Harnser Posted June 3, 2013 Report Share Posted June 3, 2013 The trimmed case length for my .308 is 2.005 . Today I was prepping some cases and they seemed to be some what overlong ,between 2.030 and 2.040 . I had a few tight extractions when shooting these rounds off. and had to resort to a rod down the barrel to get three of these cases out ,not a satisfactory system of extraction when out stalking . My question is ,could these long cases be causing extraction problems. ? There is no sign of over pressure at all and it is a load that I have used for many ,many years ,45 grains of vit 140 behind a 150 grain bullet . There is a possibility that these cases were not trimmed to length when loaded as 25 to 30 thou oversize does seem rather a lot . I have never had cases stretch this much before with one firing . Harnser . Quote Link to comment Share on other sites More sharing options...
al4x Posted June 3, 2013 Report Share Posted June 3, 2013 how many times have the cases been fired? Quote Link to comment Share on other sites More sharing options...
Harnser Posted June 3, 2013 Author Report Share Posted June 3, 2013 how many times have the cases been fired? I dont know for certain ,but proberbly 5 or 6 . Harnser . Quote Link to comment Share on other sites More sharing options...
al4x Posted June 3, 2013 Report Share Posted June 3, 2013 and trimmed or measured on any of those occasions? Quote Link to comment Share on other sites More sharing options...
Kes Posted June 3, 2013 Report Share Posted June 3, 2013 Harnser, you quote the correct case length from your manual. I have had chambering and ejecting problems and they have ALWAYS been oversized cases. I now routinely full length re-size the cases before reloading (advice from AL4X ) and havent had a 'jam' since. Quote Link to comment Share on other sites More sharing options...
Harnser Posted June 3, 2013 Author Report Share Posted June 3, 2013 and trimmed or measured on any of those occasions? Yes ,every time .Unless I missed them for some reason . Harnser . Yes ,every time .Unless I missed them for some reason . I always full length size and crimp . Harnser . Quote Link to comment Share on other sites More sharing options...
al4x Posted June 3, 2013 Report Share Posted June 3, 2013 Thats a little odd in that case be strange to miss that many I'd re size them again and make sure they are correct and fire a batch and see what happens. That excludes the dies from being a possible cause and then I guess you need the rifle looked at to check tolerances etc Quote Link to comment Share on other sites More sharing options...
rem708 Posted June 3, 2013 Report Share Posted June 3, 2013 I have loaded a lot of military brass. This is much thicker material than commercial and softer. The effect is the brass does not spring back and release as normal commercial does. This can cause the spent case to slightly stick. Another thing to check is take a fired case and an unfired cartridge. Slide the bullet on the unfired into the mouth of the fired case. If it’s a friction fit then you might have to internal/external turn the necks to be thinner. Could also be an indicator of over length cases engaging the rifling (effective crimp). However, this is normally combined with primer flattening (over pressure). One other effect is over polishing the brass. Bright shiny brass it does not grip the receiver well and it can cause it to stretch in the chamber and become tight. This is normally indicated by difficulties rotating the bolt. The nasty effect is excessive pressure on the bolt face!!! Quote Link to comment Share on other sites More sharing options...
Harnser Posted June 3, 2013 Author Report Share Posted June 3, 2013 (edited) Thank you all for your observations . I have loaded up a dozen rounds that I shall shoot off tomorrow . I have meticulously resized the cases and trimmed them all to exactly 2.005 . The over clean brass is interesting as I like to clean my brass until they shine like a diamond in a goats bum . Harnser . Edited June 3, 2013 by Harnser Quote Link to comment Share on other sites More sharing options...
rem708 Posted June 3, 2013 Report Share Posted June 3, 2013 I am guilty of clean brass myself The US guys who mentored me many years ago were very insistent I should not clean too much. One thing they did ABSOLUTELY insist I didn't do was to tumble loaded ammo. Apparently if you do this it can break down the coating on the propellant and can cause it to detonate with devastating results. Quote Link to comment Share on other sites More sharing options...
Redgum Posted June 4, 2013 Report Share Posted June 4, 2013 Re sizing my cases is part of my routine whether full sized or neck sized, I also am guilty of liking nice shiny cases, they get a rub down with the brasso each time though I never get a problem with my reloads. Its worth checking the trimmed cases now and again just to make sure everything is working as it should be. Quote Link to comment Share on other sites More sharing options...
coyotemaster Posted June 4, 2013 Report Share Posted June 4, 2013 I am a fan of neck sizing and checking for length at each firing. Quote Link to comment Share on other sites More sharing options...
phaedra1106 Posted June 4, 2013 Report Share Posted June 4, 2013 One thing they did ABSOLUTELY insist I didn't do was to tumble loaded ammo. Apparently if you do this it can break down the coating on the propellant and can cause it to detonate with devastating results. Ammo is tumbled before leaving the factory to remove any trace of contamination from the manufacturing process (lubrication etc.), also being shipped tens (if not hundreds) of thousands of miles by road and/or rail gives a much higher level of vibration than 10mins in a tumbler There have been tests where ammo was tumbled for several hours and in some cases days, no evidence of any deterioration to the powder was found. Quote Link to comment Share on other sites More sharing options...
dicehorn Posted June 4, 2013 Report Share Posted June 4, 2013 Harnser - I assume that one of the first things you do with fired brass is to neck size/F/L them? Are you experiencing having to put a lot of effort into withdrawing the expander button from the case when using either of your dies? Quote Link to comment Share on other sites More sharing options...
Harnser Posted June 4, 2013 Author Report Share Posted June 4, 2013 Harnser - I assume that one of the first things you do with fired brass is to neck size/F/L them? Are you experiencing having to put a lot of effort into withdrawing the expander button from the case when using either of your dies? No . Only normal pressure is required . Harnser . Quote Link to comment Share on other sites More sharing options...
dicehorn Posted June 4, 2013 Report Share Posted June 4, 2013 Federal cases? Quote Link to comment Share on other sites More sharing options...
optomist Posted June 4, 2013 Report Share Posted June 4, 2013 Had a similar problem with batch of 17 Fireball brass where the odd one which escaped a full length sizing was obviously a bit tight in the chamber, and some scuffing on bottom of case at basearound primer which is not good, however a good Firm FL resizing sorted it just to move the shoulder down a few thou, amazing that such fine tolerance made all the difference.Fireball cases certainly like to expand I also made a mistake early on with the Sizing dies, with it not quite touching the shell holder to ensure overall lenght to shoulder was correct. Tthe usual guidance appears to be to adjust the dies so it does contact shell holder and then turn it a fraction more but check your specific die instructions. Optomist Quote Link to comment Share on other sites More sharing options...
Harnser Posted June 4, 2013 Author Report Share Posted June 4, 2013 I loaded up a dozen rounds yesterday in the cases that were showing to be extra long . I was very careful how I resized and trimmed them . Every one of the rounds chambered with no problems and ejected with minimal draw weight on the bolt . It would seem that the cases being over long was my extraction problem . How they got that long I do not know . Incidently I mic up all the cases when I got back and none of them had stretched more than a thou or two . Harnser Quote Link to comment Share on other sites More sharing options...
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