Rear sight angle vs front sight post hight.

Most of my shooting is 10/12 meter target shooting.
Some time ago I noticed that, to get my sights properly adjusted, I had to turn the rear sight all the way down. By doing so the rear sight slightly leans backward (see picture 1 for reference)
The bottom of the notch in the rear sight is now not defined by the underside of the rear notch but by the top of the sight which give it a slightly blured picture as you look at rear sight at a slight angle (see picture 2)

As my eye sight is not as good as when I was 18, I need a as sharp sight picture as possible and have sufficient light between the front post and the rear sight notch.

The limited rear sight kept annoying me so I ordered 2 new front sight posts with 1 mm extra  height.
By using a 1 mm higher front post I have to raise the rear sight to get back on target and get back the complete notch depth and don't look at the top of the sight (the red area) any more.

Picture 1:Rear sight is slightly lower in rear

Picture 2:Red area is  what I see as bottom of rear sight notch

I ordered part no. Walther 2743774 and 2743778. Both are front sights with 1 mm added height.
After receiving them I compared them to my original front post and I found out that I Already have a 1 mm extra height front sight. Back to square one.
This was my fault, I did not know I had a 1 mm extra height front post.

Picture 3: 3 front posts, same height

I tried to ordered  Walther front post part no.: 2743776 (this post has 2 mm extra height) from a gun shop in Germany (from which I ordered the other 2) but they told me Walther doesn't have them anymore.  I contacted Krale schietsport in the Netherlands and to my surprise they had it in stock and I'm now waiting to get it in the post.In the mean time I cut off the head of a small carpenters nail and used it  as a shim under the front post, giving me the desired extra 1 mm. The small allen lock nut that holds the front post in the barrel holder does not fully engage the slot in the post (see picture 3) but is tight enough for the moment.

Arrow shows post now portruding 1 mm from barrel holder

I took it to the range this afternoon and sighted it in. As you can see the rear sight sits a lot higher now and is no loger leaning to the rear. I get a better sight picture.
(compare picture 1 with this one)


The SP20 RRS is a 25 meter rapid fire pistol. With my 10 meter sight setting the round come off 2 inches low at 25 meter, so the problem with my sights is not in the gun but in the fact that I shoot it mainly at 10 meters.

Several Hammerli SP20 videos

Videos collected on Youtube, videos are not made by me

Fully adjustable Pardini trigger mounted on SP20 RRS

With Pardini trigger in middle position

Stock trigger in most forward position

The standard SP20 trigger shoe is limited in its adjustability.
You can only slide it forward and backwards for about 1 cm.

Due to its rather big curvature it is impossible to move it forward enough if you have medium or long fingers.

The trigger slides in a U-shaped rail and is held in place by a 2.5 mm allen head bolt which screws into an square nut under the U-rail.

There is a flat Walther/Hammerli (part no.1301860 or 861, 862)  trigger available but I was unable to locate one.I also found an aftermarket trigger online that would suit my purpose, ordered it and received a stock trigger instead.

I looked at the Pardini trigger online and thought that this might be adaptable.

At first I considered making a small adaptor block which would sit in the original trigger rail and bolt the Pardini trigger to that block.

When I visited the gun shop and had a look at it and after some discussion I found out that it would basically be a drop in swap.

The distance between the rails (width of original trigger) was 6.2 mm, The Pardini mounting lug was 6.8. I filed  away some material on both sides and the job was done. (It took me less then 30 minutes)

The trigger is now adjustable in 3 axis. (forward/rearward, Up/down, left/right)

The up/down movement is limited but the adjustment range allows enough movement to centre my finger properly on the trigger.
If you look at the 2 pictures above and compare the red line you can see the improvement.

I made a  peculiar observation: After switching to the Pardini trigger the trigger pull dropped from 1200 to 1090 grams.  When I noticed this I switched back to the stock Hammerli trigger and it was back to 1200. Probably due to the fact that the Pardini trigger mounting bolt is now closer to the trigger pivot point. I did not measure it with the stock trigger in the most rearward position.

Pardini left, Stock Hammerli on the right

Hammerli underside, grip removed.
Shows trigger U-shaped sliding channel and square 2,5 mm mounting nut visible.

Hammerli part no.1301860  (I could not locate one)

Aftermarket Hammerli trigger