Iron Sight Offset Blocks

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efoleyjr
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Iron Sight Offset Blocks

Post by efoleyjr »

Does anybody have any experience with offset iron sights,shoot right & aim with left eye? If so please share your experience. Also, does anybody have a set of offset blocks for sale?
Ed
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Andre
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Re: Iron Sight Offset Blocks

Post by Andre »

My apologies, perceived the question wrong.
Last edited by Andre on Mon Apr 06, 2015 11:44 am, edited 1 time in total.
efoleyjr
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Re: Iron Sight Offset Blocks

Post by efoleyjr »

I am trying to aim with my left eye using a right hand rifle. Blinder will not solve the problem. Thanks
Ed
mtncwru
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Re: Iron Sight Offset Blocks

Post by mtncwru »

http://www.mec-shot.de/en/products/sigh ... ght-shift/

That's more what Ed is looking for, Andre. The link you posted is for bringing the sight backwards, not left/right.

http://www.intershoot.co.uk/acatalog/TE ... r-774.html
Those would also work. I, personally don't have any experience with them, nor does anyone in my club that I know of. I'll keep my ears out, though.
Last edited by mtncwru on Sun Apr 05, 2015 3:19 pm, edited 1 time in total.
Martin Catley
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Re: Iron Sight Offset Blocks

Post by Martin Catley »

Sorry probably no use to you but may be of interest. My Father used offsets with a lot of success with both Smallbore and Fullbore Rifles.
It must be nearly forty years ago when he started using them due to Cataract in his right eye. He cut them out of bar steel using a file and hacksaw a set of offsets for an older 1411 and his Omark. He held Range records with his Fullbore set up shooting off the right shoulder and using his left eye.

I have seen a modern offset assembly but not sure who made them, they looked to be very well made with adjustment for width. May have been one of Anschutz,Centra etc.
KennyB
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Re: Iron Sight Offset Blocks

Post by KennyB »

No reason you couldn't shoot well with offset sights - the downside might be if you want to shoot at different distances...

Depending on how much cant is required to get your eye behind the offset rearsight it might not be as bad as this (or it might be worse) but if we assume that the sights end up perfectly upright:

coming up from (say) 25 yds to 50 there would be a horizontal shift of around 2.5 inches to the left (if you're offsetting your sights to the left of the barrel).
So your rearsight would have to come right by 5 MOA as well as up by 2.25 MOA (or thereabouts).

Coming up from 50 to 100 wouldn't be so bad - again around 2.5 inches left which is only 2.5 MOA at that distance - with a vertical move of around 7 MOA.

If the sights (and rifle) end up canted to the right (which they would be with my head position) then there would be less horizontal shift as you come up.
So as well as raising the cheekpiece, some sideways movement might also be in order as you go between distances.

One upside would be that you'd notice any variation in cant immediately as you wouldn't be looking through the center of
the peephole anymore...

That's how I interpret the geometry anyhow.

Ken.
efoleyjr
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Re: Iron Sight Offset Blocks

Post by efoleyjr »

KennyB wrote:No reason you couldn't shoot well with offset sights - the downside might be if you want to shoot at different distances...

Depending on how much cant is required to get your eye behind the offset rearsight it might not be as bad as this (or it might be worse) but if we assume that the sights end up perfectly upright:

coming up from (say) 25 yds to 50 there would be a horizontal shift of around 2.5 inches to the left (if you're offsetting your sights to the left of the barrel).
So your rearsight would have to come right by 5 MOA as well as up by 2.25 MOA (or thereabouts).

Coming up from 50 to 100 wouldn't be so bad - again around 2.5 inches left which is only 2.5 MOA at that distance - with a vertical move of around 7 MOA.

If the sights (and rifle) end up canted to the right (which they would be with my head position) then there would be less horizontal shift as you come up.
So as well as raising the cheekpiece, some sideways movement might also be in order as you go between distances.

One upside would be that you'd notice any variation in cant immediately as you wouldn't be looking through the center of
the peephole anymore...

That's how I interpret the geometry anyhow.

