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-   -   Do Lens Reducer's help you? Give opinion, please. (http://forums.thecmp.org/showthread.php?t=274073)

rubicon762 12-30-2020 11:01 AM

Do Lens Reducer's help you? Give opinion, please.
 
Hi all
Does a Lens Reducer help you?
I'm thinking of trying one for my Service Rifle competition.

Thank you in advance for your opinion/review.

Here's an example:

https://www.whiteoakarmament.com/whi...s-reducer.html

canes7 12-30-2020 11:12 AM

I’ve always thought no. I’ve understood that they are supposed to reduce parallax errors, but if you get a nice bright sight pic thru your scope, with no shadows, you have eliminated parallax.

ceresco 12-30-2020 11:56 AM

I use one for the sniper match. It is very easy to drift off from the center of your scope's field. The small aperture forces you to stay centered and reduces parallax error without the need for an adjustable optic. If you can maintain a perfect sight picture, you don't need either. Good Shooting. ...

Testelter 12-30-2020 10:25 PM

I use one made by HMR on my vortex viper and find that it really does help get a consistent head position. Worth checking out, Mr. Holub offers great customer service also.

X Hunter 12-31-2020 07:54 AM

Make a lens reducer by drilling the cap of a Butler Creek lens cover.
Start small and work the hole size up to where you like it.
If the reducer works, you can get a purpose made one from a supplier.
If it doesn’t work for you, fill the hole in the lens cap with silicone caulk and it’s still good to protect your scope from dust and bad weather.

Dave Stitz 12-31-2020 09:18 AM

Yes, They really help in keeping your head centered and show an obvious shadow when your head shifts a little.

Bml 12-31-2020 07:57 PM

My kid has a WOA lens reducer on the WOA service rifle scope. I have only shot rounds with it standing. It really forces your eye and head to the same position. It reminds me exactly like using globe sights. I will be getting set up with one soon.

HighpowerRifleBrony 12-31-2020 09:13 PM

Anyone have quantitative data like group mean radius?

A true "reducer" on the objective lens side is best for shortening the focal distance for dry firing. Otherwise reducing the eye box is stupid.
An aperture lens on the ocular side makes more sense.

Maybe growing up with an A2 beat sight alignment into me, but despite a 1.57" mount, I've not noticed a parallax issue the few times I've been to 600yds. I mostly got a smoke tinted aperture lens so I wouldn't fry my eye on a west facing range.

With a 3" eye relief, the 1/8" hole and 5/16" chamfer is big enough to clear my 20 MOA BDC with at least 10 MOA margin.

https://www.ar15.com/media/mediaFile...pg-1016751.JPG

Rootsy 01-01-2021 10:24 AM

I have used them. In the end it doesn’t seem to make much difference in my shooting. Parallax isn’t the issue it is truly correcting - on a 24 mm objective it is truly minimal. What the reducer is forcing is head position and pressure consistency. With iron sights that small aperture took care of that, the optic with its wide field of view allows you to become sloppy.

Gewehr43 01-01-2021 11:50 AM

Quote:

Originally Posted by Rootsy (Post 2000016)
I have used them. In the end it doesn’t seem to make much difference in my shooting. Parallax isn’t the issue it is truly correcting - on a 24 mm objective it is truly minimal. What the reducer is forcing is head position and pressure consistency. With iron sights that small aperture took care of that, the optic with its wide field of view allows you to become sloppy.

So I'm considering joining this century and going optics.........
I've been playing around with them and winding my way thru the various options.......

So I appreciate your input....as with the others who have actually used them.

My question is this:

So idea goes that you need consistent head position/cheek weld etc or else you will introduce parallax issues.....parallax leads to opened groups or wandering zero--(for lack of better terms).....

But if the parallax is so small (so affect on groups).. then why worry about it?

So then, of course, within reason, why worry about forcing your head/eye into a particular spot? (So no need for the reducer).......?

In other words if the affect on groups by the question of parallax is so small, why worry about going thru all these steps to correct or eliminate it?

