Where to mount a red dot sight on a pistol

When mounting a red dot sight to a rail on a pistol, are there any advantages in attaching it more towards the front, or more towards the rear?

Seems to me that the further towards the rear, the better, as it will make the gun feel "lighter".

Maybe it makes no practical difference, but in the photos I see of pistols with red dots, the sight usually is as far towards the rear as possible.

This photo is where I attached my Aimpoint H-2 on a High Standard X-Series.  
To me, it "looked" right, but maybe I'm missing something.

Nothing urgent, the gun seems to work fine as it is now, but if there's a good reason to move it, I'll do so.

......also.....  this rail is the one that came with the gun when I bought the gun from Alan.  But when I wanted to mount my Vortex Venom, it wouldn't fit the rail.  The slots are too narrow, and not deep enough.  I guess I need to order a different rail, or go to work with my file again, as I did years ago on another gun.  Not sure if the rail I have now is "Picatinny" or "Weaver".  My Aimpoint fits fine, but I wanted to try the Vortex Venom.

Most modern Dots either have a plate interface or use a Picatinny rail.  Contrary to popular belief, the Picatinny rail isn’t the same as Weaver.  Weaver rings wil work on a Pic rail, but Picatinny mounts often won’t work on a weaver base.

I mount the dot towards the rear so the weight is over the grip as much as possible.  When I mount it more towards the muzzle I can feel it in my forearm and tend to tire more quickly.  I guess I need to do some more weight training .

I can see where mounting it towards the muzzle could have some benefit in recovery after recoil.  I'm interested to hear what some of the more experienced shooters say.

Mike
All the pic rails I’ve seen, or own, have evenly spaced cross slots down the length of the rail. Weavers I’ve owned were all “odd” spacing. But the real diff is the slot width as Wobbly stated - roughly .2” vs .18”. Picatinny being wider slot.

Interestingly I have an Ultradot Pan AV that doesn’t fit a rail from Alan. It sits cattywompus. Almost as though the rail itself is dimensionally off. A the rings for a regular tube UD MD sit fine.

Well, during my range visit today, I was chatting with a shooter who is also a gunsmith.  He looked over my gun, put his thumb on the back of the (aluminum) rail, and he pushed it down.  It moves up and down.  

The whole rear part of this rail is over the slide, with no support.  Oops.
We moved it more towards the front of the gun.

I used to have a spare rail from Jon, but someone else needed it, so I sent it to him.
I guess I can keep things like they are now.
Wish I could try the Vortex Venom.

Most likely outcome is I will be buying another 1" Ultradot.  Need to check if there are any more for sale in this forum......

I found Amazon to have next-day-delivey for new 1" Ultradot.  Price was good.  
The (&%&(#! sight supports that came with the sight went into the garbage.
I used an existing pan of sigh supports that split horizontally, not vertically.
They are taller than I prefer.

Because of the very few slots on my almost-Weaver rail, there was only one place to most it.
See boring photo below.

I need to write Alan again - the slots on the rail are narrower than what Weaver rail slots are supposed to be, with might be the reason why the included mounts wouldn't drop down "into" the slots.   I expect to be posting my H-1 and H-2 Aimpoint sights in the for sale section.  I think Aimpoint sights are technically "better", but for me, the 1" Ultradot is better.

Rails:
Weaver mounting rails have slots that are .180” wide 
Picatinny slots are .206” wide.  


My rail slots are only 0.144" wide.


I need to write Alan again about this.


With a correct rail, the Vortex Venom sight "should have" fitted, as it supposedly works with Picatinny and Weaver rails.
Supposedly.   :-)

Mike, if you want to try a vortex venom shoot me a PM and I’ll be happy to loan you mine.  It’s just sitting in my safe. Also I’m in the hunt for an h1 or h2 so I’ll be looking for your classified!

Im also curious now about my rail from Alan. Going to measure it and report back.

Thank you RodJ.  Actually, I have two Vortex Venom sights, one of which I took off another gun (replacing with Ultradot) and one that I bought here in the forum for $130.  I've got a friend who might buy one, but I'll probably keep the other - I'd love to mount it to one of my other guns, maybe my Springfield 1911 9mm, but who knows.

