SGM Quad Rail for S12, need some help ours keeps coming loose/off

[tAKticool 0]

Hi all,

 

Brief background- Got my old man a S12 for Christmas , luckily bought it in early November before the madness. Has become somewhat of a project for us, he's put some dough and effort as have I... We're up to 17 magazines for it, I got a nice SGM Tactical 'Saber Boss' muzzle device, a SGM Quad Rail , and some Magpul fore grips (he chose the RVG rather than the AFG2 so I have the AFG2 for other use) ... Now the SGM Quad Rail ..

 

So I ordered it not realizing exactly what I was getting... Its a plastic forend with 'tri rail' sides /bottom and then it has a top cover 'rail' that screws on to make it a quad rail. There was no absolutely none instructions for installation, luckily it sort of just snapped together over the actual S12, then I screwed the top cover on , mounted the RVG foregrip, good to go.

 

Today taking it out, the thing lasted about 7-8 shots before coming off... I think we fired one 5 round magazine into the second 5 rounder and it came off. We spent the rest of the range time trying to get it to stay. it appears to have a little 'flange' or 'flap' of hard plastic that needs to 'insert' into the S12 receiver area but damned if I can get it in properly or to come all tightly together...

 

Any tips here, is there some instructions somewhere or something I am missing / need to do /not doing / etc.?

 

Thanks much in advance very appreciated. Not new to firearms but admittedly am new fairly new to the Saiga 12. (I am in NJ so we can't have converted ones , no semi auto shotguns with pistol grip, so its pretty standard as far as that goes).

 

Thanks again.