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I've used the pinhole aperture on my glasses for many years, with a Hadley-style variable aperture on a rotating disc. Works well for both rifle and pistol, for me. Takes a little care in positioning the attachment, but the increased visual acuity and apparent flattening of the focal plane is noticeable. For a higher-quality truly variable pinhole aperture, Merit makes an iris-type adjustable aperture with a suction cup for the glasses. A pin-hole aperture close to the eye has long been a holistic remedy for nearsightedness/myopia.

I agree with Boats about bigger (aperture) is usually better, especially for long strings where shooter's eye fatigue becomes a major factor.
Good luck, Joe

boats wrote on May 15^th, 2007 at 9:49pm:



RIGHT ON!  When I was a kid my dad took me to a .22 match held at the college where he taught (put on by AFROTC).  We used Remmington 514T's with peep sights front and rear.  Even though I forgot my glasses (20:400) the officer said to just center that blur of a target in the blur of the front sight in the blur of the rear sight.  I won a turkey!  (Frozen of course)

Alan, that is an old target shooter's trick, and its purpose was to reveal exactly what you were concentrating upon, that is, sight alignment (with each other) and trigger squeeze. An experienced coach can tell, by the shape and position of the resulting group, where and how the shooter needs to correct his technique. I personally am not any kind of a coach but was fortunate enough to have had a good one in college, and saw him correct many flaws of mine and my fellow teammates merely by analyzing groups fired in this way. It works.
Regards, Joe

And they are????? 

For a front aperture I normally prefer a tinted plastic insert, like the ones that come in the selection with a new Lyman 17A, with the hole reamed out further, but these aren't legal in some matches. Managed to find a card with larger metal apertures, made by Ron Long as I recall, that were a big improvement over the Lyman steel apertures, but I still like the plastic ones better. The Ron Long aperture card contained at least two that were larger than the largest Lyman ones, and that was what I needed.
Good luck, Joe