Screws into Carbon Fiber Stock

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Jun 15, 2016
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OK, here's the situation. I have a big hunt coming up in 3 weeks so Im a bit flustered. This rifle is light, I have a great load worked up for it, and have proven it out to 600 yards with confirmed DOPE, etc. Ive put a good bit of time into getting to this point and was feeling very good about it.

I went to install the Spartan Bipod base on my rifle stock using the sling swivel stud threads, and as I tried to tighten it, it started spinning with no resistance and wouldn't tighten. I tried to reinstall the swivel stud and yep, it spins too. Clearly the T-nut is spinning.

So I take the stock off, and again try to tighten the screw from below and I can see the T-nut spinning. It was basically secured at the factory using a glob of epoxy. I use a screwdriver and remove the epoxy and T-nut. Upon inspection the inside of the T-nut is also corroded, and the teeth that are supposed ot bite and hold it in place are bent and not reusable. I go the hardware store and looked at all their metric, standard, etc. T-nuts, and nothing they had was long enough or the correct size or threads to fit my spartan screw or a sling swivel stud.

So I say to hell with it, I'll just use the shooting V on my tripod or shoot off a pack, so I go back home, go to reinstall my stock and action, which requires 65# torque. As Im doing the final tightening, one of the action screws strips! A hex head. I tried using a rubber band, a latex glove around the bit to give some bite, but niether worked. So now I don't even know if the action screws are tightened properly. Going from bad to worse.

The action screw that stripped was the long one going through the trigger guard. I put a tab of blue loc tite on top and let it settle around the end of the screw body.

Now I want to go to the range just to make sure the action screws will hold under fire, and that accuracy has not suffered, but I have no bipod, so not confident that whatever I see at the range will truly reflect the rifles consistency vs my imperfection. So, Im thinking, get a 2-3 inch piece of pic rail and install on forearm, simply using wood screws from the outside of the pic rail and into the stock....no t-nuts from the other side. Will the screws bite into the carbon and hold, or will the carbon splinter, etc.?

(know this is not a long term solution, but right now trying to decide if I can either get this fixed or if I should take another rifle without these issues that weighs 2 more pounds and is 400 fps slower. I don't have a drill press and vise)
 
Is this a Tikka? What stock?

I wouldn’t thread into the stock directly. The filler material in a carbon shell stock is not good for threading.

Doesn’t the spartan mount come with a locking nut?
 
Just use a nyloc nut.

Did the foam out if u need.

Can’t fit a wrench in but I used a large flat blade and crammed it in there to to hold nut while tightening.

If u want to drill the t nut area if called a forstner bit, You can get them on amazon
 
Use a hammer and tap a torx bit into the head of the action screw to remove it, or, drill out the head with a bit a touch larger than the screw body size. When the drill breaks thru the head, it'll pop off and you can use pliers to remove the screw body. This is assuming you have addl action screws.
 
Just use a nyloc nut.

Did the foam out if u need.

Can’t fit a wrench in but I used a large flat blade and crammed it in there to to hold nut while tightening.

If u want to drill the t nut area if called a forstner bit, You can get them on amazon
This is a good idea. A socket wrench with an extension will nicely tighten the nyloc nut. A fender washer will give more support. Some epoxy in the bottom of the hole before you drop the washer in will help build a solid flat base for the washer and nut to tighten against.
 
Great idea! There is a deep square channel they had cut, so plenty of clearance. Now I can take the spartan base to the hardware store and get a screw that fits through and a washer and lock nut.
View attachment 940145
Looks like you got the action out. Nice work. If this is an old picture, and the screw is still stuck, another tactic is to use a Dremel to cut a slot in the screw head and use a large flathead screwdriver to extract it.
 
Thanks for the replies. I’m all set now I think. Got the Spartan bipod base secured. Got a new action screw coming tomorrow so should be able to get torqued up and to the range by Friday afternoon

IMG_8426.jpegIMG_8428.jpeg
 
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