Thread: Bedding flush cups into a carbon fiber stock

Recently purchased a new boom stick for my collection and needed to fit a new flush cup adapter for my javelin bipod as their universal adapter sux arse.
Normally I would pay for such a service but with @stug retired from stock manufacturing and modding I decided to have a crack at it myself.....with a little guidance from Stu, thanks mate your a legend

Drilled out the hole carefully then opened it up with the dremel as I didn't have a drill bit big enough to match the diameter of the flush cup.
Once the hole was the right diameter I opened up the cavity a little with the sanding drum on the dremel to make room for the epoxy to bed it in.
Made a dam out of blutack to stop the epoxy spilling out into the swivel stud cavity, also sealed around the bottomed of the flush cup with lilac to stop it dripping whilst I poured 2 pot epoxy inform the top with the stock clamped into the gun vice.
Came up mint.

Then I tried to fit the bipod the other way to lock it instead of free panning.......



#fail

Oh well at this stage I had a few options,

I could move the swivel stud forward (easiest).

I could opt to only use the bipod in free panning (stupid as I often use it locked as I prefer it).

Or I could use my new found skill to go stupid drilling lots more holes in my stock mounting flush cup sling adapters in the side so the rifle sits flat on my back when slung (what could possibly go wrong ? I mean a replacement carbon stock is cheap enough if I screw it up ).

Anyway ordered some uncle Mike's QD flush cups and set to work with the dremel, bloody nerve wracking drilling holes in c/f especially not really being known for my craftsmen ship

I put a square of masking tap where the holes were to go then traced the base of the flush cup onto the tape.

I then marked the center and then measured the drill bit against the flush cup and marked it with electrical tape so I didn't drill any deeper than needed.
Started with a small drill then progressed to the biggest one I had again marking the dtill bit with electrical tape so I wouldn't drill too deep.

Again like the bipod adapter I opened the hole up till the flush cup fitted in snug.

Then opened up the hole under the skin of the stock to allow room for the epoxy bedding.

I then plugged the hole in the bottom of the flush cup with bluetec, and poured the epoxy in the cavity in the stock then with the stud attachment plugged so I could use it as a handle, I pushed the stud in until it was just proud of the stock and as I did that I wiped the excess epoxy off the stock then removed the stud attachment and made any tweaks to the cup and wiped off any excess epoxy.

Very pleased with the results not bad for a first effort and relatively easy, if I can do it anyone can. Just take your time and easy does it with the dremel.

Please note the last pic is before I did the rear QD stud

Originally Posted by berg243

never seen these qd for slings might have to look into getting some. nice job.

You will need to either buy a QD sling or fit the QD sling attachment to your current sling but that's easy enough

https://www.gunworks.co.nz/shop/item...-action-rifles

Originally Posted by dannyb

Recently purchased a new boom stick for my collection and needed to fit a new flush cup adapter for my javelin bipod as their universal adapter sux arse.
Normally I would pay for such a service but with @stug retired from stock manufacturing and modding I decided to have a crack at it myself.....with a little guidance from Stu, thanks mate your a legend

Drilled out the hole carefully then opened it up with the dremel as I didn't have a drill bit big enough to match the diameter of the flush cup.
Once the hole was the right diameter I opened up the cavity a little with the sanding drum on the dremel to make room for the epoxy to bed it in.
Made a dam out of blutack to stop the epoxy spilling out into the swivel stud cavity, also sealed around the bottomed of the flush cup with lilac to stop it dripping whilst I poured 2 pot epoxy inform the top with the stock clamped into the gun vice.
Came up mint.

Attachment 144128

Attachment 144129

Nice. What epoxy did you use?


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Nice work Danny.

I've recently embedded 3 of those adapters into carbon stocks and like you I had a faceslap moment when I thought I'd put one adapter into the stock incorrectly. Turns out I didn't.. but for a few minutes I was kicking myself.

For my stocks I drilled the 19mm hole with a fly-cutter then used a modelling knife to cut a 5mm wide channel fore and aft in the foam core as well as laterally to spread the load of the recoil away from the very thin shell of the outer carbon layer. I used high-strength two part epoxy resin available from Mitre 10 to bond the adapters in place, in my case just one of those two-tube retail kits made by Locktite. After the adapter was correctly located and things were cleaned up a bit I fitted the bipod to make sure everything was square then used masking tape to ensure it remained in place. I left everything overnight to set.

All rifles have been field tested and work fine. To date nothing has moved but I did talk with one person a couple of years ago who stated they had found it difficult to get the adapter to stay secure due to the internal foam core being quite soft on some stocks. It was this concern which put me off doing it in the first place, but I figured the manufacturer of the Javelin has a couple mounted in his Sako Carbonlight (if you look closely at their videos online) and the Duley's had glued one into their 7mm RemMag without drama... so how hard could it be, right???

I like your sling QD cups idea. I miss that setup after handing in my AR-15 last year. It just seemed to work really well for me. I see the Sako S20 has them fitted... I wish my stocks did. Where did you buy those inserts from @dannyb?

Originally Posted by janleroux

Nice. What epoxy did you use?


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Just high strength 2 part epoxy that comes in the syringe that you can buy from mitre10.

Originally Posted by planenutz

I like your sling QD cups idea. I miss that setup after handing in my AR-15 last year. It just seemed to work really well for me. I see the Sako S20 has them fitted... I wish my stocks did. Where did you buy those inserts from @dannyb?

There is a link in one of the above earlier replies I got them from gunworks "uncle Mike's qd push button swivel studs"
I'm pretty sure most hunting shops would be able to supply them if your not keen to do the paperwork thing.

Got my sling back from the saddle maker (aka Mum ) she stitched the new swivel studs into my sling.
Very happy with the results, it's much more comfortable to carry.

I got mine from Brownells.

Only thing I have found with mine is that with moving thru bush and crap if you don't hold the slack in the sling the swivel can on occassion do a full turn. Next time you shoulder the rifle there is an annoying twist in the sling.

Mine were fitted to a wooden stock so no issues with gluing.

looking at first photo with sling stud in the way......the thought came to mind you COULDVE used said dremel and taken some of the top metal off sling stud and bipod couldve gone past then...much prefer your current option....think it was the M1 Carbine and some mausers that had slings attaced in similar manner,the rear was attached to a pin set in face of stock,sure is nice carrying with no bits jabbing in the back.

Originally Posted by Micky Duck

looking at first photo with sling stud in the way......the thought came to mind you COULDVE used said dremel and taken some of the top metal off sling stud and bipod couldve gone past then...much prefer your current option....think it was the M1 Carbine and some mausers that had slings attaced in similar manner,the rear was attached to a pin set in face of stock,sure is nice carrying with no bits jabbing in the back.

Not a chance could not have taken enough material off to allow it to fit, definitely happy with the current set up it's much nicer to carry this way

yeah it sure looks comfy to carry that way.
great work.....just spotted a familiar couple of faces in the Rod n Rifle mag.......must read them soon LOL.

can that same Mitre10 epoxy be used to fix a couple of cosmetic chips and screw holes in a kimber stock?

sounds like you are talking about the syringe type with two tubes that mix as it comes out? I think arildite make it?

Originally Posted by Bill999

can that same Mitre10 epoxy be used to fix a couple of cosmetic chips and screw holes in a kimber stock?

sounds like you are talking about the syringe type with two tubes that mix as it comes out? I think arildite make it?

I'm sure it would be up to the task