legion85 Posted April 25, 2015 Share Posted April 25, 2015 (edited) Hello all, looking for some help with a brand new JP rifle my brother bought that is not cycling. He took it to the range and was completing the break in process as instructed by JP which consisted of: Shoot 5 shots Swab with solvent Swab JP Bore Compound Swab with solvent Shoot 15 rounds Swab with Solvent Swab JP Bore Compound Swab with solvent *begins to fail cycling here* Shoot 15 rounds, charging every single round Swab with Solvent Swab JP Bore Compound Swab with solvent At this point, he had not touched the gas block at all. We have tried turning the gas block all the way out, and the bolt barely moves. It does not eject the round. I watched the bolt on one shot, and it moved maybe half an inch. My guess is that there is an obstruction at the gas block or in the gas tube. Any thoughts? I would like to avoid removing the hand guard and gas block. We are both pretty disappointed in the JP. Will be shooting them an email and phonecall on Monday. Thanks ahead of time for any input. Edited April 25, 2015 by legion85 Link to comment Share on other sites More sharing options...
TonytheTiger Posted April 25, 2015 Share Posted April 25, 2015 Interesting. My brother had similar but less severe short stroking issues on his new 6.5 Grendel JP. First 20 ran fine, somewhere between 20 and 60 rounds we had opened the GB all the way and still had probably 50% failure rates. We decided to take it in out of the snow, clean the factory lube out of it, de-burr any rough edges in the mag and re oil with Mobil 1. Next day it ran perfect and we turned the gas down a little and it's been fine for all 200 rounds since. But even when it malfunctioned the bolt traveled more than half an inch, that sounds like a serious issue. His has the JP branded Syrac adjustable GB for what it's worth, I've heard some bad things about them. Link to comment Share on other sites More sharing options...
legion85 Posted April 26, 2015 Author Share Posted April 26, 2015 Thanks for your input Tony. This has the JP gasblock. Link to comment Share on other sites More sharing options...
RiggerJJ Posted April 26, 2015 Share Posted April 26, 2015 my guess is JB is clogging the gas tube or block...use it sparingly! jj Link to comment Share on other sites More sharing options...
Bigsampson Posted April 26, 2015 Share Posted April 26, 2015 I sent an email to JP several weeks ago on a similar issue and have gotten nothing back. I bought one of their barrel, gas block, comp kits to install in a custom build. Installed the whole thing and took it to the range. No matter what I did, could not get the gun to run. Took it home to see if the gas block was not aligned correctly. Was perfect. Decided to swap out the gas block thinking there may have been an internal problem. Trying to push out the retaining pin was impossible. Would not budge. So, I had to drill it out. When I did that, I found the problem. Either the barrel with gas block and tube was dropped or "something" The tube, after being pinned was shoved so hard up into the gas block that the pins sheared off and moved the gas tube up into the block so the holes didn't line up. The reason i could not push the pin out was that only the ends were left in the block. Not saying that is what is going on with yours, but ..... Top pic is an old tube showing the correct holes with the messed up tube. Both pics show where the sheared off pins are still in the tube. Link to comment Share on other sites More sharing options...
Hi-Power Jack Posted April 26, 2015 Share Posted April 26, 2015 I sent an email to JP several weeks ago and have gotten nothing back. That is disturbing. Link to comment Share on other sites More sharing options...
Bigsampson Posted April 26, 2015 Share Posted April 26, 2015 I suspect the OP's gas block is simply out of alignment. Link to comment Share on other sites More sharing options...
legion85 Posted April 26, 2015 Author Share Posted April 26, 2015 Bigsampson, that looks terrible. Can't believe you haven't heard back yet. Since it worked for a couple shots, I think that I'm working with an obstruction. Going to have to figure out how to take off the handguard and gasblock to see if there's debris or the bore compound causing a blockage. If the gas block isn't lined up correctly, that would be really disappointing for a new rifle that cost over 2k. Link to comment Share on other sites More sharing options...
co-exprs Posted April 26, 2015 Share Posted April 26, 2015 I wonder if that gas tube was oit of alignment with the BCG and got shoved forward by the BCG going into battery. Link to comment Share on other sites More sharing options...
