Mounting BUIS on an offset rail.

[Mitch Rapp]

Anyone ever mounted BUIS on rails like this?

http://swfa.com/Weaver-Tactical-Offset-Rail-Adaptor-P46483.aspx

My AR has a full size scope on it, and I would like to be able to have a usable BUIS system for close range stuff. I could mount BUIS traditionaly but would have to remove the scope to mount them, or to use them.

 

[de-evoproject]

I've seen guys mount sights (never BUIS) and scopes on the sides of the rifle for different "tactical" reasons where they would have to turn the weapon sideways to fire it (Never bought into all that myself). The issue you run into with angled mount you are looking at is you are only TRULY sighted to 1 exact range.

With the iron sights directly on top of the weapon and zeroing at say 200m you know that if you can adjust for any range using simple mental calculations and only adjusting elevation, either by kentucky windage or actual sight adjustment (yes i know this is assuming absolute calm wind conditions and perfectly straight shooting rifle, I'm keeping it simple). This is due to the only adjustments being straight up-down and straight left-right.

Now with your proposed set up your adjustments are no longer in a "T" shape and are now in an "X" shape. Sure you could take the rifle out and sight them in to a certain range (through what i would think would be a complex and frustrating process). Any range variation tho are going to completely throw off your POI vs POA. Making windage and elavation changes are going to be near impossible in any kind of timely manner.

Also the angle at which you would have to hold your rifle to be able to utilize the sights so that they are adjusting on a nice vertical/horizontal, is going to be... uncomfortable to say the least.

I would highly recommend mounting the BUIS where they were intended to go and invest in a nice quick release scope mount and using your T marks.

 

[liliysdad]

I've seen guys mount sights (never BUIS) and scopes on the sides of the rifle for different "tactical" reasons where they would have to turn the weapon sideways to fire it (Never bought into all that myself). The issue you run into with angled mount you are looking at is you are only TRULY sighted to 1 exact range.

With the iron sights directly on top of the weapon and zeroing at say 200m you know that if you can adjust for any range using simple mental calculations and only adjusting elevation, either by kentucky windage or actual sight adjustment (yes i know this is assuming absolute calm wind conditions and perfectly straight shooting rifle, I'm keeping it simple). This is due to the only adjustments being straight up-down and straight left-right.

Now with your proposed set up your adjustments are no longer in a "T" shape and are now in an "X" shape. Sure you could take the rifle out and sight them in to a certain range (through what i would think would be a complex and frustrating process). Any range variation tho are going to completely throw off your POI vs POA. Making windage and elavation changes are going to be near impossible in any kind of timely manner.

Also the angle at which you would have to hold your rifle to be able to utilize the sights so that they are adjusting on a nice vertical/horizontal, is going to be... uncomfortable to say the least.

I would highly recommend mounting the BUIS where they were intended to go and invest in a nice quick release scope mount and using your T marks.

One really should have a concept of what he talking about, before doing so.

Nothing changes with BUIS or any other type of sighting device on a cant. The sight has no clue how its mounted, and neither does the rifle. When the gun is canted to use the sights, everything is the same, up to, and including, sighting it in. The only thing that changes is the way the gun is held. Up is still up, down is still down, etc.

 

[NikatKimber]

One really should have a concept of what he talking about, before doing so.

Nothing changes with BUIS or any other type of sighting device on a cant. The sight has no clue how its mounted, and neither does the rifle. When the gun is canted to use the sights, everything is the same, up to, and including, sighting it in. The only thing that changes is the way the gun is held. Up is still up, down is still down, etc.

Was going to say this, but you beat me to it. This is completely unlike a scope rotating in the rings, which would cause the issues mentioned.

 

[de-evoproject]

One really should have a concept of what he talking about, before doing so.

Nothing changes with BUIS or any other type of sighting device on a cant. The sight has no clue how its mounted, and neither does the rifle. When the gun is canted to use the sights, everything is the same, up to, and including, sighting it in. The only thing that changes is the way the gun is held. Up is still up, down is still down, etc.

I realize that. If you had read carefully you would have gathered that i mentioned holding the weapon on a cant to align the sights so that the elavation adjustment is straight up and down and windage is perfectly horizontal is not conducive to a good shooting form.

My reference to the adjustment axes being canted into an X shape was referencing he mounted the sights on a cant but did not cant the weapon.

One should really read before assuming another doesn't know what they are writing about.

 

[liliysdad]

That may very well be, but your bias against them uses negatives that exist only in your opinion. Many folks use these to great effect, and they work fine. The sighting axis argument is used time and time again, and it has exactly zero merit.

 

[Mitch Rapp]

I already cant the weapon for close range (under 75 ish) and sight down the side of the scope when speed is more important than precision. By this I mean shooting at the practical rifle match or things of that nature. I am looking to add more precision to my already standard practices. Thanks for your input so far, keep it coming.

 

[de-evoproject]

I already cant the weapon for close range (under 75 ish) and sight down the side of the scope when speed is more important than precision. By this I mean shooting at the practical rifle match or things of that nature. I am looking to add more precision to my already standard practices. Thanks for your input so far, keep it coming.

Sounds like a plan then. If you have no problems modifying your weapon position and are looking for more of a quick targeting solution than a max accuracy solution you should have no problems with the suggested set up.

 

[Wormydog1724]

http://harristacticalonline.com/product.sc?productId=216&categoryId=80

.

 

[Mitch Rapp]

Thats exactly what I want.....but $230!!! ouch