Jewell Trigger Damage From Blown Primers

[Joe]

I've been following along with the other threads discussing Jewell triggers and have read that a blown primer can cause damage to a Jewell trigger by thefiring pin blowing back or rebounding.
Can anyone describe this damage?
Is it visible from the outside of the trigger without disassembling the trigger unit?
Is it repairable or does it render the trigger useless?
Do you have pictures of this damage?
Thanks a bunch
Joe Cowan

 

[Hal D.]

I've been following along with the other threads discussing Jewell triggers and have read that a blown primer can cause damage to a Jewell trigger by thefiring pin blowing back or rebounding.
Can anyone describe this damage?
Is it visible from the outside of the trigger without disassembling the trigger unit?
Is it repairable or does it render the trigger useless?
Do you have pictures of this damage?
Thanks a bunch
Joe Coan

Joe, I have seen the one or more levers in a couple of Jewell's in pieces due to blanked primers. I doubt that Jewell's are the only triggers that can suffer this fate if a primer is blown. A blown primer can also fill the trigger with crud as the bolt is where the gases will travel. It's a good idea to have an extra trigger with you when you go to a match...just in case.

 

[Mike Bryant]

What causes this is that when the primer blanks, the cocking piece is blown to the rear. The top bar in the trigger raises back up by internal spring tension of the trigger mechanism while the cocking piece is at the rear of it's travel. Then the cocking piece is driven forward by the spring tension from the firing pin spring hitting the raised part of the trigger top bar. The cocking piece acts like a minature hammer hitting the top of the trigger. Do it enough and something can break on the trigger. I've only seen this happen twice, but it happened on the same rifle within two days apart. One time, the top bar broke and another time an internal lever broke. Both times the trigger wasn't operational again until it was fixed. Jewell considers this mis-use of their triggers and isn't covered by warranty. They will fix it for a fee, however. In Stuart Otteson's book, Benchrest Triggers and Actions, this was mentioned on the Kenyon trigger. Kenyon solved it by drawing the top bar back a little to keep it from being as brittle as it was at full hardness.

 

[Bob Kingsbury]

Center link

Joe, the adjustments instructions supplied with a jewell trigger
show the internals pretty well. Although the top bar
receives the first rearward impulse from the cocking
piece, it is a rather stout part compared to the "L"
shaped center lever. That center lever is in its strongest
form in the cocked position, but becomes a victim of
its own enertia once it moves in the smallest way. It
is the thinest part , and must move rapidly out of its
position for the trigger to work. Once this piece is
broken, the trigger cannot reset. Spring damage is
also common.

 

[Rick B]

If you have been blanking primers...

don't forget to take the firing pin assembly out of the bolt body. The tip of the firing pin may be damaged and this does not do the spring any good either. The inside of the bolt body needs to be cleaned and inspected as some of the little disks may have built up in there and can cause problems. I have seen some that had enough disks in there that there was no longer enough firing pin protrusion to set the primer off.

I hope you are wearing good shooting glasses, too.