Author Topic: .45 Colt BC Sight  (Read 1964 times)

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Offline Big Blue

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.45 Colt BC Sight
« on: February 13, 2010, 07:43:15 AM »
I just added a Williams WGRS receiver sight to my BC carbine. I made a few measurements to try to determine the ideal front sight height and here they are. The barrel diameter at the rear sight is 1.1". I measured the height from the top of the barrel to the center of the WGRS sight allowing for it's adjustment range of .4" to .55" above the barrel and so figured the barrel radius of .505" plus the sight height of .4"-.55" and I'll need a front sight height to be between .905" and 1.055" or averaged to .980" as measured from the centerline of the bore to the center of the front sight's bead. The barrel diameter at the front sight is .7", so the radius is .35" and the distance from the top of the barrel to the center of the original front sight is .47", so I end up with a height of .82". To place the front sight in the middle of the rear sights adjustment range, the distance from the centerline of the bore to the center of the bead on the front sight should be .980" or .160" taller than the .820" I have now. Measured from the bottom of the dovetail, the original front sight is .570", the tallest offered be Williams. They do however sell a .250" riser which can be used to add height to the front sight. Given the need for .160" taller than the .570" sight, or .730" I believe the ideal front sight height used in combination with the .250" riser would be .480", but they are only available in either .450" or .500" so I'm thinking the riser plus the .450" sight would be my best bet.
Before I order anything however, I plan to shoot the rifle using the new WGRS sight with the original front sight just to see where the loads I'm using are going to hit.
Don   

Offline Mike in Virginia

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Re: .45 Colt BC Sight
« Reply #1 on: February 14, 2010, 04:15:19 AM »
Blue, I think your logic is right on target.  Yours is a good post.  It might be a good idea to save, because I'm sure the issue will come again, as popuplar as the BC45LC has become. 

Please let us know about that first range test, and then again if and when you change the height.  Thanks   Mike Gibbs

Offline Big Blue

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Re: .45 Colt BC Sight
« Reply #2 on: February 14, 2010, 05:29:38 AM »
Thanks Mike!

Offline quickdtoo

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Re: .45 Colt BC Sight
« Reply #3 on: February 14, 2010, 06:43:08 AM »
Thanks Don, I added it to the FAQs Sights section.  ;)

Tim
"Always do right, this will gratify some and astonish the rest" -  Mark Twain

Offline Doublebass73

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Re: .45 Colt BC Sight
« Reply #4 on: February 15, 2010, 05:47:04 AM »
Thanks for this info. Let us know how it shoots if you install it.
"Necessity is the plea for every infringement of human freedom. It is the argument of tyrants; it is the creed of slaves."

---- William Pitt (the Younger), Speech in the House of Commons, November 18, 1783