Author Topic: light firing pin hits  (Read 11154 times)

Offline coyote

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light firing pin hits
« on: May 06, 2011, 08:47:10 PM »
guys, i need your insights:

this is about a Stealth i recently purchased. i've been trying different non-plus-P factory loads though it. i found that a number of times i need to use more than trigger pulls to get the round to go off, due to what appear to be light strikes by the firing pin.

below are some of the brass to illustrate what i mean:

-the aluminum blazers show a light hits but appears deep enough

-the federal 9BP case shows the same sort of shallow hit

-most of the rem umc  appear to have been barely struck. on one primer you can see how i hit it twice. i'd say every third round needs a second or third strike. looking at these cases, it appears that some of these primers have flattened out where hit. they look like the firing pin just barely hit them.

regardless of brand, shouldn't they all function correctly in my R9?

what does this all mean?



i've checked the firing pin by holding back the slide and pushing it forward so i could view the tip. looks OK to me. no chips or breaks in it. spring pressure seems normal to me.

i also checked to see that there was enough of the firing pin exposed to the hammer to be able to give it a solid wack. it doesn't look like as much sticking out as i'm used to seeing with 1911s. is it like yours?



have any of you run into this problem?

i do not want to have to ship it back to the factory if i can take care of it myself.

thoughts? ideas? suggestion?

.
if it isn't a rohrbaugh, its too darn big

Offline tracker

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Re: light firing pin hits
« Reply #1 on: May 06, 2011, 10:07:58 PM »

A few of us have experienced this issue. Your photos showed 11 casings; there are ten that I wouldn't have fired: the Blazers and the UMCs. There appears to be some hard primer/light strike hits that can be isolated by switching to the recommended ammo, i.e., Gold Dots, Silvertips, and WWB. The UMCs look to be very suspect as a hard primer problem similar to the Hornady Critical Defense ammo that caused many light strikes before we went elsewhere rather than tolerate the S&B hard primers.

Offline kjtrains

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Re: light firing pin hits
« Reply #2 on: May 06, 2011, 10:12:13 PM »
coyote.  Just a quick question.  Have you tried Gold Dots or Winchester Silvertips?  Be good to know if either one of these or both function reliably in your Stealth.

Some of that that you're showing could be hard primers.  If you haven't tried the Gold Dots or latter, you should; could answer if it's a gun problem.
Let us have faith that right makes might, and in that faith, let us, to the end, dare to do our duty as we understand it.  Abraham Lincoln

Offline yankee2500

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Re: light firing pin hits
« Reply #3 on: May 06, 2011, 11:46:52 PM »
I would definitely try some other ammo brands before I panicked or considered sending the gun back.
I find the Remington UMC to be a very dirty ammo and won't shoot it in my pup.
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Offline coyote

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Re: light firing pin hits
« Reply #4 on: May 07, 2011, 12:52:32 PM »
points taken.

my plan was to put a few cheapie rounds (that i had laying around and wanted to use up anyway) though my R9 to get a feel for the recoil, point of impact, trigger action, required grip tension, etc before testing it with expensive defense ammo.

from what you all are indicating, my problems are very likely due to the crappy ammo i'm using and that i should just by-pass my "plan" and go straight to using the good stuff (and maybe winny's white box).

glad to hear it's probably just my poor choice in fodder (with the possible exception of Fed 9BP, which tracker seems to think is ok and that i happen to have a few boxes of).

i bow to your knowledge and will make an order for ammo today.

thank you all for your help and wisdom.    :)

i will report back when i have more news.
if it isn't a rohrbaugh, its too darn big

Offline Richard S

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Re: light firing pin hits
« Reply #5 on: May 07, 2011, 06:38:35 PM »
WWB is reliable for range work, but it's "dirty" as Hell. Just plan to give your R9 a good scrub when back from the range.
(1963-1967) "GO ARMY!"

