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Posted: 9/16/2013 9:55:15 AM EDT
Run a sear?  Mag dumps?  Any issues?

I know that alot of the PTR parts are good to go but I was wondering how the barrel and trunnion on the newer ones compair to the original FMP parts?  Will they last as long?  I am trying to decide if I should pony up for an EBO or FMP or just pick up a PTR91GI.

Thanks!
Link Posted: 9/16/2013 11:38:49 AM EDT
Same here.  I'm on the fence between the PTR and a HK.  Does PTR have the disappearing bolt-gap issue resolved?  

Link Posted: 9/16/2013 11:46:58 AM EDT
I have a GI and I have run every type of ammo through it and never had any issues.... round count prob in the 2500 area.

Link Posted: 9/16/2013 12:41:05 PM EDT
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Originally Posted By bbohman:
I have a GI and I have run every type of ammo through it and never had any issues.... round count prob in the 2500 area.

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How is your bolt gap?
Link Posted: 9/16/2013 12:42:59 PM EDT
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Originally Posted By Dissident:
Same here.  I'm on the fence between the PTR and a HK.  Does PTR have the disappearing bolt-gap issue resolved?  

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PTR has not had a bolt gap issue that I am aware of.  JLD did have a run of a few hundred guns that had a soft trunnions, due to welding issues I think.  Century has had issues.

Link Posted: 9/16/2013 2:55:23 PM EDT
[Last Edit: 1/29/2014 4:32:26 AM EDT by har1340]
I've run some 2000 rounds thru my PTR91 in both semi and full. I love my PTR. I also have an original HK.22lr conversion kit that works 100% when clean.

Go get one!
Link Posted: 9/17/2013 6:29:01 AM EDT
Plenty people on HKpro have used a sear with the PTR32s
Link Posted: 9/18/2013 9:58:42 PM EDT
bolt gap bolt gap

gap bolt

for the life of me, I've never heard it before and never encountered it with the CAI Cetmes, c93's, FMP's, 91, SAR8 SAR3...

Nothing until now suddenly everyone is an HK expert out of the blue after they mention....oh oh oh oh BOLT GAP.

The PTR and the GI edition. I used it on a xproduct 50rd and a fleming sear and it ran fine......like a raped ape....

Used the blue ammo and the rollerless bolt..

boringly reliable.....

Link Posted: 9/19/2013 1:22:27 PM EDT
very reliable.. very accurate.... thousands of rounds, and no issues.
Link Posted: 10/1/2013 6:45:36 AM EDT
"Bolt gap" is important.  It should be measured regularly, regardless of make of gun.  Ignore it at your own peril.

k
Link Posted: 10/1/2013 5:17:10 PM EDT
Link Posted: 10/1/2013 5:18:25 PM EDT
Link Posted: 10/1/2013 6:20:37 PM EDT
I love doing mag dumps out of my gi never had a single problem.
Link Posted: 10/2/2013 4:28:50 PM EDT
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I need this rifle. Make my wife understand.
Link Posted: 10/14/2013 9:16:41 AM EDT
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Originally Posted By Jozsi:


boringly reliable.....

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Best way I've ever heard someone explain it.  LMAO.


OP you can pay the worry-free tax and get the real deal....or you can drop less $$ on the GI and spend the difference in ammo.  That's what I did and I've never looked back.  Love my GI.
Link Posted: 10/14/2013 9:32:34 AM EDT
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Originally Posted By xciapup:
"Bolt gap" is important.  It should be measured regularly, regardless of make of gun.  Ignore it at your own peril.

k
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That was the point. Is this issue a over exaggerated, over hyped internet lore issue, or is it a real issue?

I am sure most of you will disagree using info you heard on the internet.
Link Posted: 10/15/2013 6:37:04 AM EDT
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Originally Posted By MOLOT:


That was the point. Is this issue a over exaggerated, over hyped internet lore issue, or is it a real issue?

I am sure most of you will disagree using info you heard on the internet.
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Originally Posted By MOLOT:
Originally Posted By xciapup:
"Bolt gap" is important.  It should be measured regularly, regardless of make of gun.  Ignore it at your own peril.

k


That was the point. Is this issue a over exaggerated, over hyped internet lore issue, or is it a real issue?

I am sure most of you will disagree using info you heard on the internet.