GPRifle Posted April 26, 2015 Share Posted April 26, 2015 It is not really rocket science. Somewhere from the gas port to the bolt, gas is leaking or there is something blockning the way. I am guessing the 2nd of the two. Take it apart and have a look. Link to comment Share on other sites More sharing options...
HRider Posted April 26, 2015 Share Posted April 26, 2015 I wonder if that gas tube was oit of alignment with the BCG and got shoved forward by the BCG going into battery. I was wondering the same thing. Try calling JP during business hours, I have talked to them like that before. I have not had to call them about my CTR-02, but have called them about doing work to other rifles. Hurley Link to comment Share on other sites More sharing options...
Bigsampson Posted April 27, 2015 Share Posted April 27, 2015 "I wonder if that gas tube was oit of alignment with the BCG and got shoved forward by the BCG going into battery." With enough force to shear that pin? I don't think that is reasonable. Besides, upon installation, the bolt functioned normally with no binding. It would have taken quite a smack to shear those pins and drive the tube back. Link to comment Share on other sites More sharing options...
co-exprs Posted April 27, 2015 Share Posted April 27, 2015 There is far more force applied by the BCG slamming home, than by a drop on the floor. Link to comment Share on other sites More sharing options...
RoanWrangler Posted April 27, 2015 Share Posted April 27, 2015 I had a similar issue last year. After firing a few rounds, the bolt stopped cycling. The gas block adjustment screw is set with Loctite (or similar product) at the factory making it difficult to adjust the first time. JP responded quickly with several suggestions. Tried all of them and eventually was instructed to return the rifle. A couple of weeks after the rifle was returned, a tech analyst called and I was informed that the gas tube had ruptured and that they needed to rebuild the upper. The rebuild took a couple more weeks. Since being returned, the rifle is a dream. Link to comment Share on other sites More sharing options...
Chuck Anderson Posted April 27, 2015 Share Posted April 27, 2015 Did you check the carrier key is still tight to the top of the BCG? Every now and then the screws don't get staked and work their way loose. Link to comment Share on other sites More sharing options...
legion85 Posted April 28, 2015 Author Share Posted April 28, 2015 (edited) I took the gas tube off and I was able to blow air through it I also blew air through the barrel and with the bolt in the gun, and air was going through the gas block fine as well. The gas block cannot be misaligned because of the way they installed it: with a rollpin through the gasblock and a slot in the barrel...also the rifle shot fine for the first 20 or so rounds, so I doubt it is misaligned. Gas key is fine...nothing wrong there. I didn't find an obstruction in the gas block or gas tube. The gas block is lined up correctly. I don't know what else it could be. The bolt moves back and fourth very smoothly...no difference in resistance than that in my Stag 3G. One thing I tested at the end though was air flow through my Stag 3G vs airflow through the JP gas sytem. The Stag had noticeably more air flow....but it is a wide open gas block. I opened up the adjustable gas block to wide open and the air flow was still less...but how much is up to my perception and it didn't seem like a big deal. I can't take the gas block completely off because of the way the compensator is installed....I will probably try shooting it one more time before it gets shipped back to JP. On another note...the upper and lower receiver play on the JP is very noticeable. It is more than on my Stag. I was planning on getting a JP but I don't think I will be anymore. Very disappointed. I'll let you know how customer support is...so far they respond to emails about once a day. Edited April 28, 2015 by legion85 Link to comment Share on other sites More sharing options...
