[Brick 2]

1. What is the standard height of the front sight blade?

2. What is the correct way to measure the height of the blade (from where to where)?

My Polytech shoots about 8" low at 100yrds with the rear sight set at the 100 yard mark. By my calculations, I need to mill about .050 off the top of the blade to get it to zero properly.


Brick

 

[ripsaw]

See if it is turned all the way down to bottom out first. If the sights are set properly, it will be about 8 clicks off bottom now to be on 100 mark. Front sight should be .062 high from the top of the sight base, at the back of the blade, not the front. They are tapered and will be shorter in the front.

 

[Ivan1GFP]

Hi Ripsaw,

I thought it was 8 clicks off the bottom for a M1 and 12 clicks for the M1A for a center hold at 100 yards.

- Ivan.

 

[levisdad]

.567"

 

[NoExpert]

Don't pay attention to the elevation marks, zero it, count the clicks and you can reset the knob to match the correct elevation when you're done.

 

[M1AallTheWay]

...My Polytech shoots about 8" low at 100yrds with the rear sight set at the 100 yard mark. By my calculations, I need to mill about .050 off the top of the blade to get it to zero properly...

As NoExpert says, start by zeroing the rifle. The elevation knob can be loosened and rotated to align the 100 yd mark with the line on the receiver after the elevation of the rear sight has been set in the zeroing process. This http://m14forum.com/reference/86160...ssembly-disassembly-adjustment-pic-heavy.html covers the entire disassembly/reassembly process but about two thirds of the way down you'll find illustrated instructions on how to set the elevation knob.

 

[brycom1]

Its not a matter of setting up the sights properly. The poly front sights are a lot taller than GI ones. I have been meaning to ask this question for a long time because my poly sights are the same way.


Thanks

 

[brycom1]

Just so you guys know my polytech front site measures .660"(Figure A of post #4)

 

[Brick 2]

I just measured my sight and it comes in at .586".

When I put the rear sight back together, I followed a link posted by someone else That said you were supposed to push the sight all the way down and install the geared arm so that the you could drop 2 clicks below the lowest mark, so to zero at 100 I had to move it up to about the 375 yard area.

Thanks for the answers guys.

Brick

 

[Ted Brown]

Zero

The normal practice is to set the rear sight to the desired number of clicks for the given range. If the rifle shoots high at this point, the front sight will need to be shortened. The rule is .008" = 1" at 100 yards. Once the sight shoots to the proper point with the desired number of clicks, the elevation pinion screw is loosened and the knob calibrated to the mark for the given range. As noted, some shooters don't bother with calibrating. They just count clicks.

 

[M1AallTheWay]

See if it is turned all the way down to bottom out first. If the sights are set properly, it will be about 8 clicks off bottom now to be on 100 mark...

The normal practice is to set the rear sight to the desired number of clicks for the given range...

Does this assume that the rear sight has the "100 yd zero aperture modification" described by Kuhnhausen?