I'd only be concerned if I bought a Century Cetme, G3, or C93 build.  HK or PTR should be fine for factory new.  I think it's way overhyped because of some C93s that came with ground bolts to make them "work" mixed with bad garage builder MP5 clones.  The HK action isn't as easy to put together as an AK or AR.

I've had my PTR for almost 10 years, and I only bought some feeler gauges earlier this year to check it since I'm going to be changing out the locking piece to run suppressed.

For roller locks, it's an easy something to check if it doesn't work right.  Other than that, checking it every month and charting the change would be ridiculous.  Just eyeball it, you'll be able to visually tell "too far" and "no gap at all" before it becomes a problem.
Link Posted: 10/15/2013 12:59:45 PM EDT
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Originally Posted By Findsman:


I'd only be concerned if I bought a Century Cetme, G3, or C93 build.  HK or PTR should be fine for factory new.  I think it's way overhyped because of some C93s that came with ground bolts to make them "work" mixed with bad garage builder MP5 clones.  The HK action isn't as easy to put together as an AK or AR.

I've had my PTR for almost 10 years, and I only bought some feeler gauges earlier this year to check it since I'm going to be changing out the locking piece to run suppressed.

For roller locks, it's an easy something to check if it doesn't work right.  Other than that, checking it every month and charting the change would be ridiculous.  Just eyeball it, you'll be able to visually tell "too far" and "no gap at all" before it becomes a problem.
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Originally Posted By Findsman:
Originally Posted By MOLOT:
Originally Posted By xciapup:
"Bolt gap" is important.  It should be measured regularly, regardless of make of gun.  Ignore it at your own peril.

k


That was the point. Is this issue a over exaggerated, over hyped internet lore issue, or is it a real issue?

I am sure most of you will disagree using info you heard on the internet.


I'd only be concerned if I bought a Century Cetme, G3, or C93 build.  HK or PTR should be fine for factory new.  I think it's way overhyped because of some C93s that came with ground bolts to make them "work" mixed with bad garage builder MP5 clones.  The HK action isn't as easy to put together as an AK or AR.

I've had my PTR for almost 10 years, and I only bought some feeler gauges earlier this year to check it since I'm going to be changing out the locking piece to run suppressed.

For roller locks, it's an easy something to check if it doesn't work right.  Other than that, checking it every month and charting the change would be ridiculous.  Just eyeball it, you'll be able to visually tell "too far" and "no gap at all" before it becomes a problem.



Waiting on a suppressor now for the FAL, was considering it on the PTR (SC) what has to change about the locking piece?
Link Posted: 10/16/2013 11:09:58 AM EDT
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Originally Posted By maxpower762:

Waiting on a suppressor now for the FAL, was considering it on the PTR (SC) what has to change about the locking piece?
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Has to do with the back pressure the suppressor will add to the system.  The default locking piece is designed to operate with an unsuppressed weapon, so the additional pressure from the suppressor will cause more force on the bolt head, unlocking the weapon too soon.  It'll batter the action and beat it up pretty good, and you'll feel additional recoil.  If you were going to do it occasionally, I wouldn't worry too much about it.  In my experience, once I am able to suppress a rifle, I tend to shoot it that way all the time.

The #17 (36 degree) LP is what I'll be going to.  That's the one intended for the HK21E and typically recommended for HK91/PTR91 suppressed use.  It'll hold the action closed a hair longer and avoid beating the system up.  Changing out the LP will affect bolt gap though, and this is the scenario where I'd recommend checking it.  If it remains in-spec, yay; if not, I'll probably get a new bolt head and rollers to bring it into spec so I can switch back and forth as needed.

Hope that helps somewhat!
Link Posted: 10/21/2013 9:49:54 AM EDT
Only rifle I had any bolt gap issue with was a Century imported Portugese FMP gun. I swapped out the rollers and that was about 1500 rounds ago. No problem.
Link Posted: 10/21/2013 8:22:53 PM EDT
Bolt gap is an indication of roller and trunnion geometry. Too small of a gap means the rollers are too far into the trunnion recesses. As a result the action unlocks easily/early and sends the bolt/carrier rearward at a higher velocity. In extreme cases, when the carrier hits the buffer the bolt will hammer back against the locking piece, pushing the rollers outward.

This will put dimples in the reciever channels and risks cracking parts you don't want cracks in.

