Longer screw for backsight Help needed

[Aussie Bruce]

I have a friend who has a custom revolver made from bits and pieces of different makes including a rear sight from a S & W
K frame. His problem is that it shoots low and the front sight cannot be lowered further. Is a longer rear sight adjustment screw available and if not does anyone know what thread is for this part? Thanks for your help

 

[littlerocknroller]

Longer Rear Sight Screw

Hello,
I don't think that a longer screw will do the job, because there is a limited amount of spring tension. I..e. - if you turn the screw out to the limit, there is no further "upward pressure" on the rear sight leaf. This part works like a long spring. Maybe you should try to find a S & W rear sight with a higher blade. These are different, depending on barrel length and model. You can also check www. brownells.com.
Good luck.
Rainer

 

[H Richard]

Your friend needs a taller "blade". It can be installed in the rear sight that he has, but will need to be able to determine what height he will need. He will need to know how much low it is shooting, and at what distance. Then what caliber he is shooting and how hot a load he intends to use. There is a mathematical formula that I can't lay my hands on presently, but probably someone else will respond. If not measure the total height of the present blade (gently screw it all the way out on one side for access to measure). Then with all the other information call S&W and tell them how much you need to move the POI up at what distance with what caliber and what height blade you presently have and they should be able to tell you what you need. The blade is relatively inexpensive and comes in a kit with instructions. READ the instructions, and when you go to break the screw and remove the blade I recommend you do it inside a clear plastic bag to keep from losing the detente and spring that will fly out.

 

[linde]

Your friend needs a taller "blade" . . . There is a mathematical formula that I can't lay my hands on presently, but probably someone else will respond . . .

There may be more complicated formulas that factor in muzzle velocity, bullet weight, barrel length, etc. but the most basic formula is that a .006" increase in rear sight height raises the point of impact 1" at 50 yards.

S&W blades come in standard heights of .106", .126", .146" and .160".

Good luck,

Russ