Ken.
Ken,
Thanks for your thoughts. I only shoot american prone on US and metric targets at 50 yds,50m & 100yds so L/R changes should be fairly small and I also shoot with very little cant to the left. I have been shooting with a contact in my right eye with a fair amount of success but lose too many matches by a couple points and X's that are the result of to many soft sight pictures. After fighting this problem for 3 yrs and not ever being able to get a consistant clean sight picture I am going to using my left eye which has very good vision. The MEC offset sight brackets look like they can control cant so that may be a good choice for equip. Thanks for your help.
Ed
bugman1955
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Re: Iron Sight Offset Blocks

Post by bugman1955 »

Ed, I used them some time ago. I found with the Right Sight I can get as good a sight picture as I could using the offset sights for my left eye. Don
mtncwru
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Re: Iron Sight Offset Blocks

Post by mtncwru »

I also used to shoot in contacts, and had issues with drying eyes, moving contacts, and an inconsistent sight picture. Have you considered a pair of shooting glasses instead of the contact? Or, since you're only shooting NRA prone, you could even mount the lens straight on the gun. Might be easier/cheaper than going down the offset route...
efoleyjr
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Re: Iron Sight Offset Blocks

Post by efoleyjr »

mtncwru wrote:I also used to shoot in contacts, and had issues with drying eyes, moving contacts, and an inconsistent sight picture. Have you considered a pair of shooting glasses instead of the contact? Or, since you're only shooting NRA prone, you could even mount the lens straight on the gun. Might be easier/cheaper than going down the offset route...
I have several different lens for my Champion shooting glasses in an attempt to eliminate the contacts, some are close but not right. The main problem is my astigmatism and the sight picture is never as good as the gas perm contact lens which smooths the cornea. Problem is the dry eye, and constant changing of focus. My left eye is almost perfect so after 3 yrs of trying the right eye I am going to the good eye. If I use a lens mounted on the sight I can not shoot on the US Dewar team as the brits do not allow them. Thanks for the ideas.
Ed
Last edited by efoleyjr on Mon Apr 06, 2015 7:18 am, edited 1 time in total.
efoleyjr
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Re: Iron Sight Offset Blocks

Post by efoleyjr »

bugman1955 wrote:Ed, I used them some time ago. I found with the Right Sight I can get as good a sight picture as I could using the offset sights for my left eye. Don
Don,
Thanks, I will be trying them.

Ed
KennyB
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Re: Iron Sight Offset Blocks

Post by KennyB »

efoleyjr wrote:If I use a lens mounted on the sight I can not shoot on the US Dewar team as the brits do not allow them.
Are you absolutely sure about that Ed?

If you use an Eagle Eye in the foresight and a lens attached to the rearsight then I'd agree - but I don't think that a standard (non-magnifying) foresight with a lens or magnifying diopter in the rearsight would be a problem under our NSRA rules.

It would be illegal for ISSF but I believe the NSRA are more tolerant.
I could ask Phil Martin if you'd like - he's competitions director at the NSRA and should be able to settle the matter...

Ken.
efoleyjr
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Re: Iron Sight Offset Blocks

Post by efoleyjr »

KennyB wrote:
efoleyjr wrote:If I use a lens mounted on the sight I can not shoot on the US Dewar team as the brits do not allow them.
Are you absolutely sure about that Ed?

If you use an Eagle Eye in the foresight and a lens attached to the rearsight then I'd agree - but I don't think that a standard (non-magnifying) foresight with a lens or magnifying diopter in the rearsight would be a problem under our NSRA rules.

It would be illegal for ISSF but I believe the NSRA are more tolerant.
I could ask Phil Martin if you'd like - he's competitions director at the NSRA and should be able to settle the matter...

Ken.
Ken,
A year or so ago I asked the same question of Paul Gideon and his research came back that I could not use a 0.5d lens in the fore sight and attach my corrective len to the rear sight. I think he is wrong and here is why, please read this UK rule.
"8.4 RIFLE SIGHTS
8.4.1 The Association recognizes the following types:
8.4.1.1 Open. Open, V, U or bar with or without wind gauges.
8.4.1.2 Aperture. A rear sight, 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.
8.4.1.3 Telescope. Any form of telescope.
8.4.1.4 ‘Single point’. Aimpoint, red dot and similar single point, optical sights.
8.4.2 The definition of ‘iron sights’ is either Rule 8.4.1.1 or 8.4.1.2; the definition of ‘optical sights’ is either Rule
8.4.1.3 or 8.4.1.4; the definition of ‘any sights’ is Rule 8.4.1.1, 8.4.1.2, 8.4.1.3 or 8.4.1.4.
8.4.3 A lens may be used attached to, or forming part of the foresight in Rule 8.4.1.1 or 8.4.1.2. The lens may not be used in addition to any other lens or system of lenses except a single prescribed sight-correction lens. The sight-correction lens may be either attached to the rear sight or worn by the shooter."

The rule clearly states that a corrective lens can be attached to the rear sight or shooting glasses. I would be interested in hearing the conclusion from your side of the pond.


Ed
BigAl
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Re: Iron Sight Offset Blocks

Post by BigAl »

I'm pretty sure that there are shooters at my club that use both an Eagle Eye in the foresight and a vision correcting lens mounted on the rear sight. It is important that you check the NSRA rules for the UK and NOT the NRA (GB). Our NRA only controls Fullbore TR in the UK and as I recall they DO NOT allow a rear correcting lens with an Eagle Eye.

