BR99 with T&N Forend Anti Rotation Pin

[ovenpaa]

A few of us have been experiencing problems with the after market Tooth & Nail Level 10 Forend rotating slightly in relation to the BR99 upper. The forend can rotate a few degrees left and right of centre when viewed along the longitudinal axis. In simpler terms if you have iron sights fitted they may cant to left or right destroying any chance of a decent and accurate sight picture.

Tooth & Nail as ever were quick to come to my assistance however this is not an issue they see in the USofA and their suspicion is the European BR99's have a slightly different barrel, receiver configuration so it is difficult for them to help without a Euro spec BR99 to work with. Apparently people slide HT O Rings over the barrel to act as a buffer and align the forend however this is not a perfect solution. Equally people fit Picatinny rail bridging pieces which looks hideous and effectively blot out the front sight when shot with irons.

My solution is to add a pin between the two Picattiny rails. The process is simple, drill and tap a hole central to the end of the rail, I opted for M5. then took a stainless M5 x 20 screw and machine 14,0mm of the thread to a diameter of 3,9mm. Drill an opposing 4,0mm hole in the other rail, screw and glue the pin in place and slide the two together.

You get a nice firm fit with zero rotation and the forend can be removed as normal without having to resort to any hand tools.

As ever the pictures are awful however this should give an idea of the fix, this was the first one I modified to prove the concept and the pin was replaced with something a bit shinier to finish the job off.

Camera glare allowing, you should get an idea of how the job is done. The shiny bit on the rail is not obvious to the eye and I took half a dozen pictures to try and loose it before giving up and just posting this...

[Dangermouse]

Looks like an obvious solution, most are once someone has thought of them!

DM

[Blackstuff]

Good work I think my BR99 will be off to the local gunsmiths this afternoon to see if he can do this before the next match, otherwise i'll have to stick with the bridge i'm using at the moment

[ovenpaa]

It is nice and simple and locks the front end very solidly, I have been asked about ways to align the pin to the opposing hole so this is what I wrote on my Journal:

http://shootingshed.co.uk/wp/2014/06/br ... ation-pin/

EDIT ) have been asked how I align the front and rear rail sections for drilling. I used an old woodworking technique. Make a shorter pin and machine or file it to a point and screw it in so it just stands proud of the front end of the receiver, now slide the forend into place and align it carefully with a steel rule on the side of the rail, if in doubt sight down the rail to ensure both sections are correctly aligned. Place a block of wood or similar at the front of the forend and give it a tap with a hammer and you should get a witness mark where the hole has to be drilled.

Job done!

[bofor]

Ovenpaa

Is the pin visible when the forend is fully on, as per your pic, or have you not fully mated them just for the pic demo ?

[ovenpaa]

John, there is a natural gap between the BR99 upper rail and the T&N forend rail so you see around 5,0mm of pin. I did consider painting the pin and even building a flat spacer however on this one it was left exposed.

[Blackstuff]

Well i skipped to my local gunsmith like a giddy school girl to get this done yesterday :shakeshout: , only to find out that my BR99 doesn't have anywhere near as tall picatinny rail over the recevier to safely do this Mine is at least 2-3mm thinner :roll:

On the plus side he's confident he's going to be able to machine a bushing that will attach to the inside/top of the forend to take up the slack and stop the rotation

[ovenpaa]

My hole sits nicely into the rail itself and I do wonder how many models/variants/versions of the BR99 there really are.

[Blackstuff]

In order to get a pin of that thickness in mine it would've had to go into the receiver, as well as the rail sign01

To go Alf Garnett for a minute, these bloody Turks wouldn't understand QC if it smashed them in the face with a German spanner :roll:

[ovenpaa]

I was very careful to keep the hole depth to a minimum and stay in the rail profile itself. The more I work with the BR99 the more I discover subtle and not so subtle differences along the way.