Tikka slam fire PSA

[wind gypsy]

Reviving this to not further clutter the Rokstok thread..

@mxgsfmdpx mentioned shimming the aftermarket bottom metal to avoid slam fires, is there a tutorial on this somewhere? I have some High Desert bottom metal on the way for the rokstok and have MT bottom metal on another tikka, want to make sure I'm safe with these rifles..

 

[mxgsfmdpx]

Part of the equation on my rifle is also the softer aftermarket trigger spring installed, combined with multiple aftermarket parts and tolerance stacking... I am guessing that with the factory trigger spring, you may not need the shims, HOWEVER, please carefully review the guide provided by High Desert (linked below).

As a note, both of my Stocky's VG2 stocks and now my Rokstock have required the shims when torqued to high values. If you torque to lower values (below around 50" lbs) you will also not likely see the slam fire issue. Mine are all set to 65" lbs with shims and I cannot get them to slam fire anymore, even with an aftermarket softer trigger spring.

Also, as another side note, the following brand stocks (multiple samples of each) never gave me slam fire issues, meaning, blaming the soft trigger spring isn't necessarily "fair" or the "root cause"... McMillan, KRG, Mesa Altitude, AG Composites, Manners, and obviously a dozen or so factory stocks both their faux wood style and plastic.

Here is their explanation as to why shims here...

Why do some Aluminum Bottom Metal/Trigger Guards need a shim?

Why do we include a shim kit with our Aluminum Bottom Metal/Trigger Guard? During our exhaustive testing, we found that factory Tikka stocks are not uniform regarding the bottom metal/trigger guard well. In some instances, when an aluminum bottom metal/trigger guard is installed on a factory...

highdesertrifleworks.com

Here are instructions...

How to Install our Tikka T3/T3x Bottom Metal

INSTALLATION INSTRUCTIONS FOR TIKKA T3/T3X ALUMINUM TRIGGER GUARD 1. MAKE SURE THAT THE FIREARM IS UNLOADED. IF THE FIREARM IS LOADED, UNLOAD IT. MAKE SURE THAT THERE IS NO AMMUNITION IN EITHER THE MAGAZINE OR CHAMBER. 2. CHECK AGAIN TO MAKE SURE THAT THE FIREARM IS UNLOADED. REMOVE MAGAZINE AND...

highdesertrifleworks.com

 

[mxgsfmdpx]

Can someone please link to the precise Loctite product you would recommend for a screw like this? Going to proactively apply to all my Tikka's.

I’ve used this make/model in various applications for close to 30 years now. Not sure how often the recipe has changed, but the stuff does its job.

 

[ID_Matt]

I'm confused why shims or lack of on the bottom metal would cause a slam fire. Can someone explain?

 

[Fireflyfishing]

The other day I was out in the shop messing around and decided to pick up one of my Tikka's and practice manipulating the bolt rapidly. After a time or two something didn’t feel correct. It was releasing the firing pin on closing. Luckily it was on an empty chamber.

After a close inspection and tear down, I found the problem to be the Allen screw holding the trigger assembly to the action was loose. Upon further examination, it took roughly 1/4 of a turn from tight to allow enough slop in the trigger assembly for the seer to release the firing pin. I also noticed this screw does not have any loctite applied from the factory (checked two other Tikkas).

Going forward every one will be loctited!

Not sure why it was loose, could have shot loose or the smith who shortened the barrel a couple hundred of rounds ago my have not torqued it properly. Ultimately it is my gun and my fault for not checking everything. I do know that the sinking feeling in my stomach was terrible, especially knowing that my wife and father just used the gun on hunts. Fortunately nothing bad happened, but from now on trigger housing screws will be checked, torqued, and loctited!

Ryan

Cool. Thanks for the heads up.

I have a .308 CTR and the trigger needs no new spring on my rifle. I like it just the way it is…but something to check when it’s our of the stock from time to time.

 

[Amos Moses]

Thanks for the heads up on this. Just added loctite to both my tikkas and retorqued to 55. They were both snug, but had both barrels cut and threaded recently.

 

[tpicou]

As a note, both of my Stocky's VG2 stocks and now my Rokstock have required the shims when torqued to high values. If you torque to lower values (below around 50" lbs) you will also not likely see the slam fire issue. Mine are all set to 65" lbs with shims and I cannot get them to slam fire anymore, even with an aftermarket softer trigger spring.

Also, as another side note, the following brand stocks (multiple samples of each) never gave me slam fire issues, meaning, blaming the soft trigger spring isn't necessarily "fair" or the "root cause"... McMillan, KRG, Mesa Altitude, AG Composites, Manners, and obviously a dozen or so factory stocks both their faux wood style and plastic.

Do you think the stocky’s are more compressible so the high torque (without shims) leads to it loosening over time and causing the slamfire?

 

[NSI]

Do you think the stocky’s are more compressible so the high torque (without shims) leads to it loosening over time and causing the slamfire?

No. This is all about geometry, particularly around the trigger shoe exit.

-J

 

[GoBirds]

Can someone help me understand why the trigger mounting screw coming lose would cause the firing pin to drop?

 

[Southern Lights]

The Tikka trigger assembly is held in the action by allen screws. The trigger sear engagement with the firing pin is very small. If the trigger assembly is loose, it is entirely possible it could clear the firing pin and make it fire on bolt close if rattled around.

This shouldn't happen if the safety is on as there is a pin that blocks the firing pin when activated. But if the safety is not on, and the trigger assembly has been altered from factory spec/loose, I can see how it could fire on bolt close.

But this is not a problem with the rifle. It's usually because people have been modifying/disassembling/changing bottom metal/etc.

IMPORTANT NOTE: If you remove or tighten the trigger group with the bolt in the receiver it will instantly destroy the trigger sear of the Sako TRG. The Tikka T3 likely would do the same. If you have to detach the trigger for whatever reason, don't put it back in with the bolt in the receiver. Same if you need to tighten it. Remove the bolt first, then tighten the trigger group, then put the bolt back.

The Tikka factory trigger is excellent and I would never alter it. European spec rifles that cannot be imported to the US often have set triggers. You press the trigger shoe forward and it goes to about 1-2 ounce break. So the Europeans can make light triggers. But again I'd just advise please leave the Sako/Tikka triggers alone. They are excellent from the factory and don't need fixing. Adjust according to factory specs and they always work well and are extremely reliable in all weather.

 

[Sandstrom]

One other thing I noted when my trigger assembly screw was around 1/8 turn loose, it would randomly slam fire from bolt manipulation. It would also release the firing pin by slamming or hitting the rifle. It would also release the firing pin if you pushed down on the safety (which would move the whole trigger assembly down enough to release the firing pin). Once I figured out what the problem was, I “experimented” with several different “degrees” of trigger assembly bolt looseness. Anything over roughly 1/8 turn from tight caused a very dangerous situation.

Ryan