Rear sight project

[sinnsyk]

I've done some machining on my newest Limited 40. I've opened up the rear notch width, lowered the notch and also lowered the top so it fits the IPSC with my biggest pads easier.

To say the least I'm not impressed by the factory adjustable sights, nor by another aftermarket 1911 brand sight I used and tested on my gun for about a year. So far, modifying the factory rear sight is the best option and I will do something to prevent the elevation screw from rotating during shooting.

If I get time, this week I will attempt to machine a fixed rear sight for my Limited. It'll be made to match up with the iFiber front sights. This means I will probably make a fixed rear competition grade sight for the Match as well.

Second part of this will be to possibly manufacture a robust adjustable rear sight. I've got some ideas, just have to see how I can get it done affordable. I'm tired of dealing with rear sights that re-adjusts themselves, pins move or break. I haven't completely broken many sights on my own, but I know of lot of other shooters who have.

For USPSA a fixed rear sight would be a perfect robust solution. For IPSC Standard we do need to be able to lower the rear sight to get high capacity base pads in the box.

[sinnsyk]

Here are some pictures of my modified factory rear sight. I did this for two reasons; 1) to get more width to pick up the front sight easier and 2) to be able to fit my gun in the IPSC box with my largest pad (H-570.. btw not available for sale at this point).

a) The rear notch was first lowered 0.060" as you can see how it digs into the bottom of the sight.

I then took 0.030" off the top to allow for 0.030" more room for a bigger base pad.

c) I widened the notch to 0.135" which gives more "light" on both sides of the front sight.

So far I like it a lot better. I've experimented with the depth and I will probably take another 0.010" off the top, leaving the so-far "final" depth at 0.120" vs the factory 0.100" (approx numbers as I'm sure factory measurements aren't always spot on).

When I cut the sight, I fixtured the upper in the vise so the all the cuts are trued to the sides of the slide. This makes for perfectly straight top line as well as notch cut. To no surprise, it cleaned up the sight picture as the factory sight was slightly 'crooked'.

On my older gun I've got a 0.120" deep notch which I like. During practice and the match this weekend I feel the 0.130" is too deep in combination with the iFiber which is 0.165". I'm also considering making an even taller front sight of either 0.175" or 0.180" and I'll just have to mount it to see which height will work the best. Seeing only the front sight and no part of the slide is a key in my book, but also seeing a taller sight should help. I'm doing this as I experience the effects in my shooting and trying to take it step by step.

I can see making a few fixed rear sights that gives me the visual feedback I'm looking for during very fast shooting.

As you can see from pics, I'm not running any dog-ears or reliefs on the sides. I've first stayed old school, but I can see some form of side relief happening in the nearest cuts..

Feedback, experiences etc are very welcome.

I ran 0.095" front with 0.135" rear and 0.130" deep notch at the Texas State Champs. I'll probably drop the notch to 0.120" depth and relieve the sides this week to see how I like it.

The nice thing is that I have another 2 brand new Limited 40's that I'm ready to cut the sights for and build up as complete guns. So I can play with a few different options on sights side-by-side.

Again, feedback and input can help shape things to come.. so any thoughts are welcome. Can't promise I'll make them that way, but I'll read the posts and take it all in. Also, if you have strong opinions just give me a call and tell me in person if you want.

[sinnsyk]

...and btw I will relieve the bottom more on the sides to allow for side-adjustment of the rear blade. The current cut doesn't do that. Just in case you wanted to point that out in a post.. I am aware of that fact ;-)

[Fudoshin]

I have been thinking a lot about the rear site on these guns. My site had the adjustment screw move clockwise (down) during the last Nationals here which was a bit disconcerting but once I was aware of it no real biggy, just meant I had to keep checking it. When I got home I sighted it in for 50m and took a note of where the notch lined up to. It has stayed ok for quite a few shoots and then moved down again last weekend. I would have thought it would move up. A friends rear site broke the rear blade off at the same Nationals (another .40 Limited HC) and when I saw how little meat there was actually holding this rear blade on by I have been worried mine might do the same thing.

I work in an engineering shop and have access to cnc mills etc and have been looking at making a fixed rear but soon realised that if I was to maintain the same point of aim I would just have a straight rear sight with no notch if it was still to fit in the box with your new magwell, 550 bases on mags, etc. The front sight is already pretty low so I don't think I can take any off that but have been toying with the idea of two side notches and having the front dot of the fibre optic foresite sitting proud on top of the central column in the rear site. It would look like the little i with a notch on either side of it.

At this stage it's just a thought and I'm not sure how fast it would be to get a site picture.

Another idea I thought might work was to just remake the pivoting part of the sight with no side adjustment, after measuring where mine is, and then just locktiting the height adjustment bolt in place. At least it would be a lot more robust!

Also been thinking about using fibre optic in a fixed rear site possible with the front site dot sitting on top of one in the rear site, or one on either side of the front site dot but lower down to give a upside down v shape. Again this would mean the rear blade could be lower than the front site with the front site dot just kissing the top of the rear site blade.

How was your point of aim affected by machining your rear site so low!

Edited July 21, 2010 by Fudoshin