Survivalist Forum banner

21 - 40 of 49 Posts

·
What hell, pay attention
Joined
·
7,910 Posts
I have been thinking about this (I'm at work) and I think she is just not going all the way into battery.

Charging that rifle requires considerable effort, not sure if the recoil spring is the culprit. So now I'm going to take apart and polish every working surface in the bolt group with polishing wheels and jeweler's compound.
You are "slapping" the charging handle from its locked open position when youre charging the gun, right?

If you are easing the bolt forward to chamber the round, you will get the exact mafunction you are describing.

The way you charge the HK's is to either slap the charging handle from lock, or pull the charging handle fully rearward, and release.

Anything else, and you will likely get that malfunction.
 

·
Banned
Joined
·
1,672 Posts
Discussion Starter #22
No, initial charge (the one that fires) is a slap. I turned her over and let the charge handle go from a full rearward position, not slap but just as far, and the carrier isn't going QUITE into battery. slight push with my fingertip and she goes the last maybe 16th of an inch.

Where in this platform do I polish to smooth that particular bearing surface?
 

·
Banned
Joined
·
1,672 Posts
Discussion Starter #23
I just turned her over again and the amount of out of battery is EXACTLY what you get when the charging handle folds down.

Fold back up without pulling, and she is out of battery.

I push forward on the carrier in the ejection port slightly, and hear an audible clunk, and she seats.

something somewhere needs polishing.
 

·
What hell, pay attention
Joined
·
7,910 Posts
I had two HK91's and a MP5, and all would do exactly what you are experiencing, "if" you didnt slap the charging handle free from lock, or let the bolt go forward hard from full rearward extension. Thats how they are meant to work.

Id try that before I started trying to "polish" anything. If its not working beyond their so called break in period, Id send it back.
 

·
Banned
Joined
·
1,672 Posts
Discussion Starter #26
All right, AK. I'll switch to a little stouter ammo, and use grease inside the carrier. Past 300 dollars, I mean rounds, if it is still a one-shot wonder, I'll trade it to you for an AK :) .
 

·
What hell, pay attention
Joined
·
7,910 Posts
Cant help you on picking now to choose a $1 plus a round gun to have to try and break in. Thats on you. :)

If youre using proper ammo, it should cycle. I wouldnt go looking for anything hotter. Shoot 50-100 rounds of 7.62x51 and see what happens.

Personally, Ive come to find that oil works better for most things than grease, especially for doing what your doing.
 

·
Registered
Joined
·
258 Posts
I just turned her over again and the amount of out of battery is EXACTLY what you get when the charging handle folds down.

Fold back up without pulling, and she is out of battery.

I push forward on the carrier in the ejection port slightly, and hear an audible clunk, and she seats.

something somewhere needs polishing.
That's not a polishing issue. If you are riding the charging handle like AK said, that will happen. If you are doing a full slap or release, then it should lock in the trunnion.

If it's not, that is an under powered recoil spring. That's the spring on the guide rod on the butt stock.

Too bad you aren't a little closer to Austin. HK delayed roller locking guns are my main stable item.
 

·
Banned
Joined
·
1,672 Posts
Discussion Starter #29
Its a thousand dollar rifle that is less than reliable. Two months to get it back from the factory, AFTER the election, or a couple of hours to drive to Austin and get this seen to. Easy choice for me. Pm me where your shop is and I can be there next tuesday. My day off.
 

·
Threepin'
Joined
·
4,012 Posts
Finally took my new PTR 91 to the range yesterday. Loaded a Mag with some Tula steel cased 150 grain FMJ, chambered, fired, ejected.

Sighted in again, squeezed, CLICK.

Manually chambered another round, on safe, retrieve the round, slight scratch on the primer.

Pulled on manually chambered round, fired and cycled.

Squeeze, CLICK.

ejected the round, this time small dimple in the primer.

Is this normal for a new PTR 91?

I know the manual says 250-300 rounds to break it in, but come on. If I spend a thousand dollars on a battle rifle it should at least go boom every time I pull the trigger.

