Sako TRG - firing pin

[RTG22]

Hello shooters,

I’m the owner of a Sako TRG-22 in 308.

Lately I have some firing problems, one in every … round does not go off while the primer depth is the same and the case has powder… if I look at the dent in the primer I expect it hits not deep enough… does anybody know what the firing pin protrusion must be measured from the bolt face?

Thx!

The weird thing is that it is one in 50 rounds, but I’m sure the anvil touches the bottom of the primer pocket… I have about 0.008” crush
I shoot lapua cases and CCI primers but I have the same problem with Federal primers

Kind regards,

 

[Redmist]

If you haven’t already done this, I would strip down the bolt and fire control assembly and give thorough clean and re test

If I recall correctly (and I’ve worked on several) the firing pin and sear is a factory assembled part so any shortening of the protrusion may only be resolved with a replacement pin assembly

The tip may become damaged if hot loads have been used (pierced primers) but the bolt head around the firing pin hole would also show signs of wear if that were the case (in extreme cases)

If you get no better ignition after cleaning I’d consider replacing the firing pin and spring (they come from Sako in the same parts bag )

 

[918v]

How do you size your brass? Cuz if you size it too much and mess with the primer pocket then you’ll run into these problems. TRG fp protrusion isn’t an issue.

 

[RTG22]

Thanks! I don’t shoot hot loads and never have been.

I size full length (ok, bump the shoulders back 2th). But I use lapua brass and do not touch the primer pockets other than decapping, wet tumbling and if still some residue is present, scrape it out with a lee tool.

One thing I did change is my primer seater… I changed from a rcbs to a 21st century primer seater. Im sure the anvils are touching the primer pockets. Could it be I crush them to hard? I deprimed the shots that didn’t go off and measured that the anvils where touching the pockets. Also I can’t see any deformation on the primer cup…

 

[918v]

Yes if you’re smooshing them in too hard you may be disintegrating the priming compound and that’s why they aren’t going off.

With the 21st Century tool you should feel the primer bottom out, then check to see the primer is flush or below with the case head. No need to push them in deeper after that.