What is up with Rear Sight Forward (RSF) Slides and Sights?

Bobster

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I'm casually looking at an RSF slide from PSA LINK. I've seen a few more of this style in different variations. As I've become more vintage, I've been wondering if it is time to get a pistol with a red dot for my seasoned eyes.

I know about the different optic mounting patterns and so on (ie: RMR, etc.), but do I want RSF or RSR (Rear Sight Rear)? The RSF looks dorky to me but I'm more of a function kind of guy so how do they work? I assume the reasoning is to get the dot sight further back and closer to the eyes? :unsure:

But I'm curious how the included 1/3 co-witness tall sights appear through the dot sight. Do they look better before or after? Anyone have a link of a comparison?

I don't know if the slide linked and pictured is for me--I'm more looking for more "normal" without all the cut outs unless they are functional (ie: ported barrel). I don't know if I want to pay extra for a threaded barrel, either at least not for a carry build...

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The RSF looks dorky to me but I'm more of a function kind of guy so how do they work? I assume the reasoning is to get the dot sight further back and closer to the eyes?

I agree. The esthetics of the "RSF" do not appeal to me... at all. I think the idea is that it doesn't seem to clutter the optic window as much. Optical illusion (pun intended), of course.

I think it comes to personal preference.

Me? I don't see the need for "back-up" sights in any case. The reality is that if it's a range toy, who cares if the battery goes dead? If it's a carry or defensive piece, then just change the battery once a year like you would your smoke detectors. The possibility of a battery going dead unexpectedly is nearly zero.

I have a future build intended for range duty only that I'd like to not use iron sights at all. The trick is doing something with the slots milled into the slide for those iron sights. I found a blank plug for the front sight hole. But I have not been able to source a rear sight dovetail plug (that would be flush with the slide).
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I don't see the need for "back-up" sights in any case.
I hear that! I'm kinda like Elmer only there would be a cigar in my mouth... :D

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I have a future build intended for range duty only that I'd like to not use iron sights at all...But I have not been able to source a rear sight dovetail plug (that would be flush with the slide).

Nice looking slide! :) I almost picked something similar up from ZP over the holidays (ie: BF deal). Around $400 for a 19L slide/ported barrel combo. I wasn't sure if I wanted a 34 size setup so it would fit in the "box" but wasn't crazy about those styles (ie: a little too blingy). What size is yours?

PS: regarding the "rear sight dovetail plug" what if you just ground down an old sight? Or like a G20/G21 sight which might be wider?

Regarding my original question, I have not found much info or more specifically, pics. The first pic is an adapter plate with a RSF sight "built-in" but no front sight shown. The second pic is a view of a RSR setup on a G34.

rsfview.jpg rsrg34.jpg
 
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Nice looking slide! :) I almost picked something similar up from ZP over the holidays (ie: BF deal). Around $400 for a 19L slide/ported barrel combo. I wasn't sure if I wanted a 34 size setup so it would fit in the "box" but wasn't crazy about those styles (ie: a little too blingy). What size is yours?
I liked the two-tone brushed metal / cerakote look. It's a G17L (long slide). Even longer than a G34.

PS: regarding the "rear sight dovetail plug" what if you just ground down an old sight?
That's what I've thought about doing. Just grinding down a factory steel rear sight.
 
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"Do you guys prefer lower 1/3 co-withness commonly found on PSA?"

Similar question was asked on Reddit. Has very nice picture to compares.

This was my comment:

Range toy - no irons, running just dot. Carry - 1/3 co-withness. Absolute co-withness... the dumbest idea for the red dot, your blocking 50% of the window and your not going to see the iron when the threat focus... don't do it, unless u got a can.


View: https://www.reddit.com/r/PalmettoStateArms/comments/13gkruc/no_cowitness_vs_lower_13/?utm_source=share&utm_medium=android_app&utm_name=androidcss&utm_term=1&utm_content=share_button
 
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As for optic front vs rear of iron sight. It is personal preference just like asking which trigger do you like.

I have both and practices with both. When using dot, I don't even see the iron sights anymore.

If your new to optics few important concepts to consider.

