Revo357 Posted February 13, 2015 Share Posted February 13, 2015 Hello everyone, I have purchased a .38 supercomp open gun and it is failing to chamber completely. Every couple of rounds will cycle and chamber every time but others will get caught right at the chamber roof during the tip-over point. I'm fairly new to reloading and I've tried various bullet lengths from 1.240-1.270 and it all continues to result the same. I'm hoping it's just a spring strength issue. Any experience with this out there? Thanks for your help, Lucas B. Link to comment Share on other sites More sharing options...
Build4u Posted February 13, 2015 Share Posted February 13, 2015 If you have the barrel out take a picture of the corner where the ramp meets the chamber. That sounds like the point where extractor tension, cartridge oal, and the corner of ramp to chamber all come in to play. A lot of smiths leave that corner alone providing maximum support for the case. I frequently ease that corner over for total reliability. The case wall needs to be supported at top of ramp however the extractor groove does not. Drop a round in the barrel and take a look. Let the builder know it is not running especially if you are not familiar with doing this. Loading a flat point/hollowpoint bullet with the truncated cone type profile long can create that type of stoppage as well. Some flat point change profile faster than a round nose profile and bind at ramp corner to top of chamber. Also if you have an Aftec extractor I ended up running a spring in the front pocket only. When reinstalling you have to slide a small wire or straight o ring pick in beside to tip the spring backer straight to get the extractor back in. Watch the brass eject to make sure it is good. Link to comment Share on other sites More sharing options...
Guest Posted February 13, 2015 Share Posted February 13, 2015 If I read it right it sounds like the bullet is ramming into the top of the chamber and stopping before it cams over to slide into the chamber. So yes, it may be that the recoil spring doesn't enough oomph. If you are running a really light recoil spring I'd recommend bumping up to something around 9-12 pounds (assuming you are making major pf) and see if that helps. If you are already running a spring in that range it may be a mag tuning issue where the feed lips aren't releasing the round soon enough and the round can't reliably make the more acute change of direction. Also, it might be a feed ramp issue (rough or cut wrong), an extractor issue (case rim isn't sliding up under the hook smoothly), a slide fitment issue (too much friction on the rails or not broken in yet), or even a barrel fit issue. If you are using JHPs might want to try round nose bullets to see if that helps. For most of the double stack 38 supers running an OAL of about 1.250" for round nose and 1.235" for JHP seems to work well (JHPs need to be a little shorter to run in the mag without dragging their nose). I'm almost willing to bet it is a combination of things and not just an OAL or spring issue so be patient and work one thing at a time. If you have a shooting buddy or shoot at a club with some experience open shooters I'd ask one of them to take a look. If you bought the gun used then asking the previous owner could be helpful. Good luck. The learning curve for running an open gun can sometimes be steep! Link to comment Share on other sites More sharing options...
Durtarg Posted February 13, 2015 Share Posted February 13, 2015 I run mine at 1.235 OAL. Are you chamber checking your rounds? If not that may be your issue. If you are and they are passing; it may be your extractor. If you have an AFTEC extractor, pull it out and see if it has both springs. If it has both, take out the rear spring and see if that solves the issue. I was having some chambering issues and removing the rear spring from my Aftec solved it. Just a process of elimination with open guns Sent from my iPhone using Tapatalk Link to comment Share on other sites More sharing options...
Aircooled6racer Posted February 13, 2015 Share Posted February 13, 2015 Hello: Sounds like the feed lips on your mags is too narrow. Make them 0.357" front to back and see if that works for you. Do one mag first. Thanks, Eric Link to comment Share on other sites More sharing options...
Revo357 Posted February 13, 2015 Author Share Posted February 13, 2015 Thank you guys for all the information! I'll see if I can post some pictures later on today to see if a visual would be helpful. I've been loading 124gr Hornady FMJ-RN to 1.250 as the starting point and once I experienced feeding issues I started to play with the OAL. I plunk tested the chamber and I went up to 1.275 and the round still spun freely with full support of the casing, but didn't want to go higher because 1.280 is the recommended max for .38 super. And for what it's worth I have a Schuemann Ultimatch barrel. The ramp/chamber corner doesn't seem to be abnormally sharp or angled to effect feeding but I'll let someone more experienced than I make that determination. Yes Bamboo, that is the issue I'm having and thank you for the variable listing. I'll have to measure the feed lips for sure and try that out. Just trying to get a list going to weed possibilities out. So far I'll be looking at recoil spring, ejector, extractor, ramp/chambering, and magazine feeds lips. Thanks again, great info guys. Link to comment Share on other sites More sharing options...
stardust tommy Posted February 13, 2015 Share Posted February 13, 2015 load a round without the extractor and see if chambers if it rides the link maybe you have a 3 point jam and check your mags like Aircooled6racer told gr Tom Link to comment Share on other sites More sharing options...