It seems the guys at HK are a little smarter about this issue than at least one Arfcommer, just maybe.
Link Posted: 11/14/2013 5:43:26 AM EDT
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Originally Posted By Ronnie_B:
Bolt gap is an indication of roller and trunnion geometry. Too small of a gap means the rollers are too far into the trunnion recesses. As a result the action unlocks easily/early and sends the bolt/carrier rearward at a higher velocity. In extreme cases, when the carrier hits the buffer the bolt will hammer back against the locking piece, pushing the rollers outward.

This will put dimples in the reciever channels and risks cracking parts you don't want cracks in.

It seems the guys at HK are a little smarter about this issue than at least one Arfcommer, just maybe.
View Quote


Indeed ! Bolt Gap is very important and should be checked regularly. It's not some internet commando made up shit. If you're going to own these types of firearms I suggest you educate yourself about them thoroughly so you don't sound like an ignoramus saying bolt gap doesn't mean anything.
Link Posted: 11/20/2013 5:36:03 PM EDT
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Will that version allow for a carry handle to be installed?
Link Posted: 11/21/2013 5:19:25 AM EDT
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Originally Posted By CitizenSoldier556:


Indeed ! Bolt Gap is very important and should be checked regularly. It's not some internet commando made up shit. If you're going to own these types of firearms I suggest you educate yourself about them thoroughly so you don't sound like an ignoramus saying bolt gap doesn't mean anything.
View Quote View All Quotes
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Originally Posted By CitizenSoldier556:
Originally Posted By Ronnie_B:
Bolt gap is an indication of roller and trunnion geometry. Too small of a gap means the rollers are too far into the trunnion recesses. As a result the action unlocks easily/early and sends the bolt/carrier rearward at a higher velocity. In extreme cases, when the carrier hits the buffer the bolt will hammer back against the locking piece, pushing the rollers outward.

This will put dimples in the reciever channels and risks cracking parts you don't want cracks in.

It seems the guys at HK are a little smarter about this issue than at least one Arfcommer, just maybe.


Indeed ! Bolt Gap is very important and should be checked regularly. It's not some internet commando made up shit. If you're going to own these types of firearms I suggest you educate yourself about them thoroughly so you don't sound like an ignoramus saying bolt gap doesn't mean anything.


Granted it's been a few years, but this was a topic in the HK MP5 armorer's course I took with none other than Bob Schultz back in 2007. "Bolt Gap" is a checkup/maintenance thing, just like replacing gas rings or extractors on an AR. It's not hard to check on, you just need some feeler gauges and some knowledge on the roller sizes and their effect on the gap. The platform is pretty much the same across the board for the roller locked rifles, obviously there are changes in the dimensions and needed specs but the relationships are the same.

Put simply, if you measure the gap and the dimension is at/smaller than the minimum, you would install a + sized set of rollers. I don't remember what the size differences were or how much it affected the gap by memory, but it was straightforward. If the gap is too big, install a smaller roller.

You can look at HK Parts, if you ever wondered why there were different sized rollers and why people would even buy them, there you go. Better yet, snag a G3 Armorer's manual, they're straightforward and worth it.
http://www.hkparts.net/shop/pc/HK-91-HK-G3-Bolt-Group-c113.htm?pageStyle=h&ProdSort=19&page=2&idCategory=113
Link Posted: 11/21/2013 12:17:50 PM EDT
[Last Edit: 11/21/2013 12:21:27 PM EDT by akuser-47]
This comes up often and does need to be kept in check. CIA had issues with some of their cetmes and gap. I had found many at the lima gun show years back the gap was terrible. Not safe the guys selling them said ol it is in spec. Lol Know your rifles limits or be destroyed by your own faults. If you ever see shell casings with ruptures or expansion than you need to look into this! For your own sake.
Link Posted: 1/28/2014 2:57:22 PM EDT
Just placed order for PTR91 A3S through Atlantic Firearms...asked about any discounts for being member here or host of other firearms sites...one ought to be worth a penny and 5 ought to be worth a couple bucks :)   Now to decide whether to get aftermarket or tactical forgrip for use of 1913 styled bipod adapter or get HK bipod...
Link Posted: 1/28/2014 6:51:25 PM EDT
Excellent choice. I added the PTR aluminum hand guard, cheek riser and bipod to mine. Just mount the optic of your choice and you are GTG.







 
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