How can I fix a cracked stock in Sako M995

[David_S]

My son and I recently purchased a Sako M995 in 6.5x55SE with a view to using it on longer shots on chamois (250-350 yards). We were very pleased when sighting it in to get 0.5 to 0.75 MOA at 100yds with our first reloads. So took it away for a week's flycamping/hunting above the bushline.

Conditions were foggy and damp most of the time but not particularly bad. A couple of light frosts and a bit of snow as we walked out. So we were dismayed to find the synthetic stock had cracked just behind the trigger guard as indicated by the chalk in the picture below. The rifle had not been dropped or abused at all (we were taking extra care on its first outing) and we only fired about four shots in all. I can't think that the cold had anything to do with it - this is after all a Finnish rifle!

http://i206.photobucket.com/albums/bb183/ightham/Guns/DSCF4558Small.jpg

So what do you think caused the crack and how should we go about fixing it? I have only had walnut stocks before (on my two Winchester Model 70s) and both these rifles have stood up to a lot of abuse in the mountains without serious harm apart from scratching. Is this a common synthetic problem?

The crack does not extend around the stock but visibly opens if you flex the rifle.

Incidentally my local gunshop thought it might be a McMillan stock but I can't think of any reason why the original Sako stock should have been replaced. Is there any way of distinguishing a McMillan from a Sako stock?

[Scorch]

Breaks like you are describing typically occur when someone or something sits on or leans against the stock. Pack horses ae notorious for leaning or falling on rifles. The wrist is the weakest point on a stock, and it typically separates right at the point yours did.

I am not exactly sure what kind of stock you have on your rifle, layed up cloth like a Brown Precision stock or molded foam like the HS Precision and McMillan stocks (I assume the latter due to the type of break). For a crack like you describe in a molded foam stock, you would need to completely separate the pieces and insert a rod of some material (I used to use rods cast out of AcraGlas for repairs like yours), then fill in any voids with AcraGlas, clamp the pieces together firmly (I use surgical tubing) and let it cure, then clean it up and refinish it. For a layed-up cloth and resin stock, you would do the same, but you also need to repair the cloth in the area of the break.

[David_S]

Thanks for that advice Scorch.

I am pretty sure it is the original Sako stock as it looks identical to photos I have seen of other M995s. According to Sako's M995 manual

The polyurethane stock is embedded with a synthetic skeleton to obtain maximum stock rigidity. The exterior is finished with a dura-coat paint to provide a durable long-lasting protective coating which requires no maintenance.

Does the "synthetic skeleton" alter your advice?

As for the cause, we didn't have pack horses unfortunately as we toiled up to over 6000' with a week's supplies on our backs but your typical scenarios suggest a possible explanation for this break. We sleep under a fly on foam cell mats lying directly on the hard ground and normally place our rifles beside us on the ground sheet. Helps to stop us rolling off our mats and into one another in the night. However it is not uncommon to roll onto the rifles - no problem with the walnut stocks but from what you say not good for synthetic? Heh! I thought synthetic stocks were stronger than wood?

And by the way my son did pot at a chamois without leaving his sleeping bag.

[krs]

You'll know more about the makeup of the stock when you cut it preparatory to repairing it.

Whatever type it is I like Scorch's plan for rods set into one side and secured with glass, or an epoxy then mated to previously drilled sockets in the other half and also secured. I'd be likely to use delrin material for the rods - it can be bought in 6 ft lengths and various diameters from a place like McMater-Carr or Enco. I'd use at least two rods to keep the halves aligned. Just like dowels in a piece of furniture.

[Wildalaska]

Those stocks are notorious for cracking and Beretta will beat your wallet to death for one :)

You are getting good advice here, I would add that after your affix the two pieces together, wrap the joint with fiberglass tape..

WildthenstartsandingAlaska TM

[David_S]

Those stocks are notorious for cracking and Beretta will beat your wallet to death for one

....and I thought Sako made quality rifles!!!

Delrin rods seem a good idea. Wrapping the joint with fibreglass tape would make a stronger joint and is also a good idea but would probably not look pretty even when painted - still it is a working rifle not an ornament.

Thanks for the suggestions guys. At least I now know it can be repaired.