Do measure your rail - you might find the same dimensions I did, which killed my thoughts of mounting the Venom - although I could file out the slot I guess......

As to the Aimpoint H-1, sure, figure out a fair price, and send me a PM.  I found a few, used, on a Google search, but I would never ask for that much $$$.  Tell me what you would be happy with.

As to the Aimpoint H-2, I may still have a use for it - need to compare the grouping I got from it on my X-Series with what I can do with my new Ultradot.  In every way I can think of, the Aimpoint sights "should" be better - better optics, and as I see it, much higher quality.  I can put it in the forum, but I'd rather sell it to someone who appreciates it the way I do.

Does your rail from Alan look like this?

I noticed a thread discussing mounting of red dots last week, that mentioned a mount made by Burris. I had just received an EGW mount, so decided to mount the EGW and order a Burris to compare. Here is the EGW with a DeltaPointPro on my Colt 9mm Trophy. I received the Burris mount this week, and mounted it to my Springfield MilSpec .45.
The Burris uses a small piece of steel designed to fit in the mortise of the GI fixed rear sight. It has two threaded holes that mate to the red dot plate, and when tightened, fix the mount in place. Luckily, Burris included two of everything in my package, because my first attempt at filing and placing the small piece of steel in the mortise deformed the screw holes, making them useless. My second attempt, I wised up and screwed the two mounting screws into the little piece of steel, before using my sight pusher to align the base of the mount to the mortise. 
The finished mount is sturdy and holds a Vortex Venom quite easily. I purchased this mount for $55 from Amazon, which is where the Burris sales link took me. It cost about the same as the EGW mount.
The EGW mount is rock solid. It required some file work and was installed using my MGW sight pusher in the vise. This mount was designed for the Bomar type slide cut, and the elevation screw was used to secure it, but the base is on the gun so tight, it wasn’t going anywhere even without the screw. I was surprised when the base actually aligned with the slide.
The steel used by EGW is far stronger than the Burris steel, which is Chineseum.
The Colt will evidently need more work than just the new fit bushing. It helped tighten the groups from the stock bushing, but so far the best groups are only achieved by the fastest loads.

Mike
My rail from Alan at Interarms looks like this.  The slots are narrower than Weaver and sloppy — 0.152” to as much as 0.160” wide and square in cross section.  The crappy vertical split rings on the UDMD still fit ok.  

But in third pic of the Interarms rail you can see that a UD Pan-A-V won’t sit properly.  The clamping side of the sight base is cattywompus (just below the ECI.  It’s as if the edges of the rail are too tall for the clamp.  This same sight locks down fine on my Ruger MKII weaver rail.  Oddly both rails have the same vertical dimensions and overall width of the rails (not the slot width) is the same or close. 

Understood - not sure what the problem with these rails is, but if I ever buy another from Alan, I will ask him to install a different rail.  No need for all this aggravation.

Thankfully, Aimpoint sights seem to work anyway, and my replacement sight mounts for my new 1" Ultradot - ditto.  Thanks for sharing the photos!

RodJ wrote:Mike
My rail from Alan at Interarms looks like this.  The slots are narrower than Weaver and sloppy — 0.152” to as much as 0.160” wide and square in cross section.  The crappy vertical split rings on the UDMD still fit ok.  

But in third pic of the Interarms rail you can see that a UD Pan-A-V won’t sit properly.  The clamping side of the sight base is cattywompus (just below the ECI.  It’s as if the edges of the rail are too tall for the clamp.  This same sight locks down fine on my Ruger MKII weaver rail.  Oddly both rails have the same vertical dimensions and overall width of the rails (not the slot width) is the same or close. 

Hiya,

The above pictures may be a mis-match of Weaver and Picatinny rails and rings. Mostly it's the depth (and with some rail brands the width) of the cross bolt slots to the centerline of the "V" of the rings that causes the issue. I've mounted Pic type rings to Weaver rails by milling the rail slots slightly wider and deeper. (Ultra dot rings to a vintage '80's NPC 1911 grip mount) and on the Pardini's milling the bottom part of the "V" off the rings so the point will engage the micro slot on the Pardini receiver.