  • Optic become your primary sight. Thus, which iron to use becomes less important. (ie how often do you use backup iron on rifle these day?)
  • Finding the dot consistaintly become more important, need ton of dry fire.
  • Primary benefit of using optic is target forcus. Your supposed to look thur the dot and focu on the target. May also need to dry fire ton if ur natually forcus on front sight.
I'm sure I missed few more points. So yea optics is far superior sights.
 
Primary benefit of using optic is target forcus. Your supposed to look thur the dot and focu on the target. May also need to dry fire ton if ur natually forcus on front sight.

Both eyes open helps and is even more important with an optic.

Another (unexpected for me) benefit of an optic is that it's FAR easier to "call your shot." In other words, it's easier to diagnose why your shot went low, because you'll see the optic dot dive down. Seeing that with iron sights is a challenge. But it's obvious with a dot. If it's easier to diagnose your bad habits, it's easier to fix them.
 
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I've been adding threaded barrels to all new handguns, thus tall sights. I use a can frequently. I agree with @Racer88 that co-witness sights are marginally useful. Not useless, but marginal. Red dot optics are pretty reliable. I'd put money on an FTF being more likely than an optic failing at a critical moment.

I have a couple of recently built pistols with the RSF. I bought the slides that way just to give it a try. I don't feel like it interferes with the RDS. But that could depend on which RDS one chooses. Very small window? Possible the taller sight might block some of it.

I was an early adopter of red dot optics and I like them. On the range it improves your accuracy at 50 yards and depending on your fundamental shooting skill perhaps closer in as well. In numerous self defense scenarios, I question the value of a red dot with one exception... needing to take a longer shot and having the time to do so.

My opinion is a red dot makes no one faster. Even in competition it will improve accuracy but not your times, which factor prominently in your score if you are in a defensive shooting, IDPA match. I have yet to see anyone improve their actual time because of an optic. But as some already know, you get points down (and this time added to your score) for poor accuracy, and for penalties. Kind of like how strokes are added to your golf game when you lose a ball. Poor accuracy involves a time penalty. It's important to not confuse this with actual (elapsed) time between rounds... which includes acquiring the target and pulling the trigger.

When an armed thug threatens you at the 7-11 market while buying a Big Gulp and a Twinkie, a red dot is useless. You draw and fire in less than two seconds. Or suffer the consequences of being too slow. Under duress, you are going to point, not aim. In order to point you need that front sight reference. Rear sight... also pretty useless in that situation.

So what does that have to do with taller sights or the rear sight moved forward? Nothing. It doesn't help, it doesn't hurt. It's a big nothing burger. Some may like it and others may not. The horizontal position of the rear sight within your sight picture makes no difference at all. If the sight is too tall for the optic chosen, it's too tall no matter where it's installed. Moving it forward or leaving it in the traditional position doesnt change anything.

I'll end the sermon by suggesting that if those really small pistol optics are a preference, then don't combine them with tall sights. Go with the biggest window you can get. Trijicon, Leupold, Metro, CT, Viridian, a few others.
 
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I personally prefer the suppressor height sight in front of the optic. However, like mooner stated the sight is there but is ignored as the optic is the focus. The iron sight is merely there as back up.

With the sight behind the optic it’s in the way, it blocks the optic. No purpose to have an optic if your using the iron sights
 
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My FNP-45T came with a threaded barrel and therefore suppressor height iron sights. Since it was also milled for an optic, I bought "the best" at the time... the Trijicon RMR.
FNP-45T-Home-Defense.jpg


As you can see in the photo, between the tall iron sights and the small window of the optic, there is very little "visual real estate" through the optic. Hell... if it wasn't for that adapter plate, the optic would sit lower, rendering even less visual real estate with the irons being relatively higher.
FNP-45T-RMR_0008.jpg
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Compare that to my PFC9 with "mid-height" iron sights and the Holosun 507:
PFC9-with-Holosun-507C-ACSS.jpg
 
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I don't think we'll see iron sights completely disappearing as a sighting option, but I do think the industry will migrate to slides being milled either for irons or RDS, opposed to the currently common combination. This especially so as the size and price of enclosed emitters begin decreasing.

