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Discussion Starter #1

So, JLD PTR s/n# A203X, Very accurate, MOA at 100M. Now for the problem. This weapon delivers (guess) 30% more recoil than my other JLD PTR. Of greater concern is the bolt gap is nominal .006/.157 and the darn charging operation is VERY DIFFICULT to cycle. ONCE the charging handle is hammered open, it will cycle fine. But slap it closed and it is a rubber hammer occasion to move it. Everything else seems to be running fine. I have not found any references to this issue on the forum, so I am concerned this is a "rare" occurance and not many know a fix. What say you guys with mounds of empties behind you.

On a second note, does anyone have success with reloading brass that has been 'errupted' from a PTR. I have seen train wrecks with less damage. But this thing sure will put the 'ole bean in the X ring!! And that is all that matters.
RollTide (and Aggies)
 

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Increase your bolt gap. Check the buffer, make sure it's there and works properly. How are you able to determine that the recoil is exactly 30% more than your other gun? Are you using the same type stock on both rifles?
 

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On reloading:
Look into a port buffer to keep the dings down and/or take a old t-shirt and lay it across the top of the rifle and it will act like a punters practice net. The cases will slow down and not get beat up and drop next to the gun on the bench. Learned this trick from an AR guy shooting 300 Blackouts.

More on reloading:
Maybe look into a small base die if you have any chambering issues and test the brass before you reload it after sizing. Dents will get blown out on the next round of firing. Just make a real good check for cracks in cases, you are stressing the brass more.
 

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Discussion Starter #4
HKshooter, , How do I increase bolt gap?? New to PTR's just learning. 30% is an estimate. Have fired MANY weapons of many variations and loadings. Just a guess. Also, firing the PTR's sideXside. And firing a Weatherby .300 Mag. The hard hitting PTR was simular to the .300. Not a problem in single shot pure target situations, but could be a concern in a tactical situation. Follow up could be compromised. Have a new heavy buffer on the way.

Eldos1, port buffer on the way also. Hope that will tame the beast. Will watch the cases very closely. They are NEW so will be once fired when reloaded. Will keep an eye on them. Also, will retire them several cycles early as a safety precaution. Hopefully, the port buffer will offer enough protection to mitigate furter major denting of the cases.

Thanks to you gents for your input. Much appreciated.
RollTide
 

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Top right of the page. Type in "bolt gap", grab a cup of joe or a brew, read until your eyes cross. There's not another place on the net that covers bolt gap like this place.
These roller delayed guns live and die on proper bolt gap. On correctly built rifles gap is not hard to change or maintain but set incorrectly can ruin a rifle in short order. Excessive recoil is often a symtom of incorrect bolt gap. Though your gap is technically in spec, it's at the last cat whisker of spec. I suspect that once you get the gap into the middle of the range you'll notice a considerable difference in recoil. What's the gap on your other rifle?
 

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Discussion Starter #6
.012 and it is just a dream to handle and fire.

I will read and study bolt gap. May need a bit more guidance, but I will git r done!! Thanks Much
 

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Discussion Starter #7
Well I read everything and I am either a slow learner or missed something. I can see that I have a soft trunion or roller issues or bolt issues. What I need to know is what to do about it?? Do I send it somewhere and where do I send. Or do I purchase parts and replace?? HELP?? Remember I am a Newbie. Fairly good mechanic with some tools. No milling or CNC's.

It is well obvious HKshooter diagnosed the problem/s. How to resolve is now the question.
Thanks Guys
 

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The abridged version:
- Clean the gun including taking apart the bolt and cleaning the chamber face and trunion.
- Check bolt gap in clean gun, only the lightest of resistance should be felt on the feeler gauge.
- Make sure hammer is forward (check gun is unloaded ;-)
- Repeat bolt gap measurements a couple times and record.
- Compare to specifications
- See G3 Armors Service Manual: http://www.ar15.com/content/manuals/G3_Armorer_Manual.pdf
- Take the bolt group apart and check the size roller installed (may have to remove roller retainer roll pin and plate).
- Purchase new over size rollers, retainer plate and roll pin (they get lost).
- Optionally purchase new locking piece (low cost but probably not the issue).
- Reinstall and check bolt gap again.
- If needed sent to HK Smith if this does not correct and/or something moves too much / changes too much with use.

HK Notes and Accessories

 

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Send it to Ghillie if the + rollers don't fix it
 

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Oh and if you don't have one, install a case buffer.. saves a lot of wear and tear on the brass.. I reload mine 5 x out of fluted chambers before I sideline it
 

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Some things you can do yourself, study the trunnion from the front, look for a crack. PTR had some issues with that. If you find no crack you could replace the rollers, a very simple and inexpensive job. To determine the size mic the ones in the bolt head to determine the number then get the next set two sizes bigger. Check bolt gap and test fire.
If you find a crack the job is beyond most of us to repair so rely on the pros. Note that the best I know, PTR made their warranty retroactive so your serial number may well be covered. Sending it to PTR for an eval and repair could be an option. Next, this guy made a very good recomendation.

Send it to Ghillie if the + rollers don't fix it
Jeff (Ghilliebear) is a board regular, a vet, an excellent HK smith, and one hell of a nice guy. He'd do you right for sure. I'm willing to bet that if your trunnion isn't cracked, rollers will make your rifle and you happy.
 

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hkshooterusp checking for the crack is a good idea, one of these days will have to see if any of our home ranges overlap (assuming we already don't shoot together w/o knowing it .... ;-)
A few photos and threads on cracked trunnions, one of the reasons to run either a factory gun or a custom built by one of the current crop of HK smiths

http://www.hkpro.com/forum/hk-clone-talk/140364-ptr-91-gi-quality-thread-2-check-your-trunions.html


http://www.hkpro.com/forum/hk-clone-talk/141081-ptr-qc-issues-new-gi-model-cracked-trunion.html


http://www.hkpro.com/forum/hk-clone-talk/141797-suspect-trunnion.html


http://www.hkpro.com/forum/hk-clone-talk/143469-ptr-trunnion-issues-detailed.html
 

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It must be said however that most PTRs do not have this nasty little issue. Mine does not, near 1,000 rds so far, no loss of bolt gap, still at .015, no cracks or other issues
 

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Do you have the original stock on it? I will put money on you NOT having a recoil buffer. My JLD PTR (210#) had a steel plate and NO recoil buffer.
 
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