phantom01231 Posted April 22, 2013 Report Share Posted April 22, 2013 Ok bare with me this might be a little long. I built my rifle about a year ago and have not had any issues with it untill recently. My rifle will shoot just fine with any factory ammo I can get my hands on. I've shot cheap 147gr junk to 168gr my wallet is now empty ammo and no issues. Ok so I recently started reloading. I worked up a load using some xbr8208, cci primers, 165gr Hornady sst, and ppu brass. The first time I took the ammo out to the range it worked just fine with no issues. With the hottest load I worked up the fps was still a little low so on the next batch I increased the charge just a little. (All of this was done over a chrono.) Now the second time I took it out with this ammo I started getting cycling issues. Mostly failure to eject. When the cases would eject a new round would not get loaded. I thought the issue with the ammo Was the crimp so I put a better crimp on the ammo and still nothing no change so I'm at a loss. Keep in mind that the rifle still works fine with factory ammo. Now yesterday I was at the range and I had the ammo and I let another guy with a carbine 308 ar try the ammo and his shot it just fine with no issues and mine still wouldn't. Any ideas! I'm thinking buffer and spring but I'm not sure. I'm using a 308 buffer and spring and tube from Fulton. Quote Link to comment Share on other sites More sharing options...
bubbasks Posted April 22, 2013 Report Share Posted April 22, 2013 Have you checked if that load is sticking in your chamber? My be sticking and slowing down your cycle enough to not kick back enough to feed a new round. Try feeding single rounds and see if the bolt locks. What kind of loads and speeds are you getting? Quote Link to comment Share on other sites More sharing options...
phantom01231 Posted April 22, 2013 Author Report Share Posted April 22, 2013 I was droping about 42.8 gr of powder I think and pushing around 2680 to 2690 fps. I dont have my charts in front of me right now but thats about ball park. Thats when the rifle would cycle with that round. I upped the powder to 43 and thats when it went to crap. As far as I can tell the rounds are not sticking and the bolt will lock injust fine. That im sure of. Everything is the same but the ammount of powder. As fas as what im pushing with the 43 gr of powder im not sure I havent had a chance to put it over the chronograph. Im thinking its overgassing but im just not sure. Quote Link to comment Share on other sites More sharing options...
98Z5V Posted April 22, 2013 Report Share Posted April 22, 2013 Carrier speed - cycling too fast. Extractor can't yank the old round out due to the speed, and the carrier is going so fast that it's over-running the next round in the mag, and not picking it up. Quote Link to comment Share on other sites More sharing options...
racerken70 Posted April 22, 2013 Report Share Posted April 22, 2013 (edited) it sounds like the first batch with new brass worked good and after that you started to have problems, are you using small base dies to size your brass? gas guns are a little pickier about brass size than a bolt gun is. I don't think going from 42.8 to 43 is going to make a major difference Edited April 22, 2013 by racerken70 Quote Link to comment Share on other sites More sharing options...
phantom01231 Posted April 22, 2013 Author Report Share Posted April 22, 2013 The brass was not new by any means. And im using full length dies. I would think that much powder would make a difference ethier but the cases was almost full with powder so!! I think thats what I was dropping im not sure like I said ill have to pull my notes out. Oh and 42ish to 43 ish is like max load in most books ive seen for my round Quote Link to comment Share on other sites More sharing options...
Tripledeuce Posted April 22, 2013 Report Share Posted April 22, 2013 The chamber on my DPMS 260 Rem. was "withen Specs", but a match grade chamber removed several thousandths from the body of the chamber. Reamer was dropped into the chamber, and turned by hand. Full length sizing is NOT the same as using a small base sizer die. I would reccomed a chamber cast, and carefull miking of it and the fired brass. Respectfully Terry Quote Link to comment Share on other sites More sharing options...
98Z5V Posted April 23, 2013 Report Share Posted April 23, 2013 phantom, you're running almost 2,700 fps with a 165gr projectile - you've got them flying fast as hell. You're at the upper limits on the powder charge. Going up that 0.2 grains is enough to put you over the edge, in this case... You do have a high amount of gas pressure, at that combo. Quote Link to comment Share on other sites More sharing options...
phantom01231 Posted April 23, 2013 Author Report Share Posted April 23, 2013 Im gonna dial the powder charge back down and see what happens. Ill keep you guys posted. Tripledeuce, I'm fully aware that a small base die and full length is diffrent. I use a case check guage on every round and haven't had one fail yet after resizing. not all dies are created equal. My full length seems to size just right where it needs to be. I do plan on picking one up however (small base) as I have another 308 in process and well not all chambers are created equal. But I will keep that in mind though about that being a potential issue. If it was though wouldn't I be seeing an issue with the round chambering vs failing to eject. Quote Link to comment Share on other sites More sharing options...
survivalshop Posted April 23, 2013 Report Share Posted April 23, 2013 What does the primer look like on spent case ? Any signs of over pressure ? Heavy crimp can cause case shoulder set back & even though you checked case after sizing , how about a loaded round ? If rifle functions with factory , ya know its the reloading procedure, of course. Just go back & go over what you are doing & it will come to you . What kind of crimping are you using ? Quote Link to comment Share on other sites More sharing options...
phantom01231 Posted April 23, 2013 Author Report Share Posted April 23, 2013 Other than some cases getting bashed from the FTE everything looks kosher. Yeah I know its not the rifle at "fault". Like I said im gonna dial the powder back down and see what happens. Quote Link to comment Share on other sites More sharing options...
phantom01231 Posted April 24, 2013 Author Report Share Posted April 24, 2013 Update: well I started cleaning up the brass for the rounds I just shot and had issues with. None of the case heads were torn but the did get roughed up enough that the would not fit into the shell holder easy. Also found marks from the extractor pin on the heads. Not so much dents but good enough you can tell it was there. Also it seems as if the case walls may have been over stressed as they were extremely hard to run into die. The factory ammo I shot looks brand new and resized like a champ. Quote Link to comment Share on other sites More sharing options...
phantom01231 Posted April 29, 2013 Author Report Share Posted April 29, 2013 Update: Ok so I went back out to the range yesterday after making some new hand loads. I dropped the charge in the rounds from 43 to 42 grains. World of difference. 90 percent of the issues are gone. I still had a few jams and some failure to lock open after the last round. Out of 60 rounds this only happened a few times. After cleaning her all up and inspecting her those issues seem to be mag related. One of my mags has a really soft spring. So I got some new mags coming that should take care of that. Bolt and related parts all check to be in good working order. The ejector looks like it has taken a slight beating from the whole ordeal so im going to order a new one with a spring to be safe to it appears everything is all good now. Quote Link to comment Share on other sites More sharing options...
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