David

[Scorch]

The polyurethane stock is embedded with a synthetic skeleton to obtain maximum stock rigidityPolyurethane could be a problem. Many of the synthetic materials are virtually impossible to get epoxy gel to adhere to, so once it's broke, it's broke. Try repairing it the way suggested, and if the epoxy won't stick, look for another stock. Bell & Carlson or McMillan stocks are OK, but I prefer a laid-up cloth and resin stock like Brown Precision, MPI, or Lee Six make. A bit more money and work, but once you're done, it's done right.

[dipper]

Find out exactly what the stock is made of---what synthetic material.
I build composite boats as a hobby, the boating industry has all kinds of epoxies and matts and cloth to choose from--but like was stated, they are not all compatible so you need to know what you have.
If there is a boat builders supply in your area, you could check with them when you know exactly what the stock is made from---or you could go here:
http://boatbuildercentral.com/
these guys know their stuff and can supply anything you need---or you can put a McMillan stock on it--one of the best you can get.

Dipper

[David_S]

Thanks guys for the comments. They are all helpful.

Find out exactly what the stock is made of---what synthetic material.

That I think will be the problem. How do I identify the material? Perhaps take it to a local boatbuilder?

Also what is meant by a "synthetic skeleton"? I presume it is a frame made of delrin or other synthetic material which provides the structural strength whilst the polyurethane is used to provide only the shape and contouring. Is that correct?

If I cut the stock in half to insert pins I will cut the skeleton too which is probably doing a better job if intact than pins would. I rather suspect that the skeleton is still intact as the stock feels pretty solid even with the crack - I have to apply a fair bit of pressure to get the crack to open up even a little. So perhaps the crack is more cosmetic than structural and may just need opening up and filling with the appropriate glue and clamping till set with perhaps a subsequent sleeve of fibreglass tape. I have done a fair bit of amateur boat building over the years so I am not unfamiliar with the technique.

Thanks

David

[dipper]

DO NOT CUT THE STOCK IN HALF!! No need to.
Call the company customer service etc. --with alittle work you can find out what the stock is made of--then get the proper epoxy.
My guess is that all that needs to be done is get a dremel tool with a carbide burr and grind/open up the area of the crack--don't get carried away.
Unlike glue, epoxy is a gap filler and actually needs a gap to work properly and reach maximum strength ---if you have done composite boat building, you probably already know this.
You can mix the epoxy with any number of "fillers" but I can't tell you which one is best right now---the repair will be stronger than the original stock if done properly and there certainly will be no need to wrap any kind of tape or matting around it.
Done correctly only you'll know it was repaired--you can even tint the epoxy black if you like ---then repaint---there are all kinds of paints available and you can even texture them--as much as you want.
If you get the proper epoxy, this is no big deal and a fairly easy repair.
Find out what you have and go from there.

Dipper

[David_S]

My guess is that all that needs to be done is get a dremel tool with a carbide burr and grind/open up the area of the crack--don't get carried away.
Unlike glue, epoxy is a gap filler and actually needs a gap to work properly and reach maximum strength

Thanks Dipper. That was the conclusion I was coming to. If it works, great. If it doesn't I can try more drastic measures.

By the way this is the country we hunt with the M995. A couple of chamois at 6,500 ft and 275 yards away in plain view of our camp. They have their winter coats on and are hard to spot unless they move or stand on the skyline which they love doing.

http://i206.photobucket.com/albums/bb183/ightham/Hunting/DSCF4234cropSmall.jpg


David

[dipper]

OK , now I'm jealous!!
Nice.

Dipper

[homefires]

Just a stupid question! Is the stock cracked or is it just the Finnish? Looks like epoxy that has been buckled to me in the photo.

[David_S]

Just a stupid question! Is the stock cracked or is it just the Finnish? Looks like epoxy that has been buckled to me in the photo.

Not a stupid question - the Finnish stock is cracked not the Finnish finish as far as I can ascertain.:p

Though it is hard to be certain as the crack does not open much when the stock is flexed. I think Dipper's dremel treatment will reveal for sure which it is.

David

[homefires]

So the only way to ascertain if the Finlandish Finish is the culprit is to do away with the Finish?:rolleyes: