Atlas Stock Rails
Last week I ordered three rail sections to mount on the stocks of some of my rifles. Two had curved bottoms for rounded stocks and one flat one that was a 4 inch model. I think the other two were 3.35 inches. First two stocks were easy the Boyd's laminate stock has a recess in the bottom of it and all that was necessary to get the T nuts in were enlarge the sling swivel stud holes to 1/4" and insert the nuts into them and tap them slightly to get the teeth to penetrate the laminate and then tighten the mounting screws and they sank into the wood. Plenty of room in the recess so I didn't have to countersink the T nuts. And this particular stock had two sling swivels in the fore end. Easy breezy. The second stock was a CZ Kevlar type that has an aluminum skeleton throughout the stock that already had one hole for the sling stud tapped in the fore end. Unfortunately it was a 10-24 thread and the button head screws are 10-32 so I just tapped it with a 10-32 tap and called it good. A little Blue Locktite and forget it. The second hole required placing the stock in the drill press and drilling and tapping the back hole. I guess you can pull this off with a hand drill but if you got a press and a vice might as well use it. I used a curved rail for the Boyd's stock and the flat one for the CZ. I took a double cut file and flattened the fore end on the CZ it had a very slight radius but the file took it out with just a few swipes. One more to go I just haven't decided which stock.
Tapping the CZ stock.
dddoo7 last edited by dddoo7
These are worth the time to install. I have installed several of them and they work well. Good run-through and description.
BTW, do you run the tap in the drill press or did it just happen to still be in the drill press?
@dddoo7 Haha, no I didn't run it in the drill press. I would have to have super powers to shut it off fast enough. It's tempting but way too fast a spindle speed. The correct way in mill is to stay centered over the hole and put a center in the mill spindle and use a tap wrench with a center hole in the handle to align the tap to the drilled hole. I would switch the mill to neutral and come down with the quill until the tip of the center was in the tap handle then put a little downward pressure on the tap and start the tap. Get a couple of threads going and back up to break the chip then go a couple turns more and you are started straight with the hole. I tapped hundreds of holes this way until we got tap heads for the mills. In my old drill press I drill the hole then without moving anything I put the tap in the chuck and turn it by hand until the tap gets started then loosen the chuck and use the tap handle. Tapping a hole straight by hand can ruin your day and the piece you are working on but I bet you knew that. We used lots of spiral taps and did bottom hole tapping so they had to really had to line up in the hole but with a mill and a DRO it's no problem until you get down to tiny taps then it gets challenging doing it manually. Later the owner of the shop started using tap mills in the CNC machines and for through holes used gun taps that push the chips out the bottom of the holes. Another tip for tapping a hole is spot drilling before you drill the clearance hole. Spot drilling is always a good thing to do so the bit doesn't walk around but drill the spot deep enough so the diameter of the spot is a few thousands larger than the hole so the tap has relief to start easily and the first chip is formed easier and that helps the tap go straight. Both of these stocks had the sling stud rail adapters and with the bipod installed had movement. These are solid :)