Revo357 Posted February 13, 2015 Author Share Posted February 13, 2015 If it did come to modifying/replacing the extractor or ejector is that something I should attempt on my own or send it? I've read about it some but reading and doing are not the same. Just ordered some Wolff springs, 10, 11, and 12 pounds just to play with since I am trying to go major, but for now I just want the thing to function! Link to comment Share on other sites More sharing options...
Glk21C Posted February 13, 2015 Share Posted February 13, 2015 1.235 oal is recommended for S_I style 2011 mags to assure reliable feeding Out of the mag. Link to comment Share on other sites More sharing options...
Foxbat Posted February 13, 2015 Share Posted February 13, 2015 Also, check the crimp on your ammo. I had similar situation, with one gun randomly refusing to chamber a round. It turned out there was insufficient crimp. I increased it just a tad, and the problem disappeared. Link to comment Share on other sites More sharing options...
Revo357 Posted February 14, 2015 Author Share Posted February 14, 2015 I'm not against trying to go shorter or adding more of a crimp. I just don't want to go too short and cause problems. What's your diameter of the crimp your using? And specific bullet diameter? Thank you. Link to comment Share on other sites More sharing options...
dons Posted February 14, 2015 Share Posted February 14, 2015 (edited) Foxbat beat me to this, I've seen a number of crimp issues in 1911-type pistols. Resized 38 Super cases measure .380 for me, so I try to crimp to about .378 or .379 at the mouth, but the measurement is difficult because the area you're trying to measure is tapered. Brass can also vary in length. I just grabbed a random many-times-fired RP 38 Super case that measured .878, and new Starline I have measures .896. So you want to make the crimp adjustment on your die for your average length cases to make sure you at least remove all the "bell" from your case mouth. I need to caution you about over crimping also, it can distort the bullet to a point that (in some guns) it doesn't stabilize. I have 2-38 Super open guns, ammo that's fine in one will keyhole in the other. One other thing to check for with your feeding issue is the breech face. make sure there are no burrs or rough spots. As always, these comments are based on my own experience. YMMV Edited February 14, 2015 by dons Link to comment Share on other sites More sharing options...
Toolguy Posted February 14, 2015 Share Posted February 14, 2015 Sometimes the rim of the case can hang up on the sharp edge of the firing pin hole. Check for burrs, maybe put a tiny chamfer on the hole. Link to comment Share on other sites More sharing options...
Revo357 Posted February 15, 2015 Author Share Posted February 15, 2015 Thanks for the tips, disassembled the slide and cleaned breech face and polished up the extractor for the case rim to slide up easier, hopefully. I'll be trying different crimp levels in small increments as well as different oals's again. Checking the measurements on my mags as we speak. Won't have a match until March so I won't be able to discuss the issue with fellow shooters, getting good information from you guys though. Link to comment Share on other sites More sharing options...
Guest Posted February 16, 2015 Share Posted February 16, 2015 If you haven't done so yet, make up some dummy rounds (no poweder, no primer) and hand cycle them. Might reveal some of what is going on. Link to comment Share on other sites More sharing options...
Revo357 Posted February 16, 2015 Author Share Posted February 16, 2015 (edited) That's something I haven't shared, when I manually cycle rounds it will extract and feed each round perfectly. Only when I'm actually shooting the gun will it have failures to chamber. That's what got me thinking it may be a spring issue but hopefully this will shine some more light on the situation. Thank you Edited February 16, 2015 by Revo357 Link to comment Share on other sites More sharing options...
Durtarg Posted February 17, 2015 Share Posted February 17, 2015 How's it going with trying to figure out the issue? Have you found the cause or made any adjustments to fix it? Link to comment Share on other sites More sharing options...
Revo357 Posted February 18, 2015 Author Share Posted February 18, 2015 I finally revieved my new wolff recoil spring in and loaded up some rounds but haven't got to shoot since there is a foot of snow outside. I increased the taper crimp a bit as well. I really hope this helps the issue. Haven't messed with my magazines as of yet but that is my next step in the process. Link to comment Share on other sites More sharing options...
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