efoleyjr wrote:If you think that your "+0.25 astigmatism" lens was hard to adjust you should try and get a sph= -2.67 cyl= +1.75 @ 51* lens lined up in shooting glasses. If you can get it right you must have your head in EXACTLY the same spot each time. If I could attach the lens to the sight I could get it right and it would stay in the same spot. I only ware the contact to shoot so that may be a problem also. What people are missing in the NSRA rule is the exception that allows a "corrective lens" to be attached to the shooter or rear sight.
Ed
Yeah, I was playing with a -6.25/+1.25/132* lens, so I feel your pain. And i want my rig ISSF legal, so that rules out the handy dandy lens bracket on the rear sight. Not that the US NRA listens to shooters, but have you tried bringing the corrective lens exception to the attention of the Smallbore committee? You might need to bring a letter from your OD with you to Bristol this year, but that would totally be worth it...
It is allowed in US NRA prone matches and that rule was changed a couple years ago. The main issue is the UK NSRA rule for the dewar match which I think clearly states that a "corrective" lens on the sight plus Eagle Eye in the front is allowed by the exception stated. KennyB from London is checking with their rules people. If I go with offset sights it will be a non issue as my left eye is excellent.
Ed
I'm sorry for the confusion with my earlier post. The rules as posted are indeed the NSRA rules. Rule 8.4.3 allows both an Eagle Eye lens in the foresight, AND a single vision correcting lens in the rearsight. I know shooters at my club who shoot with this arrangement, and who regularly shoot at the NSRA meetings in Scotland and at Bisley. I'm pretty sure that Kenny will get the same answer from the NSRA. There is one consideration with the correcting lens in the rearsight, and that is to what standard is it allowed to correct the vision. I know that many shooters have the correction lens in glasses set to +0.5 Diopters from their normal distance vision. I'm not sure if that would normally be allowed in this situation.
I only mentioned the fact that we have two different governing bodies for smallbore and fullbore target rifle shooting, knowing that in the US you have the NRA as the governing body for both types of target rifle, at least at a domestic level. As I noted the NRA (GB) does not allow both the Eagle Eye and the rear corrective lens combination in Fullbore TR.
AFAIK a single corrective lens is OK under NSRA rules, irrespective of the prescription. since the rule makes no mention of the prescription. Gehmann type dioptres are not permitted with a magnifying foresight lens, because the dioptre lens is also magnifying. A normal lens won't make the target look larger, only clearer as it just corrects the focal length (and/or astigmatism).
Last edited by Tim S on Tue Apr 07, 2015 9:12 am, edited 1 time in total.
Alan,Tim and David,
Thanks for your reply and I never though that there may be a "modified NSRA rule" in place. Maybe the NSRA can help but the NRA in the US is difficult to work with. The shooter in the US going for a Dewar team are told to comply with British rules and as I read the rule the corrective lens on the sight is OK. We will see where KennyB gets his response.
Ed
Last edited by efoleyjr on Tue Apr 07, 2015 5:47 pm, edited 1 time in total.
Currently, to the best of my knowledge. the NRA of A is using the Dewar Handbook prepared by Bill Lange and me in 2007.
For me the most important section is the NRA Liaison Officer's duties which require him to bring the donuts and juice. I am always a wind coach, and never a shooter, so my priorities are different. For more details than you might care to know along that line please feel free to read the attachments.
However, for those of you are shooting better than me the Handbook states, "Sights permitted: Metallic sights only, NSRA Rule 8.4.1.2 A rearsight, including tube sights, which may if so desired have attached a single lens or system of lenses not containing an aiming point as a substitute for, or in addition to, prescribed spectacles. Plane light absorbing filters may be used. Ref: Appendix A Paragraph 12 and Appendix B" If I remember correctly the reference is to NSRA Rules of 2007.
I just checked the NSRA website and the same wording appears today, minus the Ref:..., with a statement that it is current as of April 1, 2015.
Best,
Hap
Noted Devourer of Dewar Donuts, Dewar Groupie, and Wind Coach Broker to the Stars
I have just had an email from our UK "guru" on non-ISSF rules.
He believes that the latest version of the "Dewar International Match Conditions" has not been updated to the latest NSRA rules regarding sights.
He therefore suggests that the current rules for the match include:-
"Sights - Only open or aperture sights may be used. Telescope and other optical sights are not permitted. A lens may be used attached to, or forming part of the foresight in addition to prescribed spectacles, but not in addition to a lens or system of lenses attached to the rearsight."