Bipod broke my stock!!! Ever seen this?

[86alaskan]

I have a feeling there may have been some bipod loading involved as well. So, you load it hard anticipating sharp recoil, which flexes the stock probably to the limit one way. then pull the trigger and rapidly flex the stock back the other way, while also introducing a pressure point at the end of the added on rail. lather rinse repeat until failure. seems like a perfect storm that broke that stock.

 

[Woodstuff]

You can see this is a ultra lite foam filled stock . It looks like to me this is not a factory lug at point of break as it is one of the type inserts that is used on wood furniture. It works by the four spurs digging in the wood and completely relied on grain structure of wood to support any stress . Stocks ment for bipod attachment have both swivel lugs factory inlaid and most composit stocks have a aluminum rail molded in the stock for support under recoil . Thus the warning!

 

[aushunter1]

It looks like to me this is not a factory lug at point of break as it is one of the type inserts that is used on wood furniture. It works by the four spurs digging in the wood and completely relied on grain structure of wood to support any stress .

If you read, this is what the OP installed himself

 

[naja302]

Actually I installed the one further forward. The brake is at the factory installed one....not that it matters

 

[JAYgs8163]

Actually I installed the one further forward. The brake is at the factory installed one....not that it matters

I think the additional stud, along with the rail and extra torque, is where the issue arises from. Then add the recoil and you have the end result. I think if you had used a Harris bipod on the original swivel stud you'd not be having this issue. Adding that rail put all the pressure behind the factory installed stud. That bipod you have is pretty hefty looking also as I look at the picture and compare it to the stock portion still on the bipod. Anyways, sorry it happened and I hope you come up with a good solution. Is Cooper now owned by Wilson Arms and Barrels back in Brantford, CT? I once had a Wilson Barrel I had terrible luck with.

 

[Warbird2006]

Don't know what you paid for that stock, but it was to much. It is just a foam filled shell and was weak by design, light weight normally means weak. Not being critical, but that's a shame to build something like that and charge two prices. Some of the most expensive composite stocks I have worked on are built cheep to save cost and make more money.

I would get a refund and buy another brand Because this could have happened on a once of a lifetime hunt and ruined it for you. The last one that I had to install an adjustable but plate looked like the but stock was stuffed with Ziploc's as a filler, and there were no abutments for the screws so we had to build some before the but stock could be installed and the original recoil was just glued to the back of the stock.

Most composite stocks are way over priced and have many other issues, so much so that I have replaced all of mine with wood or laminates and along with the added strength, accuracy has improved on every one of them to some degree.

Sorry for being so negative, but I have seen this before and just don,t want the problems that come with them to shave a little weight.

Just my experiences with composite stocks as a builder.

J E CUSTOM

OK, just pause right there. This is a specialty rifle, Cooper. Very precise, special purpose, ultra-lightweight carrying rifle. Probably for hunting sheep. You can walk and hike with that rifle for hours and when you need to take a prone shot, you put it on your backpack and bang. It's not a tactical rifle, you don't put a tactical rail on it and mount a heavy tactical bipod. Sometimes a little bit common sense does not hurt (and taking a peek at the instruction). I shoot silhouettes and have 2 specialty rifles with light stock. The lightweight stocks are just foam and paint. I would not ever put a bipod on it.

 

[Blacktailer]

Years ago I stopped in to Brown Precision and they told me that they had never, at that time (mid 80's) warranteed a stock even though if one broke they would do so. They heard of one where a horse rolled on it and one where a safari truck had run over it and neither had broken. I have 2 of their stocks and couldn't imagine this happening to one of them. As others have said, it appears there is basically no reinforcing fibers in that break. Looks like it is nothing but Styrofoam. Wonder what the wrist looks like?

 

[JAYgs8163]

Why would any reliable manufacturer install a bipod receptacle on a stock which is not designed to handle the load?

They didn't, as he stated in the original post he did. Repeat

 

[Warbird2006]

Not really, they made a really lightweight rifle to carry and hunt with, the primary design criteria. The stock was no doubt contracted out to a stock manufacturer to meet a price point and weight specification.

Dude, you buy a Ferrari, don't use it as F-250.

 

[codyadams]

Dude, you buy a Ferrari, don't use it as F-250.