Offline coyote

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Re: light firing pin hits
« Reply #6 on: May 07, 2011, 06:45:48 PM »
thanks for the clarification richard. i wasn't sure why folks seem concerned about how "dirty" any particular fodder is, but now i know it's because some folks don't keep their tools clean like they should!

me, i'm OCD so keeping things clean is not a problem, but it is an obsession  ;D

fyi - at everyone's suggestion, i ordered a boat load of gold-dots this morning to feed my new pup.

one more thing: taking your advice to only shoot quality ammo, i thoroughly cleaned and lubed my R9 an hour ago, dug out a half box of Fed 9BP and ran them thru the Stealth. it performed flawlessly. you guys were 100% correct!

.
« Last Edit: May 07, 2011, 06:51:34 PM by coyote »
if it isn't a rohrbaugh, its too darn big

Offline tracker

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Re: light firing pin hits
« Reply #7 on: May 07, 2011, 06:58:55 PM »
You're definitely on the right track, Coyote. Hard primers and the Pup can be a bad match.
« Last Edit: May 07, 2011, 07:29:53 PM by tracker »

Offline sslater

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Re: light firing pin hits
« Reply #8 on: May 07, 2011, 09:54:02 PM »
Coyote,
I have seen strikes like that with my early serial number R9s since Rohrbaugh replaced a cracked slide about three years ago.
Your Remington primers look very much like what my R9 does to Winchester primers.
As long as I stroke the trigger in a single motion, like a defensive gun would be fired in real-life, I have had zero failures to fire.  If I fire the Rohrbaugh like a target pistol with a slow, deliberate trigger pull, there have been a few times when I got a failure to fire and had to pull the trigger a second time.  

Last time I went to the range I fired a selection of WWB, Federal (Federal has a reputation for the softest primers), Speer GDHP (CCI primers),and Fiocchi thru the R9s.  Then I fired rounds from the same boxes in my Ruger SR9.  In every case the primers in the rounds fired from the Ruger had a "normal" appearance, while most of the rounds fired in the Rohrbaugh looked like your Remington rounds.  This indicates to me that I'm not looking at a primer issue.
My next thought was excessive headspace - chamber depth at or above the high limit - but the chamber depth of my Rohrbaugh seems to be very close to the Ruger.  Besides, a chambered round is held by the extractor.  Ditto for the way the extractors hold a round in either gun.  It is difficult to measure headspace and extractor to breech face dimensions without special tools.
Firing identical rounds back-to-back in two different guns says something is different.  For whatever reason the Rohrbaugh is allowing rounds to slam against the breech face, flattening the primer.  So, what looks like a light firing pin strike is actually a flattened primer (without excessive pressure!)
I've been considering sending my R9 back to Rohrbaugh but it fires reliably enough for me to carry it without concern.  

If you do decide to return your gun to Rohrbaugh, please let us know what action they take.

Steve  


Offline tracker

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Re: light firing pin hits
« Reply #9 on: May 07, 2011, 10:20:26 PM »
Steve,

I think you are onto something but on the other hand why would some primers function flawlessly and others flatten? After many conversations with a person in charge of production at Hornady I decided that the ammo and gun manufacturers tend to blame one another. I have read that small handguns like the R9 are very primer sensitive. Many on this forum have never experienced this issue.

One thing I noticed with the bad Hornady primers is that they appeared to be flatter or more flush with the casing whereas problem free primers seem to be indented slightly which alludes to your headspace question. Notice the Federal primer above seems to have a different seating depth than the UMCs. Hornady told me that was one of their proposed solutions.
« Last Edit: May 07, 2011, 10:34:03 PM by tracker »

Offline MRC

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Re: light firing pin hits
« Reply #10 on: May 08, 2011, 07:47:08 AM »
I believe the "fried egg" primers on the R-P ammo is pressure related, but i am not really sure.

I have a Colt Pocket Nine which would do this with about 60% of the ammo I tried.  The same ammo worked in several other 9mm I fired it in  and the fired cases looked normal.  It would do it with my reloads also.  I used 4 different brands of primers with the same results.  By lowering the powder charge approx 5% the primer problem went away.