Rootsy 01-01-2021 12:26 PM

Quote:

Originally Posted by Gewehr43 (Post 2000049)
So I'm considering joining this century and going optics.........
I've been playing around with them and winding my way thru the various options.......

So I appreciate your input....as with the others who have actually used them.

My question is this:

So idea goes that you need consistent head position/cheek weld etc or else you will introduce parallax issues.....parallax leads to opened groups or wandering zero--(for lack of better terms).....

But if the parallax is so small (so affect on groups).. then why worry about it?

So then, of course, within reason, why worry about forcing your head/eye into a particular spot? (So no need for the reducer).......?

In other words if the affect on groups by the question of parallax is so small, why worry about going thru all these steps to correct or eliminate it?

Parallax isnít the issue unless you have your eye alignment so off that the image is heavily shadowed and you are shooting very Close or very far. I once did a spreadsheet to calculate parallax and with a 24 mm objective and parallax set @ 300 yards maximum possible parallax error at 200 and 600 was only like 0.1 moa.

Varying head pressure and position creates varying loading on the rifle butt that causes shots to go where they were not aimed when you pull the trigger. With a huge field of view in a scope it is easy to get sloppy whereas with a .042 aperture it forces you to place your head consistently

Gewehr43 01-01-2021 01:40 PM

So I've also been reading the primer on the NM forum, which is quite good BTW.....

So short version:

So the parallax effect could be quite small, depending on the exact situation, but to minimize the variable as much as possible, you have several choices:

-choose a scope or modify so the parallax is set at, say 300yds, instead of say 100yds.
-For that matter choose one that has adjustable parallax.

-use one of these reducers to either:
+reduce the affect even more with the above.
+if you don't have a scope that is adjustable (or you haven't gotten it done).

-Or just rely on the idea that your cheek weld/head position is consistent enough and "drive on down the road....."
(because of course if you are really consistent, you have in effect, eliminated the parallax, because your head isn't changing shot to shot).

Is that in a nut-shell?

But you also bring up the idea of the FOV being too big generally...... Can you expand on that?

HighpowerRifleBrony 01-01-2021 09:14 PM

Quote:

Originally Posted by Gewehr43 (Post 2000092)
But you also bring up the idea of the FOV being too big generally...... Can you expand on that?

My interpretation:

Some relationship of exit pupil and eye "box". The eye can be moved around the ideal focal point some while still maintaining a full, mostly clear image. C_Does and 9-Hole Reviews have some great optic review videos, often showcasing the eye "box".

Whereas moving the eye 0.020" from ideal alignment would be obvious with a 0.040" aperture and 3" eye relief, many scopes wouldn't show misalignment unless they're rigidly fixed and the parallax is way off, say 30yds when shooting at 300yds. The reticle is relatively small compared to the ~1.5" ocular lens.

jcj54 01-03-2021 10:35 AM

Having shot scope in smallbore matches for 40 years, I can attest that keeping your head and eye in the same spot is critical. I regularly shoot 50 yard conventional prone smallbore with the local gun Club in the summer and have blown shots in the 9 ring by failing to keep my head position consistent. Pretty disgusting to shoot a 199 25X because of the error.

Danny 01-07-2021 09:10 AM

Quote:

Originally Posted by Gewehr43 (Post 2000049)
So I'm considering joining this century and going optics.........
I've been playing around with them and winding my way thru the various options.......

So I appreciate your input....as with the others who have actually used them.

My question is this:

So idea goes that you need consistent head position/cheek weld etc or else you will introduce parallax issues.....parallax leads to opened groups or wandering zero--(for lack of better terms).....

But if the parallax is so small (so affect on groups).. then why worry about it?

So then, of course, within reason, why worry about forcing your head/eye into a particular spot? (So no need for the reducer).......?

In other words if the affect on groups by the question of parallax is so small, why worry about going thru all these steps to correct or eliminate it?

Nooooooooooo

Gewehr43 01-09-2021 07:03 PM

Quote:

Originally Posted by Danny (Post 2001675)
Nooooooooooo

OK..... I'll play this game............

YYYYYYYYYEEEEEEEEESSSSSSSSS

What did I win?


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