I would consider a back country rock climbing sheep/goat hunting rifle more of an F-250. Don't think I would want to take a fragile rifle on a hunt that may be a days horseback ride/hike from a basecamp that is a days truck drive or float plain fly from civilization, where I may need rock climbing equipment to recover the animal I'm using it to kill.

 

[villagelightsmith]

Yup. That's broke. Couldn't have said it better myself.
A few more ounces of cloth would have brought it out of the "ultralight" class, but would have kept it from breaking. We will always grumble about carrying that extra 6 or 8 ounces, never thinking that it saves us from breaking stuff. I spend big money to save a few ounces, then toss a few granola bars and 2 pints of water into my pack. Spare batteries, just in case. A map. Or a couple of pounds of lard on my paunch. There's no shortage of stuff we are happy to toss into our packs.
Great discussion here!

 

[Philward]

Dude, you buy a Ferrari, don't use it as F-250.

Precisely my point, why mount a bipod on a lightweight carry gun? Drop a wood stocked gun off a 20 foot cliff and it will probably break the stock, and maybe some other stuff. Same with synthetic, carbon, kevlar, fiberglass, whatever...If it's a shell material such as this once the shell has been nicked or compromised in some way from impact it's structural integrity is gone. Carbon MTBs and even aluminum MTBs are pretty rigid and can take a lot of force but hit a tube on the side and dent it(alu) or crack it(carbon) and it could fold up and cause all kinds of issues. Carbon arrows the same, get a split in one and shoot it and it may blow up in your face.

 

[pmh-usa]

My original post owes Naja302 an apology: I should have read the entire dialog - I did not know that the manufacturer failed to warn about the use of bipods. I think that if he had not modified the stock, and it had broken, the manufacturer would probably have made it right.

As to the repair, if that was my stock, I would reattach the broken forend and let the method of the repair incorporate an appropriate foundation strong enough to support the use of the bipod. I won't go in to details here because there are alternate ways to accomplish the repair and everyone has their opinion regarding "how". I will say that the challenge is to do it with the least amount of weight gain as possible.

Not meaning to hijack this post and take off on a tangent, but another lesson-learned here is something that Muddyboots said, "I've sheared off bipod studs just from recoil with my 300WM when shooting off a concrete bench."

I've never heard of that happening before but when I visualize it, I wonder why I had not heard of that before. The similar but more common issue I have seen over and over, is that of sling-swivel studs digging holes in rests especially "bags" and other soft rests during repeated shooting. When I do a stock, I use Uncle Mike (or equivalent) studs which have a 10-32 thread; when I return the customer's stock, I always include 10-32 button-head 'filler' screws for the customer to insert in-place of the sling-swivel stud when bench shooting. When the stud is removed, the button-head protects the rim of the stock hole from chipping and keeps crap from getting in stud-bushing hole. The button-head generally can be screwed in almost "flush" or at least it doesn't protrude beyond the stock surface enough to cause issues with the rest; however, just in case, I also include short 10-32 headless set-screws that can be screwed in at or below the surface level. Sometimes when the customer wants stud-bushings for both bipod and sling-swivels, these can be used to fill the unused bushing hole. I have also run into 10-24 sling-swivel studs on both OEM and aftermarket stocks on occasion 90% of what I've seen is 10-32. If you can't find these in a good hardware store, you can find them on Ebay.

If you do have 10-24 studs and would like to convert to the more common 10-32, it's a fairly simple fix and doesn't really involve 'invasive surgery'. PM me and I'll tell you how. Hope this helps.

 

[Bob2650]

Everyone probably has their own idea about the ideal Colorado high country hunting rifle. The Cooper rifle in question probably matches a good number of hunter's opinion of the "ideal" hunting rifle. Mine is a 7-08 16" barrel. One of the thinner versions of sporter barrel and a Bell & Carlson ultralight stock. Peep sight! Yes, iron sights. I used to shoot 600 yards with iron (NRA Highpower) quite often. It is a lot lighter than the Cooper. Recoils about like the typical 30-06. Sorry, it is on loan to a family member who lives in Colorado so I can't weigh it now. Have about $500 total invested in it. Last time I shot it I got slightly under one inch groups at 100 yards. Plenty accurate for a hunting rifle but obviously it is not enough for elk at 600 yards.