Help, PTR 91 FTE


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HGUNHNTR
March 24, 2008, 10:29 AM
Hello gang, I took my new PTR 91 (.308) out this weekend for the first time. I cleaned it thoroughly before its maiden journey and was really excited to shoot it. I put 40 rounds of Lithuanian surplus through it, and 30 rounds of magtech ammo. Then..........I experienced the malfunction. The gun would fire, re-cock, and fail to extract the spent brass casing. It was extremely difficult to pull the charging handle back to manually eject the casing. When I was able to get the charging handle back it ejected the casing normally. I took the bolt apart, cleaned it, and re-assembled it. Any ideas what would cause this FTE?

The good news is, before the fte it shot extremely well. Much lighter recoil than I expected, and very good accuracy. I just need to get it running again!

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ocharry
March 24, 2008, 02:43 PM
so did you clean the chamber?? was this litho stuff really dirty or sooty??

on these guns the extraction is pretty violent,,and the extractor will actually tighten up as extraction pressure increases,,, i have seen the head ripped off cases the have gotten stuck,,and i would recommend a broken shell extractor in your kit for this rifle

make sure the flutes in the chamber are clean and free from oil and dirt,,,,some of the surplus stuff uses a tar to seal the bullet in the case,,i can't remember which one it is ,,, could be litho,,,,and this will cause extraction probs.

could have broken the extractor or extractor spring but i wouldn't think so,, pull the carrier out and look at the end of the bolt head,,,extractor will be on the end of the bolt head and it should be tight ,,slide a empty case under it and see if you have a prob with it

did you try it again???

ocharry

TexasRifleman
March 24, 2008, 02:51 PM
The Lithuanian doesn't use a sealant, not sure about the other one.

ocharry
March 24, 2008, 03:08 PM
yep i wasn't sure,,, but i remember the guys on the military forum talking about the tar sealer one of the countries used causing a problem with extraction

ahh just had a light bulb come on after reading you OP,, again

which one of the shells did yo have the prob. with???

if it was the magtech it could have been the soft(and thinner walled) civilian brass and higher pressure,,, could be getting stuck in the flutes of the chamber and causing the extraction prob....not sure about the PTR rifles,,, but it's not a good thing to shoot regular 308 stuff in mil-surp rifles,,,something about pressure and thicker brass on the mil-surp cartridges

just another thought while i was here

ocharry

TexasRifleman
March 24, 2008, 04:43 PM
if it was the magtech it could have been the soft(and thinner walled) civilian brass and higher pressure,,,

You might be onto something there. Didn't think about that but it might rip that bolt back so fast the extractor can't hold on.

Would make sense I suppose.

jwxspoon
March 24, 2008, 05:35 PM
I've had light strikes on mine; occasionally the bolt doesn't seem to close all the way. I've often wished these rifles had a forward assist like the M16.

Never had extraction problems.

jw

MM
March 24, 2008, 08:29 PM
Mine did that 2 or 3 times wth aussie AND Hornady light mag when new. I let it cool abit and clp'd the heck out of it. I ran it on the wet side for the next several mags. It broke in and there have been no probs since (4+ years).
MM

HM2PAC
March 24, 2008, 08:38 PM
The most common problem with these rifles is overzealous lubrication. There should only be a light amount of oil/grease on the moving parts only. When you think you have cut it down to the bare minimum, you probably still have way too much

The mechanism of action is direct blowback. Lots of crud is going to be in the chamber. Oil or grease will "Gum-it-up".

You should also invest in a good chamber brush. Make sure the flutes are clean when you are done.

MM
March 24, 2008, 08:44 PM
Hospitalman,
Old "PH" here, I believe you are correct, but after the weapon has broken in. My ptr runs pretty dry these days, but when new and it was hot it would sieze. The light CLP seemed to let it "teeth" sufficiently until the stiffess of the new wore-off.
I hope you enjoy your liberty like I used to, Mate.
MM

stubbicatt
March 24, 2008, 09:55 PM
Due to the design of this rifle I believe it highly unlikely that you will have a case head extractor goove/rim torn off by the extractor. The force of the case exiting the chamber, floating as it were on a thin film of high pressure gases, is what causes the bolt to unlock and begin to cycle. The extractor holds the case head firmly on the bolt so that it may be acted upon by the ejector. This is different fundamentally from the cycling of a gas operated action, where the case may be fully obdurated while it is acted upon by the cycling of the action. Here it is the case itself which cycles the action.

I'd first look at dirty fluting in the chamber, clean it properly with the HK flute brush, and clean the chamber well, leaving it totally dry for the next go round. I would make sure that the spring loaded lever that holds the bolt head to the bolt carrier when the gun is in battery has proper lubrication, and a small smidgen on the rollers and locking piece.

Another thing to examine is to assure that the ejector lever is riding properly into the slot in the bottom of the groove in the bolt head. If not a dirty chamber, it is conceivable that the ejector is not riding high enough in the bolt head to eject cases reliably, and what you are receiving is simply reinserting your fired cartridge into the chamber. Generally this cause has the additional symptom of stripping a fresh round out of the magazine, which dislodges the spent casing from its repose in the bolt face, and jamming the spent casing between the bolt carrier and the trunnion near the top of the trunnion, leaving you with an open bolt jam and a misfeed. Generally you have to drop the magazine and cycle the action to start over when this happens.

My bet is on the dirty chamber, fouled with tar or oil or both.

Mortech
March 24, 2008, 10:07 PM
I had the same issue on my Cetme when I first got it , it was the softer commercial brass loads . Luckily I didn't get a seperated case . BTW shooting reloads in a Cetme/HK type of weapon is highly NOT recommended due to the soft brass issue .

HGUNHNTR
March 24, 2008, 11:27 PM
Thanks All!!! The malfunction was with the .308 win magtech stuff, not the 7.62x51 lithuanian. (the lith was good looking ammo) I cleaned the rifle before firing, and very lightly lubricated it. I am a firm beleiver in counting the overall lubrication of a rifle in number of drops, not squirts. I am about to pull the bolt and check the chamber, however I think the ammo was probably the culprit.
Again, thanks to all who have responded, your collective brainpower is greatly appreciated.:D

Onmilo
March 25, 2008, 08:56 AM
MagTech ammo, Bleh.
My PTR 91 choked its way through the first forty or fifty rounds.
I had a mix of Portugese and South African surplus ball on that first outing.
At first I thought it was the South African ammo but by the time I loaded the forth magazine it started running fine.

It gobbles its way through everything I have fed it since including Chinese steel case ball ammo.

New guns and stiff springs, I think everything needs to get settled before they run 100%.

HM2PAC
March 25, 2008, 06:13 PM
So far my PTR loves the handloads.

I've not heard anywhere that reloading was not recommended.

Winchester, Remington, Federal, all of it cycles just fine.

Feanaro
March 25, 2008, 06:41 PM
Due to the design of this rifle I believe it highly unlikely that you will have a case head extractor goove/rim torn off by the extractor. The force of the case exiting the chamber, floating as it were on a thin film of high pressure gases

This works until the brass doesn't float on that thin layer of gas. The brass sticks to the chamber walls and something has to give, so the brass and case head go their separate ways. Ask me how I know...

This is only a problem with thin commercial brass and bad headspace though. The PTR is not likely to suffer from this issue, being well made. Century CETMEs, on the other hand...

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