A friend of mine has a new XD40. The firing pin strikes are strange looking. Any ideas? Is the pin coming in from an angle? or something else?



I have never seen a pin strike like this.

If you have the pistol look at the firing pin hole, or could be starting to eject too quickly just a guess.

Needs heavier recoil spring perhaps

It's often called 'primer wipe' and is very common with striker-fired pistols - even normal. The striker is still in contact with the primer when the case hits the ejector. The ejector pushes the case sideways through the ejection port and the striker wipes across the primer. It's more common in striker fired pistols due to the increased mass of the striker assembly.

If you want to get rid of it you either have to speed up striker retraction or slow down slide velocity. For the former, make sure everything is clean, dry, and straight - no lube. For the latter, consider a heavier recoil spring as the last option - there are too many potential problems and as long as the wipe continues to be minor I would just put up with it.

Thanks for that explanation. I’ve seen this exact same indentation on cases from my Kahr pistols and also a friend’s Kahr, but everything else was normal so we never gave it any thought.

Actually, primer wipe is caused by the primer still being in contact with the striker when the barrel is cammed down as it unlocks from the slide, which occurs in the very beginning of the rearward travel of the slide. It will leave a tail on the primer pointing straight up, as the case is pulled downward on the breech face. Make a mark in the case head with a sharpie and index it top dead center and you will see the tail pointing up toward the mark. It is not caused by the firing pin being in contact with the primer at the time of ejection.

This is correct. It's also pretty normal for many brands of pistols especially with higher pressure rounds like 40 S&W; nothing to be concerned about in that picture.

K1500, You're 90% right.

Primer wipe can be caused by either the ejector or barrel tilting, but is most cases it is barrel tilting as you said. I think my brain rolodex stopped on the first card and the cards were out of order.

The remedy is still the same - speed up striker retraction or slow down the slide.

As always, JOG is spot on (as is k1500).

There is another very common cause of this...a very dirty firing pin channel. Striker fired pistols should have their FP/Striker channel cleaned from time to time as the most common issue encountered with SF pistols is a failure to fire due to a soft or retarded FP strike. My first recommendation would be to pull the slide apart, clean the dickins out of the FP channel, lightly oil, and reassemble...99% chance this problem will go away.

Do not oil the striker channel, that's the best way to make sure you have more issues in the future. Leave it clean and dry.

Yondering,

Thanks for catching that...I think my brain was on auto-pilot when I typed that. The FP channel on most striker fired pistols should be kept dry!

Thanks for the original question and the explanations. I have noticed the same with my XD40 but as it worked I didn't give it much thought. I did notice the marks went away when I replaced the recoil spring but they came back a couple of springs later. I have not noticed any similar marks with my other striker fired pistols but then I only noticed the marks on my XD after clearing a stove pipe which caused me to look at other casings.For curiosity's sake, I will have to look at the cases of my other striker fired guns and see if they do it too.

GG - 10-4. I wasn't sure if you meant to just oil everything else, but figured I'd clarify for those who didn't know.