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Glock 48 MOS and Co-Witness BUIS

Ranger007

Sergeant of the Hide
Full Member
Minuteman
Feb 7, 2021
101
67
Behind Enemy Lines
Greetings,

Curious if anyone is running a G 48MOS with Holosun 507k and C&H plate and what BUIS you are running to co-witness?
 
Do not co-witness buis on a RDS handgun is takes up to much of the window space and doesn’t provide you with any benefits.
Valid point and I am tracking.

My intended use is its going to be my primary conceal carry. I am runing RDS on some of my competition pistols with co-witness BUIS and I like it, for me it works. I am by no means a serious competitor. I am aware that its repetitive training to put the optic on target and its quicker than putting the front sight on target. Problem is I am not quite there to put 100% of my trust in finding and putting the dot on target and that its another potential point of failure and if it does fail I can have an option to put the BUIS on target. Hope that makes sense?
 
Valid point and I am tracking.

My intended use is its going to be my primary conceal carry. I am runing RDS on some of my competition pistols with co-witness BUIS and I like it, for me it works. I am by no means a serious competitor. I am aware that its repetitive training to put the optic on target and its quicker than putting the front sight on target. Problem is I am not quite there to put 100% of my trust in finding and putting the dot on target and that its another potential point of failure and if it does fail I can have an option to put the BUIS on target. Hope that makes sense?
Understandable. When I first set up my pistol with an RDS I had co-witnessed buis. Never thought much about it and just worked with it. This summer I hosted a Modern Samurai Project RDS class. After talking with AJ and shooting a couple other pistols with lower buis I took my irons off the gun until I could get some lower height ones. I did a lot of dry fire after the class while waiting for my sights to show up, and I will tell you that I’d never go back the co-witnessed sights.
 
Valid point and I am tracking.

My intended use is its going to be my primary conceal carry. I am runing RDS on some of my competition pistols with co-witness BUIS and I like it, for me it works. I am by no means a serious competitor. I am aware that its repetitive training to put the optic on target and its quicker than putting the front sight on target. Problem is I am not quite there to put 100% of my trust in finding and putting the dot on target and that its another potential point of failure and if it does fail I can have an option to put the BUIS on target. Hope that makes sense?
I'm a relatively serious (as in I work to be as good as I can be) and decent enough (A class) USPSA Carry Optics competitor. None of my match pistols have sights that are tall enough to see through the glass. I have zero trouble drawing to any target, no matter how awkward it is, and having the dot show up on target.

How did I do that? Through thoughtful, honest self critique of my draw and by fixing it through disciplined dry fire.

You need to abandon the derp idea that you're going to use the BUIS to find the dot when it doesn't immediately appear at the end of the draw. You need to fix your draw and your index until the dot appears where you look 100% of the time freestyle, strong hand, and weak hand. If you won't commit to that, just take off the dot and sell it because you'll never realize its potential.

What if the dot dies? Have you ever tried shooting with it off? I have and what I found is that I can make guaranteed A zone hits at up to 10 yards running .3 splits, and out to 15 yards running .4 to .45 splits by framing the target in the empty window of the sight. I have shot out to 30 yards that way to see what would happen and accuracy falls off quick past 15. I'm ok with that. Id have a hard time justifying a self defense shooting that far away. In any case, using quality sights (Trijicon) means that the issue is even less likely than me needing to shoot someone. One caveat, this works well only if your grip and your index (index meaning the pistol goes to where you look without having to refer to any sights) are sorted out. IMO, index is just as much of a fundamental skill as a clean trigger press and a grip that lets the pistol recoil controllably and repeatably.

Only one of my pistols has BUIS and that's because I didn't know better 2 years ago. They're likely coming off.

And stop trying focus on the dot itself.
 
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Understandable. When I first set up my pistol with an RDS I had co-witnessed buis. Never thought much about it and just worked with it. This summer I hosted a Modern Samurai Project RDS class. After talking with AJ and shooting a couple other pistols with lower buis I took my irons off the gun until I could get some lower height ones. I did a lot of dry fire after the class while waiting for my sights to show up, and I will tell you that I’d never go back the co-witnessed sights.
I'm a relatively serious (as in I work to be as good as I can be) and decent enough (A class) USPSA Carry Optics competitor. None of my match pistols have sights that are tall enough to see through the glass. I have zero trouble drawing to any target, no matter how awkward it is, and having the dot show up on target.

How did I do that? Through thoughtful, honest self critique of my draw and by fixing it through disciplined dry fire.

You need to abandon the derp idea that you're going to use the BUIS to find the dot when it doesn't immediately appear at the end of the draw. You need to fix your draw and your index until the dot appears where you look 100% of the time freestyle, strong hand, and weak hand. If you won't commit to that, just take off the dot and sell it because you'll never realize its potential.

What if the dot dies? Have you ever tried shooting with it off? I have and what I found is that I can make guaranteed A zone hits at up to 10 yards running .3 splits, and out to 15 yards running .4 to .45 splits by framing the target in the empty window of the sight. I have shot out to 30 yards that way to see what would happen and accuracy falls off quick past 15. I'm ok with that. Id have a hard time justifying a self defense shooting that far away. In any case, using quality sights (Trijicon) means that the issue is even less likely than me needing to shoot someone. One caveat, this works well only if your grip and your index (index meaning the pistol goes to where you look without having to refer to any sights) are sorted out. IMO, index is just as much of a fundamental skill as a clean trigger press and a grip that lets the pistol recoil controllably and repeatably.

Only one of my pistols has BUIS and that's because I didn't know better 2 years ago. They're likely coming off.

And stop trying focus on the dot itself.
Thank you both very much, excellent discussion!! I’d be lying if I said I have not heard this before by instructors from a few of the classes/training I have attended recently.
I have spent decades shooting and training with iron sights. I am going to attend a few more classes and continue training with RDS.

Massad does a great job explaining this as well.

 
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Thank you both very much, excellent discussion!! I’d be lying if I said I have not heard this before by instructors from a few of the classes/training I have attended recently.
I have spent decades shooting and training with iron sights. I am going to attend a few more classes and continue training with RDS.

Massad does a great job explaining this as well.



I'm afraid to watch his video for fear of hearing a bunch of fuddery but I will repress my prejudice and watch it later.

In the interest of full disclosure, I don't idolize any "instructor" or "subject matter expert". Massad Ayoob is definitely an expert in many areas, and while he might be competent with an RDS on a pistol, I doubt he has the specific expertise that Scott Jedlinski or Hwansik Kim do.

I think training classes are overrated to be completely honest. If all you need is to unlearn front sight focus and learn target focus, place a piece of opaque tape over the front of the RDS lens and start dry fire training. You will find out that it's impossible to see the target and the dot at the same time unless both your eyes are focused on the target. It's how human vision works.

The other major mistake iron sight shooters seem to make is to overconfirm the shit out of the sight picture. An RDS on a pistol will show you all the movement that has always been there but you couldn't perceived through iron sights. That paralyzes some people into trying to make the dot be as still as they think their irons sights were and it results in being painfully slow and sometimes leads to snatching the trigger. Along the same lines, you will need to learn how to "shoot the streak of red" if you want to be able to rip fast (sub .25) splits.

The good thing is that a red dot sight gives you so much more feedback that you can use to self diagnose and fix a lot of problems. My ability and confidence to shoot on the move skyrocketed after I got used to a red dot, and most of that training happened without firing a single shot.
 
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