Alan
efoleyjr
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Re: Iron Sight Offset Blocks

Post by efoleyjr »

BigAl wrote:I'm pretty sure that there are shooters at my club that use both an Eagle Eye in the foresight and a vision correcting lens mounted on the rear sight. It is important that you check the NSRA rules for the UK and NOT the NRA (GB). Our NRA only controls Fullbore TR in the UK and as I recall they DO NOT allow a rear correcting lens with an Eagle Eye.

Alan
Alan,
I thought that the "8.4" quoted above was the governing rule. I guess I will have to check. I did not realize that you have two governing bodies. Thanks
Ed
efoleyjr
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Re: Iron Sight Offset Blocks

Post by efoleyjr »

Alan,
I just checked and the "8.4 rule" quoted is the NSRA rule.

Ed
David Levene
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Re: Iron Sight Offset Blocks

Post by David Levene »

efoleyjr wrote:
BigAl wrote:I'm pretty sure that there are shooters at my club that use both an Eagle Eye in the foresight and a vision correcting lens mounted on the rear sight. It is important that you check the NSRA rules for the UK and NOT the NRA (GB). Our NRA only controls Fullbore TR in the UK and as I recall they DO NOT allow a rear correcting lens with an Eagle Eye.

Alan
Alan,
I thought that the "8.4" quoted above was the governing rule. I guess I will have to check. I did not realize that you have two governing bodies. Thanks
Ed
8.4 quoted is an NSRA rule.
mtncwru
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Re: Iron Sight Offset Blocks

Post by mtncwru »

From the program for NotPerry this year:
"Anyone wishing to be considered for the Dewar Team should fire the metallic sight matches with “British legal” equipment, i.e., 40 mm sling, optics in front or rear sight, not both."

So you could mount the corrective lens in the back, but you would need to lose the Eagle Eye up front.

Do you only use the contact when you're shooting, or do you wear one all the time? I used to wear glasses all week at work (I was an ICU nurse, and liked having a physical barrier between my eyeballs and other people's bodily fluids), then would swap in the contacts just for shooting. I noticed that my contacts didn't correct as well after the first day. My optometrist pointed out that this was my eyeballs getting reshaped/irritated by the contacts because they weren't used to them all the time. By not wearing them during the week, my corneas were in a constant state of flux. It wasn't enough to notice when I was walking around looking out of both eyeballs, but it was plenty to notice when I was looking out of one eye down a stack of concentric circles at different focal distances. Starting to wear contacts more frequently helped this greatly.

I finally squeezed the trigger (har har har...) on Lasik this year. Even after that I had a +0.25 astigmatism in my shooting eye: again, nothing that I noticed day to day with driving/walking around, but plenty to notice behind my sights. Getting the lens setup on juuuuuuust the right axis took some doing, but even a few degrees of rotation (about 1mm of rotation on my 34mm lens) made a difference. Once I finally got it in the right spot I was much happier, happier than I ever was with contacts.
efoleyjr
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Re: Iron Sight Offset Blocks

Post by efoleyjr »

mtncwru wrote:From the program for NotPerry this year:
"Anyone wishing to be considered for the Dewar Team should fire the metallic sight matches with “British legal” equipment, i.e., 40 mm sling, optics in front or rear sight, not both."

So you could mount the corrective lens in the back, but you would need to lose the Eagle Eye up front.

Do you only use the contact when you're shooting, or do you wear one all the time? I used to wear glasses all week at work (I was an ICU nurse, and liked having a physical barrier between my eyeballs and other people's bodily fluids), then would swap in the contacts just for shooting. I noticed that my contacts didn't correct as well after the first day. My optometrist pointed out that this was my eyeballs getting reshaped/irritated by the contacts because they weren't used to them all the time. By not wearing them during the week, my corneas were in a constant state of flux. It wasn't enough to notice when I was walking around looking out of both eyeballs, but it was plenty to notice when I was looking out of one eye down a stack of concentric circles at different focal distances. Starting to wear contacts more frequently helped this greatly.

I finally squeezed the trigger (har har har...) on Lasik this year. Even after that I had a +0.25 astigmatism in my shooting eye: again, nothing that I noticed day to day with driving/walking around, but plenty to notice behind my sights. Getting the lens setup on juuuuuuust the right axis took some doing, but even a few degrees of rotation (about 1mm of rotation on my 34mm lens) made a difference. Once I finally got it in the right spot I was much happier, happier than I ever was with contacts.
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 wear 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
Last edited by efoleyjr on Sun Apr 19, 2015 12:46 pm, edited 1 time in total.
mtncwru
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Re: Iron Sight Offset Blocks

Post by mtncwru »

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...
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