Author Topic: Flat Primer Strikes?  (Read 5336 times)

Offline st_albert

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Re: Flat Primer Strikes?
« Reply #15 on: May 15, 2007, 07:47:05 PM »
I have noticed the same kind of appearance.  I believe I only noticed it recently, when using some handloads, though I can't be sure it didn't occur also with factory ammo.  I will check into that, next time.

The handloads are 115-gr lead semi-wadcutters from Penn Bullets, and clock at about 1050 ft/sec out of a 4.5" barrel.

However, in my case, it is definitely NOT due to high pressure, because:

1) the handloads were purposely made to be on the mild side;

2) the same ammo when fired in a different pistol gives normal looking primers; and

3) the outer rim of the primer is not flattened (as it is with high pressure).  Only the area of the firing pin strike, which looks as if it has been smeared over.

By the appearance, I would guess it's being caused by the primer extruding back into the hole in the breech face, then being wiped down as the barrel drops during cycling, dragging the case head downward across the breech face.

Ironically, these handloads have had problems feeding in pistols such as the Walther P1, which is of an older military design, yet they are at least as reliable as anything I've tried in the Rohrbaugh.  No failures to feed, and only the occasional stovepipe.

The appearance of the primer is kind of spooky, though.  I've got a picture but I can't figure out how to post it, since I have no website to host it on.

Albert

Offline theirishguard

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Re: Flat Primer Strikes?
« Reply #16 on: May 16, 2007, 10:30:34 AM »
very interesting.............. ???   Tom
Tom Watson, DVC , Quis Separabit ,  Who dares wins, Utrinque Paratus

Offline Hk-Itch

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Re: Flat Primer Strikes?
« Reply #17 on: May 16, 2007, 08:06:03 PM »
Yup, that's exactly what I was happ'n to me.  My last range session out I couldn't find any primer hits like that though.  Doesn't mean they were'nt there, I just didn't find any.  That was also after I swapped out the mag springs with the stronger ones.

Offline st_albert

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Re: Flat Primer Strikes?
« Reply #18 on: May 19, 2007, 08:36:29 PM »
Just a quick update.  I had the opportunity the other day to fire a few rounds of WWB.  The primers weren't smoothed flat, but the firing pin indentations were oblong -- not round.  This seems to indicate that the case is being pulled downward as it is ejecting, before the firing pin has had a chance to retract.  Maybe that is by design?

Albert

Offline BogoRatta

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Re: Flat Primer Strikes?
« Reply #19 on: June 11, 2007, 08:02:42 PM »
Just purchased a R9S yesterday - First trip out I didn't suffer any FTF in 75 rounds of various brands but I did have the flat primer strike issue. Has anyone found a solution to this problem... this happened with Federal, Remington and Speer Gold Dot (all standard pressure - not +P)
Lookls like the primer is balloning and then being sheared flush by the breech as the pistol cycles.  I aligned the extractor marks at 3 o'clock in these pics - so the breech is wiping the brass upwards.


Also this is evident in the 2 spent cartridges supplied by the factory.


One more thing is I noticed some alarming wear on the alloy frame!
« Last Edit: June 11, 2007, 09:16:30 PM by BogoRatta »

Offline Hk-Itch

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Re: Flat Primer Strikes?
« Reply #20 on: June 12, 2007, 05:51:27 PM »
Mine has the same wear.....appearently normal.

Offline st_albert

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Re: Flat Primer Strikes?
« Reply #21 on: June 15, 2007, 09:54:12 PM »
@bogo-rata:  My flat primer strikes look just about like yours.  There is a circular pattern that just matches the diameter of the hole in the breech face through which the firing pin passes.  Coincidence?  I think not!

I am, for the present, considering that the "flat primer" issue, as well as the "drag" issue for WWB cartridges, is harmless.  Rest assured I will post if I see any indications to the contrary, and I hope others will do so as well.

[Ironically, CCI primers which were used in my reloads that exhibited the "flat primer syndrome" are supposed to be HARDER than the Winchester primers that showed "firing pin drag" indentations. :shrug:]

Offline BogoRatta

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Re: Flat Primer Strikes?
« Reply #22 on: June 16, 2007, 08:22:07 PM »
st_albert - excellent analysis! The primer case is deforming into the firing pin hole and then being sheared off as the barrel drops.
Today I methodically fired a variety of ammo and collected the brass from each shot.  I still saw the 'flattened primer' or 'primer shearing' to a greater or lesser degree with every brand.  Also I noticed that on the primers of the 2 failures to fire during the session, there were crescent shaped marks in the primer cap.  Likely to have been caused by the sheared off primer metal lodging in the firing pin channel and preventing the firing pin from striking correctly.  See photo for enlarged view of the 2nd 'dud'.






