PM9 Scorched Casings (pic)

[Mudcat]

I have seen several when picking up brass at the range. I've never noticed it on any of my own cases unless they have been reloaded several times and have become harder. From working the brass by too many resizing and heat cycles. But it usually shows up in my rifle rounds. If I anneal the case it stops and looks normal for 3 firings or so.

Does it do it with factory ammo or once reloaded brass?

You got some great possible reasons why from the guys on here.

[CJB]

I agree with CJB. You must be a reloader.

Actually... I've been in the position to oversee a large commercial reloading operation, all done with "range brass", our own cast bullets made from (you guessed it) range lead. We went from "drop a pig of tin or wheel weights in the mix every so often" to "measure the hardness" under my watch. I developed large scale decapping mechanisms that worked for even military primed brass, and never touched the primer with a "poker-outer" piece. We automated some Dillon machines... mostly used AmmoCrafter linear machines and Dillon indexing machines (the old Dillon, I forget the machine... the 1000?). It was a nice brain teaser for the years I worked there. Also came up with a way to sort cracked brass out automatically when coming out of the tumbler and onto the sorting screens. Everything had to be automated as much as possible, to keep labor costs low, and volume high. The range sold a lot of its own reloads for range-only use. Imagine a Friday night with 25 to 30 shooters, each using two or three boxes, Saturday with 50-75 shooters doing the same. Maybe 25-30 again on Sunday afternoon and 20-25 a day from Tuesday thru Thursday. So figure 200 shooters a week, times two boxes, times fifty rounds. Conservatively, thats twenty thousand rounds a week, just past a million rounds a year. There were better and slower times of course, but still, I think I qualify as a reloader!!~

Range brass is the worst to reload. Varying sizes, varying quality, varying wear, varying hardness... its a real pain in the butt.

His were Federal factory... but they might have been over "taper crimped" at the factory. Eventually, the case does expand and seal - its just a matter of how much gas will flow backward before it does. Not much, less than a puff... just enough to smoke darken things.

[redbeardmcg]

I got a response from Kahr:
"I have spoken with our head gunsmith and showed him your photograph and that is perfectly normal for our firearms. What you have described in no way will effect the accuracy, safety or functionality of the weapon. I hope this information helps."

To clarify, the rounds pictured were factory 115gr Federal. I did verify the burn mark on a box of 115gr WWB as well as 124gr +P gold dots.

Though I'm not happy with the "don't worry about the abnormality, it's benign" response, I will say that the gun still feeds well, ejects well, and goes bang every time so I'll just keep an eye on it to see if it worsens.

Thanks for the feedback and information, you guys are a wealth of great information!

-Ryan

[jocko]

well u ask them, and u got ur answer. now u have to decide to accept it or move on. Personally I thinmk ur malking a mountain out of amolehill, The 3 most important criteria of ur gun that u mentioned is perfect. trust what kahrs tells u, if down the road it goes south, they will make it right. Would not have bothered me in the slightest, but that is just me.

[PYROhafe]

I would mark a few cases with a Sharpie from rim to bullet and load them with the mark on the extractor side. My guess would be that the opposite side is getting scorched by residual blast from the chamber as the case rotates out to the right. This is probably going to change as the recoil springs weaken a bit more.

In my flash stills from firing video there is a lot of flash coming from the ejection port and sometimes inexplicable places aft of the ejection port. Timing changes as the spring takes a set and varies with the burn rate of the powder.

Wynn

Where can I see those pics Wyn????

[TucsonMTB]

Where can I see those pics Wyn????

Here is a link to one of his threads that contains this picture.

[wlfman40]

Had the same brass scorching when using S&B in my CM9, it was flawless and IIRC I have had that happen with my glock. My Kahr remains accurate and reliable for what its worth.