History of the U-Notch Rear?

[msh]

Can anyone please provide some edumacation on the history of the U-notch rear sight?

Whose idea was it? Who was the first to prototype it? Who was the first to large scale market it? Have any studies been done on U-notch vs square notch rears?

Personal experiments are fine here, and anything from theoretical arguments to actual data I'd be interested in looking at. I'm of the current opinion that it's just a personal preference.

This question is more out of curiosity than anything. I've had a U-notch sight on one gun, and didn't really care for it. It was a S&W Shield and I was shooting a lot of double-stack Glocks at the time so my distaste was probably due more to gun differences than sights. I know some people really like them, Trijicon HDs are popular and it the U-notch was selected for the new FBI contract sights if I'm not mistaken. I've also heard arguments for the opposite rationale, i.e. the Spaulding Ameriglo sights used a square rear based on the theory that right angles are easier to align which I believe was quoted in a Youtube watched a long while ago.

I just found a set of old 10-8 brass bead sights with a U notch that came in the box of a second-hand Glock. I'd probably do some fairly rigorous experiments with matching Glock 19s or 34s if I had more time and didn't just switch to shooting 1911s for a bit.

[JHC]

Good question. I suppose the U notch has been around almost as long as handguns in one form or another but in recent decades, my perception is that 10-8's principal Hilton Yam has really argued for them. IIRC the theory is the eye centers up the post faster. I came to U notch 10-8s and Trijicon HDs from Warren square notch rears.

I'm agnostic on the whole question. I have shot and seen shot good precision and good speed with both. I don't really think square or U notch makes much if any difference vs other sight attributes.

[HopetonBrown]

I remembered liking this post from last year...

It appears that Mr. Cooper actually made his thoughts known on the matter. On page 103 his 1961 "The Complete Book of Modern Handgunning" he wrote, "A 'U' notch rear suffers because the light on each side of the front sight is less measurable, being curved and pointed."

[SAWBONES]

Interesting how individual perceptions differ.

A rear sight U-notch is problematic for me, as symmetric left-right "half-cup-shaped" zones of light are less natural to match for width than rectangular zones.

A square-cut rear notch OTOH seems to instantly and automatically center the front sight for me.

Each must decide for himself.

[El Cid]

I like the U notch for up close shooting at speed when using the front dot. For precision shooting with the top of the sights I don't notice any issues with the shape of the light. As for the history, the first time I recall seeing the U notch was associated with 10-8 about a decade ago. That doesn't mean they were first to do it. Just the first I remember.

[Street Survival]

U notch are cheaper to manufacture. I have tried both and tend to prefer the square notch like Warren Tactical.

[Dave J]

IIRC, one argument in favor of a U-notch is that it helps draw the eye to the top edge of the sight, rather than the bottom of the notch. I would presume that if you’re already well-conditioned to acquire the top edge, it probably doesn’t matter much.

Personally, I like U-notches, but only as long as they’re cut relatively deep, and still have a portion that’s flat and parallel. Shallow U-notches that are closer to half-round don’t work well for me.

[JV_]

When they first gained popularity, I had strong opinion about the U notch. Now, not so much. I don't even notice it anymore.

[Hambo]

Can anyone please provide some edumacation on the history of the U-notch rear sight?

Whose idea was it? Who was the first to prototype it? Who was the first to large scale market it? Have any studies been done on U-notch vs square notch rears?

I'm sure you mean recent history, but U shaped rear sight notches go back to the 19th century.

[GJM]

U notch are cheaper to manufacture. I have tried both and tend to prefer the square notch like Warren Tactical.

I thought Warren Tactical uses a U notch?