I am new to this forum and to this pistol.  Do any other owners have a similar issue?  Is this a common thing with these pistols?  Any help/comments would be appreciated before I return my new little loved one back to Rohrbaugh.
Thanks in advance,
BogoRatta

« Last Edit: June 16, 2007, 09:41:26 PM by BogoRatta »

Offline Hk-Itch

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Re: Flat Primer Strikes?
« Reply #23 on: June 16, 2007, 10:38:47 PM »
Well.....apparently not an isolated incedent.  Great pics guys!  Thats exactly what I had experienced and seen.  Again, its not been an issue so far as reliability and function.  My solitary issue was with the weaker mag springs and now corrected.  

Offline BogoRatta

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Re: Flat Primer Strikes?
« Reply #24 on: June 16, 2007, 11:57:19 PM »
Thanks for the feedback Hk-Itch...
The frame wear; you are absolutely correct on...it seems normal, after I shot the R9 some more today...  However, those loose shards of crescent shaped metal from the primer could cause you to angrily 'click' at the BG when the last thing he should hear is a BANG!
On a positive note - the 'lil gun has fed many brands of ammo flawlessly after a only short break in period. (apart from deliberate limp-wristing to push the envelope of the R9's reliability)
I am interested to know if Rohrbaugh have a fix for the main topic of this thread, before I throw away another $50 in shipping...
(all that test ammo wasn't cheap BTW)
Cheers and Good Shooting,
BogoRatta
« Last Edit: June 16, 2007, 11:58:23 PM by BogoRatta »

Offline riffraff

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Re: Flat Primer Strikes?
« Reply #25 on: June 17, 2007, 10:47:56 AM »
BogoRatta,

The wierd primers are pretty common with my 2 R9's and I have decided that this gun pushes the envelope so much with the long freebore and it's semi locked breech design and the obvious difficulty of designing a gun this small that fires 9mm and many other aspects of this gun I decided to quit worrying about all the various issues as long as mine are reliable.

Since you are haveing FTF issues I would definately sent it back and definately send your excellent photos to help the R bros.  correct your gun and probably help them help others as well.

I bet I got you beat on spending money on various brands of ammo in testing my R9's. :)

Mike
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FCSA Life Member

Offline BogoRatta

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Re: Flat Primer Strikes?
« Reply #26 on: July 11, 2007, 10:57:12 PM »
OK..   returned pistol to R....  and rcvd it back today.....
Service was A1+
spoke to the main man (Karl)  WOW!!!
Exremely helpful!!!!  (and he is a courteous gentleman)
I have to say how impressed I am at such personal attention from the manufacturer/owner.....anyone reading this should just go ahead and buy one....the best mini 9mm I have had the pleasure to own/shoot...
I will fire my lil mini next wkend and report out!
« Last Edit: July 11, 2007, 11:10:50 PM by BogoRatta »

Offline DTM_39

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Re: Flat Primer Strikes?
« Reply #27 on: July 12, 2007, 07:52:37 PM »
Service is A-1
NRA LIFE MEMBER

Offline Richard S

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Re: Flat Primer Strikes?
« Reply #28 on: July 12, 2007, 08:27:44 PM »
BoboRatta:

If I have not welcomed you to the Forum, I do so now.

Karl and Eric Rohrbaugh are true gentlemen who are dedicated not only to providing the finest quality handguns but also an extraordinary level of customer service. I've always found it a real pleasure to do business with them.
(1963-1967) "GO ARMY!"

Offline BogoRatta

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Re: Flat Primer Strikes?
« Reply #29 on: July 30, 2007, 10:10:58 AM »
Thanks for the welcome Richard!
Yesterday, I finally got the opportunity to take the pup to the range .  I fed it 5 clips of Speer Gold Dot and it digested every one without a hiccup.  I am no sharpshooter, but was impressed when I put 5 rounds in a 3 inch ring @ 7 yards (nearly perfect but for that one flier!).
Cheers!
Bogo