Azone41 Posted March 12, 2007 Share Posted March 12, 2007 I have a open gun in 9mm Major (Shorty). It was built by a Very well known Gunsmith. This past weekend it started doing something that it has never done before. During 3 stages it would fail to extract the fired round. Now of course the first thing to look at is the extractor (an AFTEC). I took the gun apart checked the extractor and it would hold the loaded round against the breachface perfectly a very knowledgeable GM also looked and confirmed that there was plenty of tenision on the extractor. I could not find my bag of extra Aftec springs when I got home so I ordered a new extractor and extra springs form Chuck @SC. My question is there anything else I should check. The rounds are 166.4 PF using HS-6 loaded to a length 1.135 using spacers in STI mags. I ordered the new extractor just in case. What does everbody think????. Link to comment Share on other sites More sharing options...
dfwmiket Posted March 12, 2007 Share Posted March 12, 2007 (edited) Don, FWIW, I recently bought wifey an Open gun ( you may have seen it shine up at the DTR Feb. match).....and with it, it too had some of the same issues. I also changed springs.... main thing I've found is it doesn't do it when the PF is about 173. Weird, I know.....but it works, so I'm sticking with it. I'm anxious to hear the other replies to see if I can learn more.... -Mike Edited March 12, 2007 by cnemikeman Link to comment Share on other sites More sharing options...
ipscbob Posted March 12, 2007 Share Posted March 12, 2007 Sounds like possible high pressure issues. Any other pressure signs ? Flattening primers or excessive case head expansion? Link to comment Share on other sites More sharing options...
Azone41 Posted March 12, 2007 Author Share Posted March 12, 2007 (edited) I was also thinking about high pressure making the case swell to much for the extractor to pull out the fired round. I looked at the brass and the primers had some pressure signs but not excessive. I was thinking about loading a little longer if the springs don't fix the problem. I did however try some of the rounds my wife uses (loaded to factory minor) and it did it once with those also. I have been reloading for 30+ years so I keep a very close eye out for excessive pressure. This is one of those things that you really just have to elimanate one thing at a time to find out the problem. In order to get to 166.4 I had to use 8.9 grns of HS-6 (Win Small Rifle primers) and I loaded short so I would make a little more pressue. The fired rounds have a very clear indent in the primer and no ridges. Edited March 12, 2007 by Azone41 Link to comment Share on other sites More sharing options...
XRe Posted March 12, 2007 Share Posted March 12, 2007 It was built by a Very well known Gunsmith. I appreciate you trying to maintain anonymity - but your avatar tells us who it is... I looked at the brass and the primers had some pressure signs but not excessive. Consider that, by the time the primer starts to show flattening (not slight flattening out of the corners, which is normal, but more than that...), you're pretty high up the pressure scale... High pressure combined with a (relatively) rough-ish chamber can cause sticking. So can less than ideal brass. Clean the barrel thoroughly, and examine the chamber carefully for erosions or rough spotsThe workings of the gun depend upon the brass to expand and seal the chamber, and then retract as soon as pressure drops - if the brass doesn't retract off the case walls.... Another possibility is that the gun is unlocking slightly prematurely, and the brass hasn't had time to retract off the chamber walls. Being that you've got a shorty w/ what appears to be a Ti comp, you're in the corner of the time envelope there, due to the nature of the gun (the light weight of the slide, barrel, and comp cause it to get moving quicker than a heavier arrangement...). If your recoil spring has weakened some, it my be traveling out of battery just a hair too soon. What has your gunsmith said about it, at this point?? BTW - if you haven't asked him, yet, consider asking your gunsmith his opinion. He knows his system better than anyone else!! Link to comment Share on other sites More sharing options...
basman Posted March 12, 2007 Share Posted March 12, 2007 I had a the same problem, replaced the Aftec front spring only and 100% again. Link to comment Share on other sites More sharing options...
Azone41 Posted March 12, 2007 Author Share Posted March 12, 2007 Dave its not my Bedell gun that was having the problem. That gun is a 38 super. I almost put in the first post that it wasn't the gun in my avatar then decided not to do it and of course someone jumped right on it. The problem was with my other open gun in 9mm. Link to comment Share on other sites More sharing options...
Azone41 Posted March 12, 2007 Author Share Posted March 12, 2007 Dave Very informative post. I changed the recoil spring the week before the match and used it for a match that weekend I changed it with no problems. I checked the chamber very close with a strong light and its as smooth as a babys butt. The unlocking early gets me to thinking , I was told by the gunsmith that the gun was built to run best @ 172 pf. I bought the gun for my wife and she has only run factory minor rounds through it. I put a 2lb lighter recoil spring in the gun for my wife to run the minor rounds and when I changed the spring I used the same weight spring. This is a VERY fast cycling gun and I just worked up the load for this past weekend the week before.. It worked fine then but I haven't had alot of experience with 9mm major because I always shoot my 38 super. I got am email from Chuck today that me order has shipped and should be here by wed. So with all this info I will start checking things out htis comming weekend Thanks for all the help. Link to comment Share on other sites More sharing options...
scirocco38s Posted March 12, 2007 Share Posted March 12, 2007 Out of curiousity , is the brass the same make or mixed? 1 of the guys I shoot with has found that as long as he runs winchester brass, he has no problems, If he runs mixed headstamps he gets irregular ejections and occasional extraction malfunctions. I dont know but maybe that could be an issue. I also know of some shooters in production having issue shooting remington 9mm brass(this is factory loaded ammo) could be the same issue even though different applications.. Link to comment Share on other sites More sharing options...
