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bumpfire
09-08-2009, 11:35 AM
My PM9 black has .028" firing pin protrusion and my other three 9mm Kahr's have .032". I have several Glocks that have .042" protusion. Is there a SAAMI spec for auto pistols? Anyone know what the Kahr spec is?
I cleaned the channel of the .028" PM9 and it did not change.

WMD
09-09-2009, 12:05 PM
Are you having an issue with your gun? I think SAAMI specs are only for ammunition and chambers. Not an expert on this topic but I think I am correct.

How are you measuring the protrusion?

bumpfire
09-09-2009, 03:08 PM
No issues but it is my full time carry gun and that it has less protrusion than my other Kahrs I have some concerns. I am measuring with feelers guage. I will get a guage from Midway on my next order.

jocko
09-10-2009, 10:57 AM
No issues but it is my full time carry gun and that it has less protrusion than my other Kahrs I have some concerns. I am measuring with feelers guage. I will get a guage from Midway on my next order.


ur not having one issue then stop worry about what other guns have. the designs are not all alike and there is no SAAMI specks for what u are referring to. If it ain't broke, don't fix it.

Just shoot it like u stole it...

jocko
09-10-2009, 10:58 AM
No issues but it is my full time carry gun and that it has less protrusion than my other Kahrs I have some concerns. I am measuring with feelers guage. I will get a guage from Midway on my next order.


ur not having one issue then stop worry about what other guns have. the designs are not all alike and there is no SAAMI specks for what u are referring to. If it ain't broke, don't fix it.

Just shoot it like u stole it...

If u have concerns, call kahr CS and discuss it..

bumpfire
09-10-2009, 02:16 PM
I guess you may be right but because it is my carry gun I would like to be sure. I will call Kahr and try to get their spec. I would think all Kahr 9mms should be the same even all calibers are the same.

jocko
09-10-2009, 02:20 PM
I would think that would be right also, U might just have them also send you a new striker firing pin. Keep us posted. I doubt if you will get any specs from kahr though.

bumpfire
09-11-2009, 09:49 AM
I got a reply this morning. They said if no light strikes not to worry about it.
That makes me think it is never an issue unless it chips or breaks.
I think I am OK and it will not wear shorter.

jocko
09-11-2009, 03:19 PM
I got a reply this morning. They said if no light strikes not to worry about it.
That makes me think it is never an issue unless it chips or breaks.
I think I am OK and it will not wear shorter.

HELPS ANY i HAVE 24,750 ROUNDS through my pM9 and still the original striker pin, and still the original extractor, and extractor spring, and original ejector. I replaced the standard striker spring with the wolffs 5# striker spring many thousands of rounds ago.. Also the original slide lock lever little springs on the left side of the grip.

If one is careful in his cleaning techniques, one should never have to replace any of the above IMO...

mr.72
09-14-2009, 09:35 AM
there must be a spec. i hope someone finds out. i suspect this may be part of the light-strikes problems people are having.

bumpfire
09-17-2009, 08:20 AM
Kahr customer service has not answered my question of what the spec is.
I think I am just stuck with figuring it out for myself. I measured three of my Kahr's at .032" and one is .028" so my guess is spec is .032" with a tolerance of +_ .004" or if less my .028 is out of spec.
I have seen on other threads that they will suggest a user try different brands of ammo if they get light strikes. I think that is unacceptable as I think a firearm should function with all brands of ammo that are in SAAMI specs.
The extractor will hold the round tight to the breech face so even a loose chamber or short case should fire 100% of the time which is required of a firearm.
I think there is a SAAMI spec for protrusion as it becomes part of the chamber but I can't find it. It is obvious to me that every manufacturer has a spec but Kahr is just not sharing theirs for some unknown reason?

jocko
09-17-2009, 03:21 PM
bumpfire; PM sent...

bumpfire
09-21-2009, 12:48 PM
Over the weekend I measured two of my 4 Kahr strikers and the PM9 in question was .010" shorter. The .010" shorter was from the tip to the shoulder. The service department said not to worry if it works but offered to send a new one if I wanted. I wanted and thanked them for going the extra mile.

mr.72
09-22-2009, 03:43 PM
There's a doc on the Brownells web site that suggests .050" to .060" is the right amount for a center-fire pistol.

BROWNELLS : GunTech : How Does It Work? Brownells Firing Pin Protrusion Gauge - World's Largest Supplier of Firearm Accessories, Gun Parts and Gunsmithing Tools (http://www.brownells.com/.aspx/lid=10379/guntechdetail/How_Does_It_Work__Brownells_Firing_Pin_Protrusion_ Gauge)

However, the primer indent needs to be (according to my informal survey on the internet) about .016" and the protrusion of the firing pin/striker needs to be sufficient to make such an indent, and therefore the protrusion, when more than enough to make such an indent, is not the primary factor in light strikes. So the question needs to address the headspace and other geometry of the chamber of the pistol as well as the striker protrusion, striker spring energy and mass of the striker itself since it is the momentum of the striker that causes the primer to ignite. Drag in the striker channel could have a major effect, misalignment of the striker with the hole in the breech face could have a huge effect, or if the striker gets bent then it would obviously have an effect.

I suspect that Kahr strikers are on the short side in general and I find it interesting that they are, maybe anecdotally, .010" shorter than Glock and .018" or more shorter than the standard protrusion spec for "center fire pistols" that I found on the internet. I don't have an Armoror's Handbook or such a reference to check, but it could be worthwhile. However I think the problem is not so much the protrusion as it is likely other issues related to light strikes, more to do with manufacturing tolerances, which include the striker dimensions, spring rate and dimensions, striker channel finish and gunk, alignment, etc.

bumpfire
09-23-2009, 07:59 AM
Thanks so much for the info.

The .010" is how much shorter my black PM9 than my other three Kahrs. The reason I am getting a new striker is that I could not find any spec. on protrusion. Kahr customer service said they can not give out that information.
Because it is my full time cary gun I just want to be sure.:)

mr.72
09-23-2009, 09:45 AM
The cynic in me thinks that the reasons Kahr CS "can't give out that information" is either:

a. Kahr customer service reps do not have access to that information -or-
b. If they gave out that information, then it may reveal how many manufactured guns have out-of-spec strikers, causing a ton of requests for new strikers.

jocko
09-23-2009, 11:27 AM
The cynic in me thinks that the reasons Kahr CS "can't give out that information" is either:

a. Kahr customer service reps do not have access to that information -or-
b. If they gave out that information, then it may reveal how many manufactured guns have out-of-spec strikers, causing a ton of requests for new strikers.

bottom line it it works don't screw with it..

mr.72
09-23-2009, 01:51 PM
bottom line it it works don't screw with it..

Yeah, or if it doesn't work, then you're screwed.

bumpfire
09-23-2009, 03:47 PM
The supervisor had the information but could not release it.

I have 3 Kahrs that read .032" with a feelers guage.
If the new striker is .032" I will call that the spec.
I ordered a protrusion guage and will recheck all four and post what it is.

bumpfire
10-01-2009, 07:06 PM
I got my Protrusion guage today and measured all 4 Kahr's. They measured:
PM9 black with new striker .037
PM9 stainless .037
P9 .037
T9 .043
I am very happy and case closed.

gman
01-14-2011, 10:55 PM
http://kahrtalk.com/showthread.php?t=4927