My conclusion was that I was getting excees pressure in that gun and not the others for some unknown reason.  My first R9 exhibited this with one brand of ammo also, but I did not have that pistol long enough to draw any conclusions.

These are the only two guns I have ever seen this on.  I truly think it is gun/pressure problems and not primer related.

Offline RickP

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Re: light firing pin hits
« Reply #11 on: May 08, 2011, 11:11:32 AM »
Speer makes Lawman TMJ as an affordable practice round to complement their GDHP rounds. Ammo-to-Go sells them for about half the price of Lawman Gold Dots. This "system" lets you practice with what you carry, at an affordable price.

Rick

Offline tracker

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Re: light firing pin hits
« Reply #12 on: May 08, 2011, 11:47:39 AM »

Good point, Rick, about staying consistent with ammo. There seems to be three possible variables in this issue: gun; primers; and pressure. Anything that can be done to isolate the potential problem will help to achieve consistency. On reason I thought it was the primer was because I could tell that different primers were used in different lot nos. with Hornaday. Those that appeared to be flat or flush would pancake and those primers that were recessed would fire normally. I finally gave up on all Hornaday because of this inconsistency. Maybe their pressure varied with lot nos. also even though it was within SAAMI specs.

Offline MRC

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Re: light firing pin hits
« Reply #13 on: May 08, 2011, 12:19:16 PM »
I spent a lot of years playing with Benchrest rifles and Long Range Precision rifles ,so I have done alot of reloading.  Observing fired primers is one of the few ways for someone outside of a lab situation to gauge pressure, and it is also very unreliable.  Variations in brass hardness, primer pocket size, and primer pocket depth are just a few of the variables.

Other factors affecting pressure spikes are barrels, chamber dimensions, bullet size and roundness, and bullet hardness.  With what I have seen with my two R9's plus pictures and conversations with other R9 owners, barrel variances could well be a problem but I have no way to gauge it and I am having no problems with my present Rohrbaugh pistol.

One thing for sure, a load that is perfectly safe in one rifle will practically blow another person's gun up.  I would think the same would hold true in pistols.  It is not as critical as pressures are much lower and the spikes of a much shorter duration. The trouble is we have no way to measure it.
« Last Edit: May 08, 2011, 02:24:16 PM by MRC »

Offline sslater

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Re: light firing pin hits
« Reply #14 on: May 08, 2011, 01:10:21 PM »
Tracker,
Interesting point about avoiding Hornady because of inconsistency.  Hornady has to buy primers, unlike Speer (CCI), Remington, Winchester, Federal, and Fiocchi who manufacture their own primers.  So Hornady - a first rate ammo manufacturer - is at the mercy of the supplier(s) of the cheapest component that goes into a cartridge.  The primer.  A $.03 item at retail.  Brass costs about $.20  Think of all the dimensions that can stack up in just the cheap primer and brass, and it's amazing that anything works!  I marvel at the process control the primer and brass manufacturers have achieved.  They surely cannot afford to spend much time on inspection of 3 cent and 20 cent parts.  

I have prepared hand-loads with a number of different primers, identical new brass, same brand of bullet and by-the-book starting quantity of three different powders; fired them from the Rohrbaugh and my Ruger SR9.  The results were the same as with commercial ammo.  The Rohrbaugh showed flattened primers, the Ruger showed normal-looking primers.  I'm pretty sure that those starting powder loads are not causing high pressure.  That brings us back to something in the dimensions of the gun itself.    

The 9 mm round runs at high pressure - nearly as high as the much younger .40 S&W.  I have a number of .40's and I've found the duty- size pistols are more reliable that the compact ones.  I have only two 9mm pistols, and it looks like the duty-size gun tolerates most anything but the little gun (Rohrbaugh) has to be near perfect in order to be reliable.  My bottom line is to find ammo that runs reliably and stick with it.

I don't know if this helps or confuses Coyote, but my two posts on this thread cover pretty much all that I've learned about the care / feeding of a Pup.  8)


Steve