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18 mm VS 22 mm front sight

Posted: Mon Aug 20, 2007 1:07 pm
by Paul
Could you please let me know what are the advantages of using a 22 mm front sight over the standard 18 mm ? Thanks !

Posted: Mon Aug 20, 2007 2:14 pm
by Guest
On a standard length barrel? I imagine it would just be bigger, maybe brighter?

With an extension tube it gives more room for the proportionately larger elements used, and also keeps the tunnel itself looking roughly the same size as an 18mm tunnel/no tube.

Tim S

Exeter

Posted: Mon Aug 20, 2007 8:08 pm
by EdR
I believe the main idea is for better foresight contrast, I guess if you use a bloop tube than it'll look about the same size as a 18 on a standard barrel. Ross precision makes a 30mm. I just use the normal 18mm front

22mm fore sights

Posted: Tue Aug 21, 2007 6:32 am
by peepsight
Hi Paul

More or less every thing thats been said about the 22mm fore sight is about right. However, the main reason for the increase in diameter was to give you a bigger picture surrounding the target and let more light through to the aiming eye.
Having said that i still use an 18mm fore sight for indoor air rifle but i am considering trying a 22mm.

Peepsight

Posted: Wed Aug 22, 2007 8:48 pm
by Jose Rossy
It's hard to explain how incredible the view is to anyone who hasn't tried a 30 mm sight.

30mm front sight

Posted: Thu Aug 23, 2007 5:25 am
by rbs
Not certain that young eyes would benefit that much from the 30mm front sight, but sure helps my (57 yr old) eyes get a clearer and longer picture with a lot less fatigue.

Fore sights

Posted: Thu Aug 23, 2007 8:10 am
by peepsight
I'm sure the 30 mm fore sight gives a great sight picture but don't forget that if you shoot any ISSF regulation shoots you are limited to a maximum fore sight dia. of 25 mm.

Peepsight

Posted: Thu Aug 23, 2007 2:52 pm
by Tim Conrad
For air rifle, ISSF limits you to the 'normal' 18 mm globe. Free/Sporter have more flexibility. I use the 22mm with a tube, to get a similar sight picture to the 18 on a standard barrel. I would not use the big guy without a tube, you won't see much around it. Light reaching your aiming eye is mostly limited by the rear aperture. Set it to what works. It is a bit harder to maintain alignment with the 18 on a long tube, but more than a few folks manage. Whatever works best for you. If you switch, you do have to buy new apertures. As I recall, the adjustable wasn't cheap.

Posted: Thu Aug 23, 2007 5:43 pm
by B.T.Carstensen
Tim Conrad wrote:For air rifle, ISSF limits you to the 'normal' 18 mm globe.
Are you sure about that, my P700 came with a 22mm front sight if you could only use a 18mm then I doubt FWB would send a 22mm front sight with all of there guns.

-Brian

Posted: Thu Aug 23, 2007 7:48 pm
by Tim Conrad
Rule 7.4.3.7 allows a maximum front sight diameter of 25 mm for air rifle, so the 22mm globe is legal. I don' have an old rule book, but I think that is a change in the last quad. May have happened at the same time the higher riser block (up to 60 mm from center of barrel to center of sight) rule went into effect.

Re: Fore sights

Posted: Sat Aug 25, 2007 9:02 am
by Jose Rossy
peepsight wrote: if you shoot any ISSF regulation shoots you are limited to a maximum fore sight dia. of 25 mm.
Not a big concern in the US, where US NRA rules have no such prohibition. If I ever find an ISSF match around here, I can just switch back to the old 18 mm sight.

Posted: Sat Aug 25, 2007 11:40 am
by Tim Conrad
Depends on the match: NRA International rules follow ISSF, usually with a year or two lag, so the 25 mm rule applies. Up to the match sponsor as to which rulebook applies to the particular match. I've never shot a match that wasn't NRA International, USAS or ISSF.

Like front aperture size, this could create lots of rock throwing. If you make the front globe too big, it will fill the rear sight and you will see lots of little motion. Won't break as clean a shot, and in the extreme case, you will start to see fringe lines around the front sight, which makes accurate alignment even harder. Few people will agree on where that starts to happen.

Obviously, do what works best for you.

Posted: Sat Aug 25, 2007 1:32 pm
by Jose Rossy
Tim, I can guarantee you that a 30 mm foresight is not too big and it makes aiming much easier.

Considering the fact that the Right Sight by Stallings Machine includes a Crizal 1.5X magnifier (legal for NRA Highpower and Smallbore) it provides a marked advantage over a similar 22 mm sight.

Posted: Sat Aug 25, 2007 3:49 pm
by JohnD
The 25 mm sight tunnel diameter restriction in NRA International Rifle only applies to Air Rifle and Standard Rifle, not to Free Rifle or Sport Rifle. Rule 3.7 applies to Free Rifle sights, while Standard and Air Rifle sights are subject to rule 3.7 and Figure 2. See http://www.nrahq.org/compete/RuleBooks/ ... le-w03.pdf
and http://www.nrahq.org/compete/RuleBooks/ ... Illusd.pdf