Firing upon bolt closing

[Switchbarrel]

History first...

Rifle started as 6BR with SSS Competition trigger...no trigger/firing problems.

Rechambered to 6 Dasher. Denting some primers, not igniting them...no other trigger/firing problems.
Had Kevin Rayhill install a new, stiffer firing pin spring.

Went to try it out today and after 2-3 shots, I closed the bolt and it fired the round (no my finger wasn't on the trigger). I'm able to repeat it pretty often opening and closing the bolt quickly. So, the only change prior to the problem is switching to a stiffer firing pin spring (Wolff 32lb).

Before I go messin' around with adjusting the trigger/sear, or swapping out the firing pin spring again, I thought I'd see if there's anything else I should consider or adjust?

Picture below should take you to a video.

http://i37.photobucket.com/albums/e62/Switchbarrel/th_IMG_0035.jpg (http://s37.photobucket.com/albums/e62/Switchbarrel/?action=view&current=IMG_0035.mp4)

[82boy]

Sounds like you need to go back to the old firing pin spring. To add, there is no advantage in going to a heavier spring, all it will do is give you a heavy bolt lift, and possibly a harmonic problem which will affect accuracy. The factory Savage spring is already to heavy from the get go. I have never had any ingnition problems with any type or brand of primer with a factory and much lighter spring. (Actuly most of my savages have lighter than factory spring, and have never had a problem even with mag primers my 6x47L never has had a problem.) Sounds like you have a firing pin purtursion problem.
You could adjust the sear engaugement on the trigger, and possibly fix the problem, but I would get rid of that heavy spring.

[stangfish]

Does it fire or does the primer get ignited on the bolt closing? The former being a trigger adjustment and the latter a FP protrusion?

[tiny68]

My Evolution trigger would slam fire. I had to engage the sear just a little more (1/4 turn) and the problem was solved. 2 oz triggers are touchy little things. Even Jewels have to be re-tuned/re-set occasionally. Luck, Tim

[Switchbarrel]

Does it fire or does the primer get ignited on the bolt closing?


As seen in the video above, I can work the bolt quickly and the firing pin will drop without pulling the trigger, igniting the loaded round. If I close the bolt slowly,
it does not drop the firing pin...at least not yet in my limited testing.

I'm hoping I just need a little more sear engagement with the stiffer firing pin spring. I believe I'll try adjusting that first,
hoping it will correct the unwanted firing condition. I want to keep the stiffer spring in if possible to see if it fixes the
failure to ignite issue that was occuring previously. Certainly didn't fail to fire yesterday. Firing pin protrusion does not seem
to be a problem...near as I can measure it.

Thank you all for the input.
-Rick

[stangfish]

My Evolution trigger would slam fire. I had to engage the sear just a little more (1/4 turn) and the problem was solved. 2 oz triggers are touchy little things. Even Jewels have to be re-tuned/re-set occasionally. Luck, Tim


Yep, Your on the right track now!

[LHitchcox]

Definitely a lack of sear engagement.

[SMK Shoe]

Rechambered to 6 Dasher. Denting some primers, not igniting them...no other trigger/firing problems.



Are you shooting reloads? and if so, did you size them or someone else. Sounds like either a headspace problem or the shoulders were set back a little to far. Heavier spring on the firing pin is NOT going to make it reach any farther. Savage firing pin springs are 3 to 4 time's MORE than needed for ignition. Really sounds like the case is not tight to the bolt head and is being pushed by the firing pin, which is using up most of the striking energy. Try the factory spring and load a couple of rounds with the bullets jammed in the lands. that will keep the round up tight to the bolt head and see if any FTF. As for the firing when you close the bolt, Sounds like the trigger is adjusted to low. Sorry to hear about the problems, Firing when you don't want and not firing when you do.

[stangfish]

Rechambered to 6 Dasher. Denting some primers, not igniting them...no other trigger/firing problems.



Are you shooting reloads? and if so, did you size them or someone else. Sounds like either a headspace problem or the shoulders were set back a little to far. Heavier spring on the firing pin is NOT going to make it reach any farther. Savage firing pin springs are 3 to 4 time's MORE than needed for ignition. Really sounds like the case is not tight to the bolt head and is being pushed by the firing pin, which is using up most of the striking energy. Try the factory spring and load a couple of rounds with the bullets jammed in the lands. that will keep the round up tight to the bolt head and see if any FTF. As for the firing when you close the bolt, Sounds like the trigger is adjusted to low. Sorry to hear about the problems, Firing when you don't want and not firing when you do.



For the sake of discussion I have heard a lot of people talk about how overpowered the spring is on a savage. This may be due to the low mass of the savage firing pin. I discovered this when I noticed that most of the aftermarket springs were heavier. Good read if you are working on your own bolt. http://www.switchbarrel.com/Spring.htm

[geargrinder]

Definitely a lack of sear engagement.


+1

Looks like lack of sear to me also.

[Ring31]

Definitely a lack of sear engagement.


this...

[GUNFANATIC]

Definitely a lack of sear engagement.


+1

Looks like lack of sear to me also.


Yep. Seen it many times. That's the reason I quit adjusting other people's triggers lower that 3lbs. I get mine to about 2lbs. Takes alot of filing and stoning to make it safe though.

[sharpshooter]

Increasing the mainspring pressure puts more load on the trigger. Increasing the load on the trigger will wear the fine edge of engagement, and this is probably what happened. There is no rifle I know of that needs a 32lb main spring. All it does is increase the cocking effort and makes the trigger pull harder, while affecting the harmonics.
If you were having ignition issues before, it was most likely caused by short firing pin fall.