3GunRunner Posted April 29, 2015 Share Posted April 29, 2015 If you dont get a response when an Email is sent to them often times the address is incorrect. Try one of the guys direct Email addresses. BEN@JPRIFLES.COM or DUSTIN.HELTEN@JPRIFLES.COM You could try calling but their phone lines have been pretty busy as of late. 651-426-9196 x103 for Ben or x107 for Dustin. It is also prety rare that JP has a receiver set that doesnt fit well. I know if you want it to be rock solid you should get one of their Billet receiver sets and it will be totally solid with no movement. Link to comment Share on other sites More sharing options...
Bigsampson Posted April 30, 2015 Share Posted April 30, 2015 Had a long conversation w JP today. Emails got mixed up when they responded to my initial contact. While there is no telling what caused the defect, JP was as much surprised as to the issue as was I. They agreed that there was no way that a bolt could possibly slam forward with enough force to shear the gas block pin. Had to be a major smack on the end of the gas tube to make this happen. There had to be another cause. No witness marks on the shipping box or gas tube hide the root cause as well. When shipped, the gas blocks are not typically tight, so the entire tube and block assembly could/should have slid. At any rate, the conversation was constructive. I really don't want anything out of the deal. I have gas tubes and blocks, my concern was from a QC or QA perspective. over then next few weeks, I'll send them the tube and block so they can analyze . Hopefully, they can learn from the issue and prevent a recurrence. The fact that they are watching these boards and responding to emails is enough for me. Link to comment Share on other sites More sharing options...
legion85 Posted April 30, 2015 Author Share Posted April 30, 2015 FIXED!!!!! I called JP today and spoke with Dustin. I walked him through everything that I had done, and we just talked about everything it could have been. He brought up one thing that I had not considered at all (due to my lack of knowledge of what the gas does once it hits the gas key)....to check the gas key for a blockage. I checked the gas key to see if it was loose...but never considered if it was blocked. I got home and looked into the gas key and saw something in there...I couldn't tell what. I blew some air into it...and it was definitely blocked. I then filled the gas key with CLP, and stuck in a q tip. When I pulled the qtip out...the suction pulled out something that blew my mind: a PRIMER. What are the chances of that? When I think about the time it takes for the bolt to open and close during a shot....and for a primer to come out of a casing and go into the gas key....that must be less than one in a million odds. I'm assuming the rifle will function perfectly now...I'll let everyone know once I make it out to a range. Takeaways: Wasn't JP's fault. JP's Support was AWESOME. This was a crazy freak occurence. Will probably install an accuwedge and be a very happy camper. Link to comment Share on other sites More sharing options...
legion85 Posted April 30, 2015 Author Share Posted April 30, 2015 For those who like pictures....I wouldn't have believed it unless I pulled it out myself. Link to comment Share on other sites More sharing options...
striped1 Posted April 30, 2015 Share Posted April 30, 2015 accu-wedge is a great way to turn it back into a single shot. superfluous at best to the ar platform and in my experience and opinion, harmful to it. Link to comment Share on other sites More sharing options...
Shooter115 Posted April 30, 2015 Share Posted April 30, 2015 Wow! What are the odds? Never seen nor heard of that one before. Link to comment Share on other sites More sharing options...
Steve RA Posted May 1, 2015 Share Posted May 1, 2015 Some time back there was/is a post here about someone else that had that misfortune. Still a very rare occurrence. Glad you found it. Link to comment Share on other sites More sharing options...
BitchinCamaro Posted May 3, 2015 Share Posted May 3, 2015 (edited) Googled it. Now that I know it can happen, I bet that it's gonna happen to me . http://jerkingthetrigger.com/2012/09/10/complex-ar-15-malfunction/ Edited May 3, 2015 by BitchinCamaro Link to comment Share on other sites More sharing options...
dbletap_ed Posted May 5, 2015 Share Posted May 5, 2015 Glad to hear it worked out and you are happy with JP. I recently received my 3 year old JP15 back after sending it to them with some issues and I am completely blown away by the quality of their service. Link to comment Share on other sites More sharing options...
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