Once one learns to use RDS, "co-witnessing" really makes no sense to me.

I am also looking for a solution to plug the sight ports for an RDS slide, and am also considering either having my G23 slide milled, or buying an additional with no sight ports milled in. I've also considered cutting down an old set of sights, and this may ultimately be the route I end up with. I'm really surprised, though, that the 3D printers haven't yet modified a sight program to make the relevant sight port plugs.

I have rifles with no BUIS, and for a myriad of reasons I am both happy and confident now of an RDS-only sighting option on a carry gun. This is how I will proceed into the future.
 
When an armed thug threatens you at the 7-11 market while buying a Big Gulp and a Twinkie, a red dot is useless. You draw and fire in less than two seconds. Or suffer the consequences of being too slow. Under duress, you are going to point, not aim. In order to point you need that front sight reference. Rear sight... also pretty useless in that situation.
Agreed
 
Once one learns to use RDS, "co-witnessing" really makes no sense to me.
Yep. I have not ever run into a situation where I needed to "co-witness" or use the back-up sights. And I can predict I never will.

I have rifles with no BUIS, and for a myriad of reasons I am both happy and confident now of an RDS-only sighting option on a carry gun. This is how I will proceed into the future.
I will still have iron sights on any carry pistol even with an optic.... for well... the LEGAL "optics."

When an armed thug threatens you at the 7-11 market while buying a Big Gulp and a Twinkie, a red dot is useless. You draw and fire in less than two seconds.

True. I won't be using the optic at such close quarters defensive situations. But similarly, I also wouldn't be using iron sights. So that (rather popular) argument against optics falls flat... because it also negates the value of iron sights in THAT situation.

That all said... there has been a coordinated effort by the training community to decry instinctive / point shooting training. And I mean a STRONG objection to it.

But here's the thing... Having an optic and / or iron sights on the pistol when shooting instinctively (aka "point shooting") is not detrimental. I went through a full-day instinctive shooting course with my optic-equipped EDC pistol and never used sights at all. Prior to that, I took a 2-day instinctive shooting course with a pistol equipped only with irons. Didn't use them once. But in all cases, neither the optic nor the irons were "in the way." They were not detrimental. And if the fight ends up being at a longer distance (see Eli Dicken at the Indiana mall), I'd rather have sights... more specifically (and lately) an optic works better for me.

And if the fight is a combination of close and far distances, I can remain "threat focused" for BOTH instinctive AND sighted fire with the optic. Can't do that with irons.
 
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As you can see in the photo, between the tall iron sights and the small window of the optic, there is very little "visual real estate" through the optic. Hell... if it wasn't for that adapter plate, the optic would sit lower, rendering even less visual real estate with the irons being relatively higher.
Yep, Exactly one of the reasons I pointed out why I prefer for having the optic behind the sights. They block the optic. 😊. Nice picture showing the issue. 👍🏻

When an armed thug threatens you at the 7-11 market while buying a Big Gulp and a Twinkie, a red dot is useless. You draw and fire in less than two seconds. Or suffer the consequences of being too slow. Under duress, you are going to point, not aim. In order to point you need that front sight reference. Rear sight... also pretty useless in that situation.
Ok, so let’s not put any sights on our fire arms cuz they are of no use. 😝. I’m curious if LE and operator community would agree with this statement. Any LEO around care to opine on this?
 
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I shoot with both eyes open when shooting close up, so I don't even see the sites. On my conceal carry I just have small iron sites. On my range pistols I have red dots on most of them with co-witness sites but again never really see them.

I have wondered what the advantage in sites in front of red dot is over behind red dot, I don't really understand it other than a different look.

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This is the only pistol I have with sites in front of the red dot and when shooting I just don't notice them at all. These are suppressor height sites from Steel City. I will be building a couple of target pistols this coming winter and I think I am going to do the ground down site blanks, just using a red dot.
 
