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Posted: 4/24/2008 6:59:28 AM EDT
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I put this up in the general technical forum and got some help. ar15.com/forums/topic.html?b=3&f=118&t=375096 Any additional help appreciated. First the gun.  Spikes Pistol Lower Denny's Flat Top Upper Denny's 11 1/2" VCQC Barrel RB Precision LPK Del-Ton Charging Handle & Bolt DPMS Chromed Bolt Carrier DPMS NM Front Site Del-Ton Upper Parts Yankee Hill Machine Phantom muzzle brake. (Oooo boy is this sucker gonna be loud....) Now the problem. Major problems with Failure to Eject. I started with two rounds of Wolf in the magazine for a function check as I just put this pistol together last Saturday. All went fine. Then three rounds. Worked fine. Then ten rounds and all was good. Then I switched to some of my 55gr reloads and problems started. I though, 'Must be my reloads since they are pretty 'mild'.' So I switched to some hotter 54gr reloads. Problems persisted. So I switched to some older Malaysian M193. Same problem. Then Federal Premium 69gr SMK factory loads. Same problem. Finally tried some Prvi 75gr Match. Same problem. See pictures. All pictures show fired cases that failed to eject. Apologies for pic quality, I only had a cell phone camera.     Finally the worst one. This one required removal of the buffer tube and some signifigant cussing to clear. Base of the round actually got pinched between the top of the bolt and the receiver. Using the charging handle made it worse as the bolt was back and pulling on handle 'wedged' the case even worse.   Additional information. I went back to just loading two rounds and had several where the bolt locked back on the last round but just left the case sitting on top of the magazine. Cycling seemed 'normal'. Every time it ran long enough to get to the last round in the magazine it would lock back on the empty magazine. Occassionally the round would remain in the chamber and the extractor just pulled over the rim. Tipping rifle up and empty would freely fall from the chamber. I have two thoughts on this. 1) Extractor upgrades needed. 2) Gas pressure is remaining too high?? Causing brass to 'stick' to the chamber walls a millisecond too long. I tried to think of every detail but if you need more information let me know. I tried all ammo types in my 20" rifle and all cycled fine. One last thing. I was out of Wolf and could not test it at the end to see if it worked as it had at the beginning. My pistol buffer kit showed up from PK Firearms and I'll get a picture of it later today. |
I am hoping it is that simple. I'll do a search, but will 'any' o-ring work? I have plenty to pick from by walking out to my garage. In fact I'll ask this question in another topic. |
I ran a couple of dry patches through the barrel but I am unsure why a brand new barrel would need a good cleaning. I also did not use Wolf for break in. I was doing a function check since I also built the lower. I was loading 2-3 rounds to make sure that it wasn't going to double on me. I am curious how you came to this conclusion since the Wolf was the only ammo that did function properly while M193, Federal and Prvi all failed? |
Cleaning the chamber even after a few rounds of Wolf is never a bad idea, for Wolf will usually leave behind a thin layer of crud that brass just seems to stick too. Plus the Dennys barrel is possible a little tight for better accuracy combined with a potental layer of crap and their you go. Do as the other said as I would, add an o-ring and better sping and brush your chamber. What do you have to lose 10 minutes of time. I'd be looking at the lip on the extractor real close too. Plus it never hurts to check the ejector also while your there just to be sure it too isn't hanging up a smidge. Good luck and have a safe weekend. |
These mods seem to be the consensus and I'll try to get the parts ordered tomorrow. They are so inexpensive relative to shipping I'll order 2-3 of each. It won't hurt to upgrade the other bolts I own at the same time. I need to visit the Build It Yourself forum. My bolts are the only parts of my guns I have never had disassembled. |
I just read my reply to you and it reads a bit 'snippy'. Not meant to.  I'll give the barrel a good cleaning, as you mention it'll only take a minute. Denny runs a Wylde chamber if I remember correctly so it shouldn't be 'tight' but anything is possible. I'll call Denny on Monday to check for sure. Honestly I would be amazed if there was any buildup from the Wolf (recent production, polymer coated) ammo. I shot less then a box of it out of cold gun. I was thinking that maybe the steel case had more 'grip' on the rim, either from the steel or the polymer coating. While the brass cases would be 'slicker'. Whatever solves it, I am glad I built the pistol so I could get all of this troubleshooting out of the way while waiting for the Form 1. |
I use this setup in my rifles also.... |
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Woo Hoo! O-ring to the rescue. I have been traveling a lot and busy getting our house sold so instead of ordering any parts I dug into my o-ring assortment and found one that was close to what I saw pictured in the various upgrade kits. Not quite as thick but it worked like a champ. I fired about 50 rounds this afternoon, all offhand. All were some 'lower power' reloads w/ 50gr Speer TNT's in WCC brass cases. Instead of ending up in the ejection port they all landed in nice groupings about 10' to my right at about 3 o-clock. Not one failure to eject or feed. Thanks for the help! |
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