I’m new to the forum, and don’t know how many 556 owners might be active, but I just got a 556 Patrol with the short forend, and would like to mount a vertical grip. There are three small holes on the under side of the grip, apparently for attaching a rail, but I haven’t found a rail where the holes matched. Any ideas on if/how this can be done? Thanks.

Pics please. The forum doesn’t host pics but if you go to postimages dot org you can upload a pic then by clicking on thumbnail for forums flag to the side and post it in a new post it’ll show up, and maybe we’ll be better help

If you are looking for the rail on the bottom of this photo B&T usa has a rail that will work in stock but its actually longer than you will need. You would have to dremel it to a shorter length to make it work.

Here is my B&T usa rail that I dremeled to make it work.



Here is a link to that part. https://bt-parts.com/bt-212117...rd/?searchid=2647419

You might also check gatewood supply from time to time to see if they get one in.

That B&T is made for the Swiss 551 handguard, not the P556 or 556 Patrol handguard which is Israeli--made.

What's needed is the SigSauer three rail kit no longer in production.

https://www.sigarms556.com/att...4f31a9453-jpeg.5479/

https://www.gunfactory.ch/lang...ccstgwsig_taktik.htm

Call Rolfe at gunfactory.ch he speaks english and they have the shorter rail in stock.

Thanks, all of you, for the information!!

The other option which I have done on another gun (NOT this one) is to buy a piece of rail blank and modify it to fit what you need. Rail blank is available in a bewildering range of sizes and shapes and perhaps one of them will approximate the factroy rail piece if you can't get that from gunfactory.

A typical noobie question is whether the holes in the handguard are pre-tapped, and if so, what thread screw would they take?

just holes. the factory set uses a nut to secure