TargetTalk

I'm a little confused on where exactly sight radius is measured from and what length is ideal.

So do you measure...
1. From the front of the action to the end of the rifle.
2. From the front of the sight to the end of the rifle.
3. From the aperture on the rear sight to the end of the rifle.
4. From the shooter's eye on the cheek piece through the rear sight and to the end of the barrel.

I've heard that 36 inches is supposed to be like the ideal focal point of your eye thus this is how long your sight radius should be.

Thank you,
Brian

Sight radius is measured from the rear sight aperture to the front sight aperture.
In simple terms its the distance between the two sights.

In finer detail, that's the rear sight eye piece pin hole to the front sight element where ever it is fitted in the tunnel.

Peepsight

Some would say that the longer the sight radius, the better.

Anonymous wrote:Some would say that the longer the sight radius, the better.

Indeed some might, but that oversimplifies the whole process of determining what is best, and in reality isn't correct.

Rob.

In air rifle the ISSF maximum length allowed is 850 mm. That's measured from the rear of the 'action' to the end of the muzzle.

With the exception of the Steyr LG-100 and 110, which are at the length limit, all the other makes are several cm shorter than 850 mm.
Thus, many shooters fit an extension on the muzzle to take full advantage of the length allowed.

It is a very personal thing to which sight radius you have but some shooters claim the extra length adds to sighting accuracy.
Extra long sight bases are probably seen more often in the prone disciplines where the extra length helps in sighting accuracy.

I wouldn't get too paranoid about these differences as many medals are being won with air rifles not at the full length limit, and more shooters shoot with out the extension than with.

Using the old adage, try it and see.

Peeps

RobStubbs wrote:

Anonymous wrote:Some would say that the longer the sight radius, the better.

Indeed some might, but that oversimplifies the whole process of determining what is best, and in reality isn't correct.

Rob.

OK, to qualify that - a longer sightbase will (by definition) reduce the effects of parallax error, meaning that any misalignment of the foresight, the rearsight and your eye will result in a smaller error at the target.

If your head position and sight alignment is absolutely perfect every time then the length of the sightbase is of no importance.

It wasn't all that important to to the winning air rifle shooters at the last Olympics, none had extensions fitted for longer sight base.
I think when you get to their standard, then consider the option.
Look at the ISSF TV and you will see very few people if any using extensions on air rifles and these are world class shooters.

Peeps

I think you better start worrying about that guy down in SC who's gonna whip your ass in the prone regional this weekend and NOT about your frickin' sight radius!! :) BP