Rail Installation

  • I have been shooting my 513 a lot lately and finally purchased an Atlas bipod. It was an injustice to mount it on a sling stud adapter so I decided to put a rail section on the bottom of the stock. The GI issue stock has a plate recessed into the fore end with numerous threaded holes to enable the shooter to get a sling positioned for shooting. I was hoping the holes would be the same centers as a Key Mod rail section and there wouldn't be any problem attaching the rail to the original plate. Well, dream on not even close and they were some weird thread anyway ( 48 tpi ) so I made a new plate from aluminum. For some unknown reason the plate dimensions were 1/4" thick but .560 wide. I had 1/4 x 1/2 plate but it would have made a nasty gap in the recess of the stock so I had to machine a piece out of 1/4 x 1 inch aluminum to .560 wide. Without a milling machine it was done in the lathe after trimming it down in a band saw. The rest of the shape and mounting holes were traced and drilled in a standard drill press and radiused on a belt sander. The rail mounting screws are 8-32 I tapped in the drill press also. I'm not 100% sure they were 8-32 but the screws provided with the rails fit I would have figured metric. Made a good foundation for the bipod when it was done. Mounting a rail section on the bottom of a stock isn't too big of an operation and can be done with a hand drill. The makers of Atlas bipods sells rails that utilize the existing sling stud hole and has a slot for the back hole to make it easy to drill and get it straight. I have several other rifles I want to do this but only have keymod rail sections so hitting the hole centers is crucial. For the money the Atlas rails would be worth it might save some aggravation. Some other suppliers sell them also. I got a blurry picture in there, sorry.

  • The rail and fasteners from BT are only 25 bucks plus shipping and have a curved back for stocks that aren't flat. I will probably be ordering some of these most of the stocks I have are slightly curved and the Key Mod rails are flat. If I was to have a custom rifle and stock combination I would want a fastening system built into the stock more than likely M Lok so accessories could be attached.

  • @bigfoot

    Atlas rails work well. I have used several of them.

    Don’t forget to get the “T nuts” too unless you already have them.

  • @dddoo7 I have two T nuts I purchased to put the Arca rail on but didn't use them. I got lucky the Ace here had two in their furniture parts selection. Button head screws are a different story I would order them from BT when I get the rails. Two T nuts and screws for five dollars. I think Area 419 has a video putting a rail on. The guy used a wood paddle bit I'm not too sure about that. I guess if that's all you have do it. My luck it would get away from me and tear up the stock:(

  • @bigfoot

    I use a forstner bit after having already drilled the pilot for the screw. seems like you would be better off.

  • @dddoo7 I have a complete set of Forstner's and a couple of Freud carbide tipped ones. They need to be run in a drill press or mill with a hand drill it might want to walk around I use them up to 35mm but only in a press. Either way I will be finding out soon.