There are 'Picatinny' rings on the market that are actually large 'dovetail' rings. They rest on the top of the rail, which is not a controlled surface by the Pic spec. Likely doesn't matter, but it'd be fun to make a rail with a bandsawed top face that meets spec just to mess with them. And they're not necessarily 'cheap' brands either.

I have several sets of Pic rings that fit a rail perfectly ... after I scraped the paint off of them. Otherwise they sit a little crooked, and make 3 lines of contact with the rail, bearing on paint ...

The bigger issue with them was alignment of the saddles with respect to the rail. Fine vertical, way off L/R. Reworked that as well.

I like them as they're quick release so I have the option of switching them between rifles. And they do repeat zero, at least on my rails, which are 'zero-zero' to spec, comp'd for hard coat.

I have some BAT rings that I like, and are really light. Unfortunately, they have double cross screws on the 10mm Pic spacing and won't fit some of the rails I have ... which includes the last gun I wanted to use them on.

The last set I bought are Leupold Back Country. Single screw, lightweight, and have a lug small enough to likely fit either rail ... other than the ones with round grooves.

Good comments and observations. What doesn’t make sense is that the UD PanAV fits the undersized cross slot on the Interarms rail. It’s only when tightening up the clamping adjustable side that the optic goes crooked. The same UD PanAV Fits the weaver rail on my Ruger.  

Next time I take the tube sight off the Ruger I’ll do some more studying to understand why the optic fits the Ruger rail but not the Interarms HS rail.

Likely not your issue, but I have *something* where the clamp plate looks symmetrical at first glance, but really isn't. And it sits crooked under the screw head if it's backwards. I wanna say it's a stamped part.

Like Wes, I have rings where the clamp blocks are not symmetrical as well.

You have to have them turned the right way in order for the rings to fit the rail properly.

Can't tell from the picture. Is there 'daylight' between the top face of the rail and the mount? Looks like maybe its tipped up from contact there, which would mess up the geometry of the clamp.

I can't see anything in the images that are posted as they are too dark to tell.

If the rings are not sitting straight on the rail rail, this is what I am referring to. The clamping block is not symmetrical. If it is upside down it may be the problem.



Your ring configuration may differ though!

I just observed at least 10 different Red Dots mounted on our rails at Camp Perry. They ALL had Weaver or Weaver Style Rings. NO problems mentioned by users or observed by me. We check our products with actual rings. Some of the pictures on this thread are NOT our mounts !!! Also, the "Weaver" style rings have threaded thru screws of varying size. I can NOT be totally sure from the pictures. We try to check everything BUT, we are NOT perfect. I would like to inspect any and ALL of the mounts that might be ours for any defects and function. - Alan Aronstein

My problem is simple.  This is probably one of the very first X-Series guns, which I bought as soon as it was available.
I sent all the following to Alan as an email a few hours ago.

• The standard groove specification for a Weaver rail is:  0.180”
  
• The rail my gun came with has a slot width of:  0.14”
  
  
• My Vortex Venom sight screw measures 0.159”
  
• This will fit a correctly sized Weaver rail, but not my rail.  
  
  
• I am in effect trying to push a 0.159” diameter “pin" into a 0.14” wide slot.
  

I need to add that I am VERY pleased with the X-Series gun.
My only issue is the rail.
With my new 1" Ultradot, all is well.
My Vortex Venom "pin" will not go into the slots on my rail.


The "junky" rail supports would not fit my rail.

I threw them out, and used after market risers which work fine, (but I want to replace with a shorter sight support).