That all said... there has been a coordinated effort by the training community to decry instinctive / point shooting training. And I mean a STRONG objection to it.
That is true. I suspect led mostly by people who have never been in a gunfight. Like the 60-something fat guy at an IDPA match who knows the answer to everything. Imagines himself as a Yogi of gunfighting. Or perhaps a Yoda. :)

In any 'sporting' endeavor, there are always a vocal group who try to make a science out of everything. Allow me to wax on this to make my point about not following what self-appointed pundits tell us is best.

I played organized league baseball all my life from age 8 to high school and college. I also played what's called 'legion ball', which has been round since the 20's and half the American born Major league players were part of. I was pretty good. Sadly, not good enough to get picked up by a scout, but better than average. No regrets. The happiest days of my life were on a baseball diamond.

My HS varsity baseball coach was convinced that if you could run fast, you would be a better baseball player. Instead of devoting all of our time to practicing hitting, pitching and fielding, he had us running half the time. The guy was a f__ing idiot who never actually played the game. So at 17, I quit the HS team and played Legion ball, which you can do until you re 19. There were kids (ok, young men) who were throwing heat like the guys in the big show. 90+ MPH fastballs. Nothing like the high school teams I had become accustomed to. It made me a better player. Because there was no moron coach telling me that running fast is more important than hitting a baseball coming at you at 90 MPH. Those who can only run fast never get to steal a base - because they strike out.

In a similar vein, the quickest way to lose money is listen to advice from stock market analysts. People who really know how to make money investing don't waste a minute of their day telling other people how to make money. :)
 
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Somebody explain to me how this is a problem. I'm a little slow.

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Thank you all for your input and pics! (y) It has been most enlightening.

Just recently I have had a renewed interest in getting a RDS pistol. A property sale has given me a little "extra" money to play with. Although I bought a couple P80 frames "just to have", of course I got to thinking about a slide to put on them. :rolleyes:

I get PSA's email "flyer" and noticed they had a little Holosun 407 RMR-pattern for $180 after coupon. Not wanting to spend money on a sight that will just sit, I also looked into a slide from them to put it on. Dragged my feet and missed out on this slide for $210. :( And the sight is now back up to $200 after coupon. :(

holosun.png soldoutslide.jpg

Then the FDE slide I posted above came up on sale, hence my initial question about RSF or RSR. And now you have me thinking about no sights at all! :D The following is PSA's current "slide of the day" for $260. Although handsome, I don't think it is $60 handsome! I'm more into a plain, solid color slide with regular-length black or silver barrel and optics cut-out with sights that can be used until an RDS is acquired or if the RDS is moved to another gun. The more I thought about it, the more the RSF sights seemed silly and would have a very small sight radius without a RDS.

flagslide.jpg

As mentioned, co-witness sights might obstruct the view or be superfluous with a RDS... I kind of like the 1/3 co-witness sights as a compromise as in visible though the RDS and not too monstrously high without RDS. I don't have immediate plans to get a can so a threaded barrel or super tall sights are not needed. I DO like the way the threaded barrel adds a 1/2" to barrel length perhaps making it more accurate? ;)

This is the "box" I mentioned above. The G34 fits in the box while the 19L does not...
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These sights are on debay. LINK I got a similar set in black a year ago for $20 so the price has come down. You will need a toothpick with a dab of paint to color the little circular recesses in them or just leave them solid. Or grind them down for a dovetail filler... ;)

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Yep, Exactly one of the reasons I pointed out why I prefer for having the optic behind the sights. They block the optic. 😊. Nice picture showing the issue. 👍🏻
It will block the same amount of real estate in the front... but it may be argued that it's less mentally distracting. Putting it up front doesn't make it smaller.

Ok, so let’s not put any sights on our fire arms cuz they are of no use. 😝. I’m curious if LE and operator community would agree with this statement. Any LEO around care to opine on this?
I don't think he's saying that (no sights at all). He's making the point that iron sights that are "co-witnessed" don't make a lot of sense, since the chances of actually using them that way are nearly nil.

And I agree, based on my usage of optics so far. And logically... the "battery going dead" is a non-issue, if you are diligent about replacing the battery on a regular basis BEFORE it's lifespan is expired. Even our own USMC use a battery powered optic on their service rifles now.
 
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