are saying that in reality the sight picture is 2mm different high, low left, right, at the target (as a net effect of the difference in sight picture however that may be perceived by the shooter ) again...2mm is a LOT, it's the difference between a 10.x and a 10.x -2mm, a 10 and a 9, a 9 and an 8. Take a look at a scoring guage for finals...is 2mm at the target a lot? I would say so.

If the sights are perfectly aligned with each other but offset by 2mm then the shot will miss the centre of the target by 2mm.

If the there is a mis-alignment of the sights of 2mm then the shot will miss the centre of the target by 50-60mm (assuming 10m Air Pistol).

I think this is the best of it that there can be.

Roy Nagel wrote:Think two kinds of sighting error -- parallel and angular.
Parallel sighting error occurs when the sights remain accurately aligned front to rear, but the gun drifts so it points to the outer part of the aiming area -- the sight picture has deteriorated. A 5mm drift in the sight picture = 5mm away from target centre -- a 9 or an 8.
Angular sighting error occurs when the front blade is not precisely in the centre of the rear notch, although the sight picture remains perfect (gun pointed correctly at the target).
A 1mm angular sighting error (sight misalignment) on an airgun with a 350mm sight radius translates into this:
1mm X 2.9 (multiplier of the sight radius to a metre) X 10 metres = a 29mm displacement of the shot on the target! Not a 10 but a 6!
Now, the tough part -- one of the biggest causes of angular sight error is jerking the trigger or pushing the gun on trigger release. And one of the factors in that is uncertainty over sight alignment AND sight picture -- often caused by the shooter using a pistol with a long sight radius (and maybe muzzle-heavy).
With some new shooters in our group, we've used a small hose clamp to reduce a sight radius from 350mm to 150mm, and guess what? They got the shot away easier, with less drift, less push or tug on the trigger, and tighter groups on the target.
Is it for everyone? No. but some shooters benefit from both a shorter sight radius and shorter barrel on air pistols -- that's why they're made.
My point in this and previous posts is that shooters shouldn't feel handicapped because they are more comfortable shooting a shorter gun -- properly set up (sights, pellet, velocity and fit/balance) it will deliver just as many centre 10s.

Read the subject Title.
How come we are rehashing old arguments when there is a question yet to be discussed.
Take a look at the postition of the rear sight blade on a long and short barreled Morini in relation to the thumb/trigger finger web and see the difference.
Forget about sight radius.
What are the peculiarities with the positioing of each?

If we extent the sight radius to, let’s say one meter and at the same time use this meter so that half the distance is beyond the hand towards the eye. The rear part will move more relative to your head/eye than the front sight thus it should give more information. Now, everyone realize that a rear sight so close to your eye is not normal but I have never the less seen a shooter holding his gun 15 cm from the eye. That was his best way to solve a problem. Eyes are different. Somewhere ends the benefit of moving the rear sights back. Free pistols have had the possibility of moving rear sights back if they wanted to do so. Did they? No.
I do not think a sight radius of 25 or 30 cm makes any difference but if the barrel is short the only way to get 30 cm is to extend rearward. And if you tend to look more on the rear sight then the front sight it may even be wise to use the rear extension.

IF your eyes like the rear sights further back then you do not need a long front heavy pistol. And you can always put on extra weight if you like.
I’ll vote for short barrel Morini, MI if you want to adjust the grip. Or LP10.

Kent

CQBArms:

Wow.

Miss a day, miss a lot!

Hope the following doesn't sound too "know it all"-ish, but reading the thread has been very frustrating. We (not just you and I, but the "Royal We") have a huge gap in understanding between us as to just what the heck is going on to shoot a ten.

By your postings, it appears as though you are assuming that shorter dwell time (therefore shorter TLT) is better-

- because there is less time for the centerline of the bore/point of impact to stray from the "perfect" sight picture when you decided to release the shot.

Why on earth would anyone assume that you are sending the "squeeze" command when the sights are perfectly aimed; and that additional delay causes the shot value to deteriorate?

Does a major league baseball player start swinging the bat when the ball is perfectly positioned over the plate, in the strike zone?

If you wait for perfect sight alignment to command the release of the shot, you will be shooting no tens at all and a whole buttload of nines.

No, really- and I mean this with no disrespect intended- you need to spend some time thinking about the shot process and how a ten is really produced. And then apply this model of the shot process to the whole question of "dwell time."

It is not impossible for a flintlock shooter- even with TLT measured on a calendar, not a clock- to shoot a ten!

(ps Yes, please calculate the change in total lock time from a 7 inch to a 5 inch- better yet, go ahead and use a 9 inch to a 4.5 inch barrel change. Then map out how much distance the muzzle would travel during that time. Then rethink how much difference a shorter barrel would make, *even if* you assumed that you are commanding the release of your shots when the sights are perfectly aligned.)

Steve Swartz