Safe to Shoot?

[nucular]

Rifle is a Tikka T3X UPR chambered in 6.5CM. I just noticed a crack in the stock behind the bolt and have sent in a warranty claim. I have only put a couple hundred rounds through this rifle. Mix of factory 140/147 ELD-Ms and I also did some ladder testing of 147 ELMs over H4350 the other weekend. I don't know at what point the crack surfaced but I don't believe this is an overpressure issue. I didn't see any flattened primers, bolt hang, or anything like that. Curious on your thoughts of if this could be an overpressure and whether or not it is safe to shoot in the meantime. I was planning on going to the CIHPRS new shooter class coming up but if it's a safety issue, I will either need to pass or look for a replacement stock.

 

[mike4]

If you want someone to tell you, go ahead and keep shooting that rifle, that is not me. If you want someone to tell you, stop shooting that rifle until the stock is properly replaced, that is me.

The action remains as safe as it was before it cracked. I have no knowledge of how safe it was/is, but if it was not out of spec from the factory, bolt lugs were not stressed by overpressure loads, etc. then your bolt is locking closed into the receiver as always.

What is not safe is having the stock randomly split or shatter down that side when you fire a round. When a centerfire round with that much power is fired it's like hitting the stock with a hammer. Think about what the recoil would feel like if you had a steel buttplate AND a solid metal stock. That's what's hitting the stock every round, and it depends on proper distribution of that force across all points of contact between the action and the stock.

It's likely the stock had a manufacturing flaw or improper fit with the receiver that concentrated forces in one area. Now that it's cracked the stresses are not spread throughout the stock material, which already could not hold up to it to begin with. Stresses are all concentrated at the edge of the crack increasing the probably of crack growth and sudden complete failure.

If that was the factory stock that came on the rifle and it's under warranty and you weren't brewing up rounds above SAAMI pressures, I'd say Tikka owes you a new stock. They might require you send the whole rifle in to fit it.

Again, I do not think it is safe to shoot because of the potential for the stock to collapse. At a minimum you might learn what your scope would do to your eye socket if you don't have the stock controlling recoil between there and your shoulder. I'm also unsure you are going to have any kind of decent long range accuracy with the off center flex as recoil forces are hitting that stock well before the bullet leaves the barrel.

My advice, engage warranty or buy and properly fit a new stock. Pull out or borrow another rifle for the class. (And +1 one for asking the question. The uncertainty behind the question is your own wisdom and common sense asserting itself.)

 

[russc2542]

Mike covered it well. It might be fine for hundreds of rounds, it might throw off your accuracy, it might fail completely allowing the scoped action to go wherever it likes.

 

[nucular]

Yeah, after my disappointment faded, I came to the same conclusion. I called Beretta and the warranty will require the entire rifle to go in and won't happen for 5+ weeks. I don't have a backup rifle that will work for the class so I just decided to buy another stock. Kind of a bummer because I got the more expensive UPR due to it's PRS-like stock. I'll probably just warranty it after the class and sell the stock assuming they replace it.

 

[BigMoose]

I have never seen a synthetic stock split like that, somewhat like a wooden one would.

But yep, it split from the screw hole..

I am going with some sort of defective stock.. and because it’s synthetic, who knows how it’s going to act. You can trust wood to split down the grain, there is no grain on that stock and who knows what it’s gonna do.

6.5 isn’t a huge recoil producer from what I understand. I am half curious now to see if there is a unintended void in that stock. But that would involve destructively prying open the stock.

 

[nucular]

I have never seen a synthetic stock split like that, somewhat like a wooden one would.

But yep, it split from the screw hole..

I am going with some sort of defective stock.. and because it’s synthetic, who knows how it’s going to act. You can trust wood to split down the grain, there is no grain on that stock and who knows what it’s gonna do.

6.5 isn’t a huge recoil producer from what I understand. I am half curious now to see if there is a unintended void in that stock. But that would involve destructively prying open the stock.

I'm curious too. I did notice that the triggerguard piece doesn't really sit flush in the stock. It rocks back and forth between the 2 action screws. Not sure if that factored into it.

 

[BigMoose]

I'm curious too. I did notice that the triggerguard piece doesn't really sit flush in the stock. It rocks back and forth between the 2 action screws. Not sure if that factored into it.

Ohh hell, something is way wrong with that stock then. Particularly if it doesn’t do that with the new stock. It almost sounds like the dang action is not properly bedded into the stock. Well bedded, I am old wood guy LOL. anyway, there should be enough meat in the stock for the action to properly clamp on. If the stock is too thin, and there is nothing it’s able to clamp onto, then those screws are just being rammed back into the stock, and thus the cracking. The floor plate/trigger guard should not be able to move. That screams improperly bedded stock. Or fitted stock I guess, since yours is synthetic,