PDA

View Full Version : Primer hits elongated


Micrometer
June 20, 2005, 09:43 PM
New Taurus PT 140 in 40 S&W. First firing and I noticed the spent primers had elongated hits instead of the nice circular dimples. All 200 rounds fed, fired and ejected great. In a 1911 this usually indicates a weak firing pin return spring. My question is does this in anyway compromise the reliability as a self defense weapon (utterly reliable).

I wrote Taurus and they haven't sent me back a message yet so I thought I would try this forum.

Much Appreciated.

Handy
June 21, 2005, 10:32 AM
I can't imagine that side load is very good for the firing pin. It isn't built to be stressed that way.

Avizpls
June 21, 2005, 10:50 AM
Mine did that too. Seems to have tapered off, or i stopped noticing. Please do let me know what Taurus has to say

Coltdriver
June 21, 2005, 11:21 AM
The elongation or smearing of the firing pin mark on the primer is very common with the .40 round. It is not restricted to your gun. I had the same phenomenon occur with a Kahr MK40. My smith told me it was common.

Nothing to worry about.

Harry Bonar
June 22, 2005, 04:44 PM
Dear Shooter:
I think COLTDRIVER is right; these pistol cartridges that head towards 40,000 copper units of pressure just unlock before that pin gets back in. I don't like it either. Some pins are shaped with a verticle contour to avoid breaking.
Good shooting!
Harry B.

Jack Weigand
July 3, 2005, 12:37 PM
That is firing pin wipe and it is caused by the barrel dropping out of battery before the firing pin has retracted. The real cause here is the ramp on the bottom of the barrel not having enough flat before it unlocks the barrel. I did some consulting for Taurus in the early 90's and they didn't understand the problem then either, LOL! You can use a heavier firing pin spring and also a heavier recoil spring to lessen the problem. Firing pins can break depending on how far they are sticking out when the case is being dragged across them. I hope this was of some help.

Dave Sample
July 3, 2005, 01:58 PM
This seems to be a 40 S&W thing but I have seen it in 38 Supers that were not timed up right, also. I only built a couple of .40's before I gave up on them. I never could get them to work right and I never could find that Magic Load for them, either.
I don't think that it's a cause for concern as long as the gun is functioning OK.
Nice to see Jack on this Forum.