9x21 Posted March 12, 2007 Share Posted March 12, 2007 Sounds like possible high pressure issues. Any other pressure signs ? Flattening primers or excessive case head expansion? I had the same issue, using 9x21 & 540(hs-6) FAILURE TO EXTRACT at a major match (ate a stage) My gunsmith was present, took the pistol to the shop, found no issues with AFTEC or pistol.... My loads all seemed to crony good till I dug deeper. Lets say I narrowed the problem to my press & powder measure. It was HIGH PRESSURE Once corrected, runs like a champ What type of press do you use? Link to comment Share on other sites More sharing options...
shooterbenedetto Posted March 13, 2007 Share Posted March 13, 2007 I hope brass was not NICKEL? i had problems with nickel. make sure it is brass. just my input. Link to comment Share on other sites More sharing options...
RC1 Posted March 13, 2007 Share Posted March 13, 2007 1.135 oal seems way short to me. I would not go any shorter then 1.155 oal. I would be willing to bet that loading that short, is probably causing the pressure to go to high. Link to comment Share on other sites More sharing options...
J.L. Hardy Posted March 13, 2007 Share Posted March 13, 2007 (edited) In my opinion you are loading too short at 1.135 and the powder is faster than what I reccomend. Both issues are causing too much pressure. You should be loading to 1.155 which is twenty thousandths longer. Lengthening the round may clear it up. I also don't reccomend nickle brass. As it contracts less after firing. If you are using nickle try some plain brass with the same headstamp and see if it clears up. I think we all know the difference when reloading nickle brass because you can feel the resistance when resizing. 9mm major is highly succeptable to sticking in the chamber causing the malfunctions you describe. Edited March 13, 2007 by J.L. Hardy Link to comment Share on other sites More sharing options...
XRe Posted March 13, 2007 Share Posted March 13, 2007 I almost put in the first post that it wasn't the gun in my avatar then decided not to do it and of course someone jumped right on it. That figures.... I put a 2lb lighter recoil spring in the gun for my wife to run the minor rounds and when I changed the spring I used the same weight spring. So, you put in a spring that was 2# lighter than what the gunsmith recommended for major loads - because you were running minor loads in it. That's all good. Then, you swapped the spring with the same weight (which is 2# lighter than the original spring that came in the gun), and then started to run major loads in it? One potential first step is pretty obvious, if I read that right - heavier recoil spring by 2#. J.L. builds a lot of 9mm Major guns, on short recoil systems (which tend to cycle faster than full length systems). He knows his stuff in that regard. All the things he mentioned factor in to the same problem as the recoil spring keeping the gun locked up long enough - the brass isn't getting off the chamber walls quickly enough (or, at all, possibly...). Basically, you've overstepped all of the tolerances built into the system, and changing any one of those things could get you back to running - but you should look at them all to gain back as much as you can. Freshly worked up loads points at pressure, too - this is a new load for the gun, so its not like you had a previously working gun that then decided to stop working... So, longer OAL (which gives you a lower spike in the pressure curve, even if you need more powder), consider a slower powder possibly (though plenty of folks run HS-6 successfully - I used to in 9x21, for instance), go back to the original recoil spring weight, and no nickel brass (if you've been using any). See if that helps... I suspect seeking a lower pressure load will be the bulk of it, though... Link to comment Share on other sites More sharing options...
HSMITH Posted March 13, 2007 Share Posted March 13, 2007 Keep in mind that mainspring tension has a lot more to do with unlock timing than recoil spring. The recoil spring has very little to do with unlock timing, firing pin stop geometry and mainspring tension are the only 'user' adjustable ways to alter unlock timing to a significant degree. Link to comment Share on other sites More sharing options...
J.L. Hardy Posted March 13, 2007 Share Posted March 13, 2007 HSSMITH, You are absolutely correct. Even though I do not alter the geometry of the radius of the FP stop, I only use 19# mainsprings. Nothing Lighter. Maybe this gun should have a new one installed in case the one in there has weakened. Springs do that some times if they don't take a proper temper. Also slower powder causes the gun to stay locked up longer, due to the powder burning in the comp instead of being burned up in the barrel. A light recoil spring combined with a weakened mainspring can cause serious problems. Link to comment Share on other sites More sharing options...
Carlos Posted March 13, 2007 Share Posted March 13, 2007 Agree that the OAL is shorter than it should be (why load any shorter than 1.150+??) but the real issue is not the peak pressure, but rather, WHEN during the firing cycle the pressure spike happens. A longer OAL should cure the problem, although as you know, you may have to adjust the charge to compensate - especially since you are so close to the PF anyway. Link to comment Share on other sites More sharing options...
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