P320 X5 Legion, SRO without mounting plate

[Nord]

Since it may be hard to find info about thread sizes etc. I will post my findings here.

I have mounted a SRO without plate on my X5 Legion. According to some advice I found here at the forum it should be possible to avoid the empty case to hit the glass.

I did not succeed in avoiding that, even though I switched recoil spring, so I manufactured a homemade shroud from a piece of plastic from a concrete bucket. 

 

Having my shroud also protects the glass from powder gases and dirt.

 

In the processing of mounting my SRO I had to find out the following:

1. To remove the iron sight, I needed a 3/32 allen key.

2. To mount the SRO I needed screws 6-40 15/32 screws with T10 heads, and a T10 torx key.

3.  According to the SRO manual the SRO should be mounted with a torque of 1.7 Nm. I used 1.7 Nm.

4. I used a Dewalt T10 bit which looked like a spiral after applying a low torque at under 2 Nm, so choose your bit wisely. I succeded when I switched to a Bacho bit.

 

Some bonus info:

To remove the magwell  I needed a 5/64 allen key. By the way, my screwhead was damaged from factory, so be careful.

A new Sig 17 round mag will not fit with the magwell attached, but fits well when magwell is removed, see attached pic.

 

I epoxy bedded the mount to get rid of the gap in front and back of the sight. I only put JB Weld in the gap, not at the bottom of the mounting surface.

I roughly followed (425) Rifle Scope Base Bedding Part 1 - Gun Maintenance - YouTube

But since the geometry is a bitt different here, I did it in 2 steps. First back, then front. Also I waited for curing 8 hours before I removed the SRO.

I used car polish or masking tape on all surfaces I did not want the JB Weld to stick on.

 

The pictures are from before epoxy bedding, but a picture after bedding is not to exciting to look at. Hard to see any visual difference.

 

Edited December 19, 2020 by Nord
Adding some missing info

[B585]

Thanks for the information.    I haven’t seen much about this which is surprising given the popularity of both the SRO and the Legion. I was using I’ll play to mow mine, but I did not height over bore and have been looking for a solution.  I was waiting to hear from someone to find out if you could avoid brass striking the glass.  This may be the route I go.  Again, thanks for the information.

[matto6]

Sorry but I'm a bit confused.  You shoot with that extension duct taped onto the SRO and covering the ejection area?  

[Nord]

The shroud is not only duck-taped. I also use some other double sided tape.

It only covers the ejection area upwards, not anything to the right where the brass is going when ejected.

 

Anyway, it has worked great so far. I only had a few hundred rounds through my gun.

 

I will off course report back if I experience any problems.