On a funny note, my Century C308 eats the Tula like nobody's business, and it is built on a PTR receiver and barrel.

Is this normal break in for a new PTR? Anyone have one of these guns and can lend some guidance?
:(

Sounds like maybe the bolt isn’t cycling all the way forward after it gets sent to the rear. Might be underpowered ammo for the brand new recoil spring.

I recall mine having some break in issues with cycling and the spring a longgg time ago.

Try some hotter loads, and also clean the crap out of it.


Sent from my iPhone using Tapatalk
 

·
Banned
Joined
·
1,672 Posts
Discussion Starter #32
OK folks, cleaned, lubed with Super Lube PTFE grease and worked into all the bearing surfaces. She charges a LOT easier now.

Loaded three mags with Magtech first defense tactical M80 ball.
That's fifty rounds of brass case ammo.
after that (if it eats them all) the last mag of the Tula.

NOW lets see if I can get a tune out of this trombone..
 

·
Banned
Joined
·
1,672 Posts
Discussion Starter #33
My only excuse on all of this is unfamiliarity with the platform's idiosycrasies (sp?) if this is the fix.

Common sense should tell you machines work better with lubrication....
 

·
Comic, not your lawyer!
Joined
·
14,220 Posts
I'd also look at the magazine as a source of the problem; in my experience a lot of issues with semi-autos can first and easiest be ruled in/out as magazine related.

Get different mags, label them somehow, and try them and see if you can isolate issues to 1 magazine.

Barring that, the advice to deep clean it, and run the action a zillion times and polish, smooth, grease and lube it would be my other steps. It's a machine and that action needs to be worked and the easiest/cheapest thing is while your watching TV just sit and run that action for hours.
 

·
Banned
Joined
·
1,672 Posts
Discussion Starter #38
Well, the PTFE grease did the trick.

Oddly enough, there were two failures to fully chamber, out of 67 rounds. HELL of a lot better than the 50/50 ratio I was having. I will chalk them up to breaking in.

Note to self: when conducting "diagnostic" rapid fire with a .308 in an indoor range, (only one on the line at the time) knowing the lady manager is the only thing that keeps you from being tossed.

Doesn't help matters if the RSO leans in the door and says," Dammit ****** stop it!",

And you yell, "WOLVERINES!!"

Thank God they know me.
 

·
Comic, not your lawyer!
Joined
·
14,220 Posts
Well, the PTFE grease did the trick.

Oddly enough, there were two failures to fully chamber, out of 67 rounds. HELL of a lot better than the 50/50 ratio I was having. I will chalk them up to breaking in.

Note to self: when conducting "diagnostic" rapid fire with a .308 in an indoor range, (only one on the line at the time) knowing the lady manager is the only thing that keeps you from being tossed.

Doesn't help matters if the RSO leans in the door and says," Dammit ****** stop it!",

And you yell, "WOLVERINES!!"

Thank God they know me.
Glad the grease worked. I put grease on rails and bolts of a lot of my firearms to aid in cycling.
 

·
Golden Cockroach
Joined
·
498 Posts
I own a PTR 91. Back when I was actively going to a range and shooting, I had problems with my PTR 91 not cycling properly. It would shoot both steel case and brass case ammo just fine if it got chambered, but charging handle didn't always cycle the way it should when firing. In my case, I'm convinced it was an issue of temperature.

I store my PTR 91 in a Pelican case indoors (A/C - climate and humidity control). I was a member at an outdoor range shooting generally in the summer time (Texas summers - hot and humid). When I got to the range and unpacked the PTR and such, the gun was "cold". When shooting the gun "cold", I had problems with cycling. After I waited a while with the gun resting on the bench, for the metal to reach ambient temperature, I no longer had any cycling issues.

As you said in post #7, the bolt is TIGHT. I suspect the tolerances for metal expansion/contraction due to temperature aren't very generous.
 
21 - 40 of 49 Posts
Top