1911 Firing Pin Wipe. . . Which Spring?

[edwardware]

A question for the 1911 specialists around here. Below is a picture of two cases (the two on the right) recently fired in my Kimber Officer's. To the left is a case fired in the same weapon without charge or bullet (for reference).

The primers fired under full charge show a slight firing pin wipe or double strike. My questions are:

Is this firing pin wipe of double strike?

Is this enough wipe/double strike to worry about (is it going to snap off the nose of the firing pin)?

Is there any way to determine which spring I should replace first (recoil spring or firing pin spring)? The recoil spring is a compound affair in the 3" Kimbers; this one is original with ~1,500 cycles on it. The firing pin spring is also original.

Thanks, Ed

 

[Sunray]

"...firing pin wipe..." The what?
Those are fine. You don't need to change anything.

 

[velocette]

Edwardware;
The recoil springs in Officers model 1911s should be replaced after not more than 1000 rds. Many folks shooting the Officers model suggest every 500 rds. It seems that the springs being short and worked hard will fatigue quickly.
My suggestion to you sir is to buy a couple of sets of Wolff springs

http://www.gunsprings.com/Semi-Auto Pistols/COLT/1911 GOV'T PISTOL/cID1/mID1/dID1

for your pistol and change them.
Yes the primers of your fired cases do show a little firing pin wipe. A more important thing is if your pistol is inlocking that soon, you may be battering the frame with excessive slide speed. Yes you should replace your recoil springs. As an aside, Wolff recoil spring packs usually include a new firing pin spring which you can replace at the same time.
Another item which will slow the unlocking of a 1911 and also reduces felt recoil is an EGW O/S firing pin stop. http://forum.m1911.org/showthread.php?t=13060
Works for me.

Roger

 

[brickeyee]

Recoil spring affect on unlocking is vanishingly small.

The spring is not compressed enough to afford significant force.

 

[1911Tuner]

The recoil spring's effect on unlock timing is zip. That's controlled by the link, and is mechanically fixed. It will occur at the appointed place in the slide's travel regardless of how fast or slow the slide is moving. You can remove the recoil spring completely and fire the gun...and it will function normally aside from returning to battery.

Your tadpole tail is most likely caused by a weak firing pin spring. The firing pin itself may be a bit too long. The spring is the most likely cause, though...and that's the first thing to address.

 

[edwardware]

@ vellocette: About that EGW firing pin stop: do you have one installed in an Ultra Carry? I've been interested in the idea for a number of years, but I don't care to run through another 200 rounds of expensive nuclear tipped ammo re-testing reliability after changing the cocking radius. If you have one installed, about how much radius did you grind in?

@ Tuner: I don't think I would have arrived at that conclusion, but now that you state it that way I see that it's consistent with the 'bullet-barrel friction' theory of 1911 operation. I guess it's time for a Wolff spring kit.

Thanks much for all the replies!

 

[1911Tuner]

Oh yeah. Ned Christiansen proved it several years ago by firing a 10mm repeatedly without a recoil spring in it. Full power stuff, too. No harm done, and there was no indication of early unlocking. Not sure if the bullet friction induced delay was what he was proving...but he did.

 

[velocette]

edwardware;
I have the EGW firing pin stop in all of my 1911 type pistols. One of which is a Kimber Compact Stainless II. Officers frame, 4" barrel. Reliability was not changed in any of the pistols. The radius is very small, more like just a bit more than only breaking a sharp edge. Go to : http://forum.m1911.org/showthread.php?t=93025&highlight=firing+stop For more information.
The only difference was a small reduction in felt recoil and the pistols were a bit more difficult to operate the slide when uncocked due to the difference in mechanical advantage. If I read its history properly, the very small radius of the firing pin stop was John Moses Browning's (Peace be upon him) original design. The radius was added later to ease cocking by manipulating the slide.
By the way, that 1911 Tuner has forgotten more about the 1911 than I will ever know. Good man to listen to.

Roger

 

[edwardware]

@ vellocette and @ Tuner:

Gentlemen, thank you. I appreciate your time and knowledge.