Foresight inserts for a FWB 601

szumi · Post by **szumi** » Thu Jan 19, 2012 3:29 pm

I just received a FWB 601 which came with one sight insert. I'm trying to learn a bit about the sight. It looks like you can install inserts from front and back and it is also slotted like a drop in insert could be used.

I'm a dummy at this. Where do I get inserts, will the stock sight also take post inserts, what do I ask for, ect?

Help educate me,

Szumi

justadude · Post by **justadude** » Thu Jan 19, 2012 4:23 pm

Measure the diameter of your existing insert. If it is 18mm or just a hair over 11/16 of an inch you have the 18mm front sight. This was most common for the 601 although I hear there are a few of the early models with the 16mm front. For now, I will assume the M18 front sight.

Pretty much any of the clear plastic inserts made for 18mm front sights will work. Additionally, if you want to go this route, the adjustable front apertures set up again for the M18 thread will screw right in.

From manufacturer to manufacturer the ears that help lock the metal inserts into the front sight tunnel can vary so if you want a post insert you will need to specify it is for a FWB front sight.

As far as the removable ring on the front, you could if you had the right size and wanted, put a colored filter in there or if the competition allowed for it a lens.

'Dude

szumi · Post by **szumi** » Fri Jan 20, 2012 4:33 pm

Okay, I figured out by measuring the two threaded bushings that it is M18. I'm guessing any plastic insert that is 18mm will work. I'm wondering if Anschutz metal inserts will also fit.

Szumi

GaryN · Post by **GaryN** » Fri Jan 20, 2012 5:18 pm

Try it and see.
While the diameter might fit, it is the tabs/ears that might be different from brand to brand.

nester · Post by **nester** » Fri Jan 20, 2012 5:48 pm

Here is the standard Anschutz metal insert over the 1mm grid - you can measure yours and compare:

szumi · Post by **szumi** » Fri Jan 20, 2012 6:02 pm

I ordered a selection of clear aperture inserts from Champions Shooters supply and one Anschutz metal post insert to check if it is a fit.

I have a .22 rf that uses a Williams aperture sight. The foresight is threaded M18 and I can screw the bushings from my 601 into my Williams and the other way around.

The stamped metal inserts for the Williams sight don't index properly in my 601s foresight though.

I'll know more when I get my order.

Thanks for the help all.

Szumi

szumi · Post by **szumi** » Wed Jan 25, 2012 6:20 pm

The clear inserts came in and have a single OD. The major diameter is right but my single insert has two diameters. My googling has me believing that this is refered to 17/15 mm. The actual measurements .121" or 3.07MM thick, D1 = .676" or 17.17MM, D2=.598" or 15.19MM.

There is a plastic collet style ring that screws into my front sight that indexes on the D2 diameter. The clear inserts are a bit thinner but I could machine a shallower D2 diameter using my lathe and an emergency collet.

The Anschutz metal insert does not index with the two drilled holes and is unusable.

I'll try to take pictures this weekend to help clarify what I'm working with.

Szumi