My rail:

The High Standard Factory Bases have been made the same way since approx 1996. We have an aluminum  extrusion die that was made by a company near Dallas, TX that was recommended by Dan Bechtel( owner of B-Sguare Co). Richard L. was our Tool maker at the time. He made the tooling to cut the center recess, screw holes, and cross cuts in the extrusion. He made the tooling VERY close to the REAL USA Weaver Ring Set Measurements. The cross screw in the Weaver ring is approx  .140" and, it is flat on the bottom. Weaver Rings and accurate copies of those rings will fit our bases perfectly. Since 1996, I would guess that we have sold approx 10,000 of the bases in one or more forms. I think that  this might be the first time that I have heard about this issue. I guess that our bases might NOT work with some of the sights and rings that exist today. They can be individually modified to match those requirements by local gunsmiths or our gunsmiths can modify them for specific requirements.  - Alan Aronstein

I understand the history, but there is a specification for slots in a Weaver rail, and the slots in my rail are too small:

• The standard groove specification for a Weaver rail is:  0.18”
  
  
• The rail my gun came with has a slot width of:  0.14”
  
  

I think you should get all the rails machined to proper Weaver Spec.


I have no way to do this myself.


I do not have a "tight fit"; there is "no fit".  The parts will not go into the rail.  


These rails were said to be Weaver Rails (not Picattini), and they are defective, under-sized slots.


This is extremely frustrating.  Just look at the dimensions posted above.

I got an email from Alan.  Here's my reply:

Mike, 
 I have determined that our base is by design a tight fit for Weaver Factory or equivalent rings. Changes to the Weaver design by aftermarket suppliers is not an issue for us to address. Our base is designed to be a close fit for Weaver specs. After 28 years of manufacture  and approx 10,000 bases, it appears that we have TWO base fit  issues !!!  We or a local gunsmith can modify the base to fit the ring that you mention. I just got a HS Pistol for repair on Friday with an EGW Base and, I will check their slot dimensions. 

Alan - 
Thanks for the reply.  I expect that the other rail you just got back will have a 0.14 width slot, and it needs to be 0.18" width, (standard for Weaver).

It's not a "close fit", it's a "no fit".

Please do one more rail and send to me, and I will return the defective rail.

New Ultradot sights have risers that will NOT fit in the too-narrow slots.
New Vortex Venom sights - ditto.

     -Mike

Mike, 
First of all, our rails are NOT Defective. They are made to our specifications and they have been since 1996. They are made to TIGHT Tolerances which I feel is more important than trying to match every aftermarket ring specification.  The rail that you sent to me in one of your pictures is NOT even one of our rails. ALL of our rails have serrations in the center recess. The rails are bead blasted and have a Hard Coat Anodized Matte Black Finish. It would seem that we have sent out approx 9,998 rails with NO issue since 1996. I think that I sold over 30 rails at Camp Perry this year. They must have been OK-NO Returns !!!! I put a Holo-Sun(??) on one of them. It was OK. Again, your picture IS NOT our mount !!!!!
Maybe ALL of  the Red Dot companies should follow the Weaver Ring Screw Standard( which is .140"). or include their mount.  
  Alan

Alan,

Two quick things - the rail in my photo came on my gun.  I never removed it, and when I sent you my barrel a year or two ago, that's the rail that came on the gun

I have no ide whose rail it is - only that it was on my X-Series from the beginning.


I disagree with you - IF it is a Weaver rail, it is NOT up to spec - the slots are too narrow.

I think I got one of your first X-Series guns - I was waiting until they were available, you contacted me, and I bought it.

It was on the gun when I sent it back so you could replace the (also defective) magazine release, with one that worked properly.  Mine was too wide, and kept getting "loose" from the pins or whatever held it in place.  You told me I wouldn't be able to replace it, and I should send things back to you.  I also told you I thought the rear end of the barrel had a problem, as the "round hole" I expected was opened up at the bottom - I still have the photos I sent you.  And one more problem - when the gun was having problems, we discovered that the firing pin spring had broken into many pieces, so you had me send back the fragments of broken spring.

One by one, you've corrected all my problems, and now my X-Series is the best, or one of the best, 22 pistols I own.  It has shot the best target I've every gotten, from all/any of my other 22 pistols.   ....but this issue remains.  You can do as I did, look up the slot width specifications for a Weaver Rail"




The slots on my rail are too tight, so my sights don't fit.
Please exchange this rail with a correct size rail.