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Pelase explain why "striker drag" is a problem? Login/Join 
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I have P365's and P320's that I use for training and have had zero problems with them. I have also fired many different firearm platforms over the years, many of which mangled the spent brass. I see and hear people talking about striker drag, and I can't understand why with soft metal casings it is a problem when it occurs. Is there really a function problem, or is this a nothing burger?

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I am no metallurgist or a firearms engineer, so this is just a WAG. I accept if my ramblings are completely wrong.

Since the pistol starts unlocking before the striker can retract, the tip is being dragged along the primer face vertically. That's stress in a direction perpendicular to the normal direction of impact. Many of my casings show drag all the way to the edge, which means the primer tip probably dragged across onto the harder brass primer pocket. That might be inducing more stress than dragging across a softer primer face, but it's also later in the cycle, so maybe not. I don't know if the lateral force being exerted is enough to worry about. Sig says no, a portion of the interwebz screams yes, mainly because tips have broken in 365's and not in other micro 9's.

I had to send my 365 back for an extraction issue, and they replaced my striker while it was there. I have no idea if it was because it had one from a bad batch (identified via S/N?), or because they saw it was dragging significantly (at least, significantly more than some photos I've seen from other 365's). It still drags, and it expect it will continue to do so unless something else is changed. Maybe a shorter striker tip or a heavier return spring. But either of those would probably impact reliability.

This message has been edited. Last edited by: JAFO,

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Posts: 5181 | Location: S.A., TX | Registered: July 20, 2006Reply With QuoteReport This Post
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Same disclaimer that JAFO uses applies to myself.

I don't have any experience with the P365, but I have owned/ shot multiple expamples of several classic P Series pistols, P220, P225, P226, P229, and SIG Pro...and everyone of them showed this so-called "striker drag" or "primer drag" (years ago when the issue was discussed on this forum it was frequently referred to as "primer swipe mark" or "firing pin swipe" or some such variant.

Perhaps there is some P365 design characteristic that makes primer drag marks more of a problem than with the classic line...but I suspect that, in a rush to judgement on the cause of the infrequent striker breaks, some find it convenient to point towards the marks.

Perhaps there was a striker design flaw, or perhaps a small batch was improperly hardened or...

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Posts: 4320 | Registered: August 21, 2006Reply With QuoteReport This Post
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JAFO and MDS for the win. This is nothing new.........


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Posts: 32680 | Location: Logical | Registered: September 12, 2004Reply With QuoteReport This Post
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