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9/29/2013 12:58:29 PM EDT
well,i had built 200 rds of 308 only to find out that they would not chamber due to not enough shoulder set back.so...i beat them all apart to try again.i ran them thru the sizing die after readjusting it.all is good there now.they all sit in the dillon case gauge as prescribed...now..,.im finding after if loaded them again ,that a few of the cases are slighty longer than 2.015..so..what to do?beat them apart again?when i measure some factory cases,they measure 2.00 almost so mine definatly seem longer.the thing that im most confused about is the head space length looks fine,so will the gun tolerate a slightly longer case?i guess im wondering if there is a margin of error on case length?
9/29/2013 1:15:33 PM EDT
[#1]
Quoted:
well,i had built 200 rds of 308 only to find out that they would not chamber due to not enough shoulder set back.so...i beat them all apart to try again.i ran them thru the sizing die after readjusting it.all is good there now.they all sit in the dillon case gauge as prescribed...now..,.im finding after if loaded them again ,that a few of the cases are slighty longer than 2.015..so..what to do?beat them apart again?when i measure some factory cases,they measure 2.00 almost so mine definatly seem longer.the thing that im most confused about is the head space length looks fine,so will the gun tolerate a slightly longer case?i guess im wondering if there is a margin of error on case length?
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i try not to have my cases trimmed longer than 2.015, I have had them at 2.000 and a little shorter with no problems whatsoever.. are you not using a case length cutter? are you shooting a bolt action or semi auto? some guns only like shooting the same ammo after reloading because of pressure which may cause it not to chamber and extract
9/29/2013 1:22:39 PM EDT
[#2]
i have a lyman case trimmer is all.im loading these for my ar10.on the dillon case gauge there seems to be 3 steps.the factory round that i set into the case gauge appears to be at the bottom step and the cases that im concerned about seem to be just above the top step.fortunatly its not all 200 this time time,only about 25 rounds.
9/29/2013 1:39:36 PM EDT
[#4]
Quote History
Quoted:
i have a lyman case trimmer is all.im loading these for my ar10.on the dillon case gauge there seems to be 3 steps.the factory round that i set into the case gauge appears to be at the bottom step and the cases that im concerned about seem to be just above the top step.fortunatly its not all 200 this time time,only about 25 rounds.
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i would just get the cases to the listed 2.015 or shorter to see if they chamber and extract.. if ur cases are on the top step (not flush wth your case gauge) you need to adjust your full length sizing die
9/29/2013 1:48:16 PM EDT
[#5]
a few are on the top step at the aol end of the gauge.i thought the only way to change that was to trim the cases?on the head space end(primer end)they sit just under the step.thanks
9/29/2013 4:11:57 PM EDT
[#6]
One end of the gauge is for headspace, the other end for OAL of the case.



I trim to 2.005 which is the recommended "trim to" length.
9/29/2013 4:28:50 PM EDT
[#7]
http://www.sinclairintl.com/reloading-equipment/measuring-tools/case-gauges-headspace-tools/sinclair-chamber-length-gage-prod32925.aspx

Try this little tool from Sinclair.  Follow instructions provided.  You may find that your rifle throat is longer and will allow longer than 2.015 case length and you do have a tolerance.  My mil surplus rifle throats are longer and thus I do not have to trim as often.
9/29/2013 5:28:27 PM EDT
[#8]
man thats a cool looking tool!to bad its not offered in 308!
9/29/2013 9:45:52 PM EDT
[#9]
Quote History
Quoted:
man thats a cool looking tool!to bad its not offered in 308!
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I can let my necks grow to the tune of a 2.019" case length, on a Savage 10FP LE2b.

2.015" is SAAMI MAX.

When you bumped the shoulders back, did you remove your expander ball?

You might have stretched the necks/shoulders back out a little bit, if you didn't.

Get a Redding Body die and the next time this happens, you won't have to break them down to bump the shoulders back, just lube them up a bit.

Chris
9/29/2013 11:17:14 PM EDT
[#10]
Quoted:
man thats a cool looking tool!to bad its not offered in 308!
View Quote


1-800-717-8211

It IS offered in .308, I have one.  Call Sinclair to confirm, but pretty sure its the one marked .30 caliber.  

The instructions guide you in making a dummy case that is cut down shorter than normal to hold the gage.  Make sure if you order it, you understand and follow the instructions.  Sinclair has excellent tech support and you can always call and talk to them about almost anything reloading whether you buy their tool or not.

The previous post has a Savage bolt gun with a chamber that allows cases to grow to 2.019.   On my LR-308 chamber length is 2.030, and M1A its over 2.040.  I will not let the brass grow that long, but I don't have to trim when brass goes a little over 2.015 either.

Trimming to a consistent length aids in accuracy in addition to preventing problems.  However when I resize and do not have to trim, even though case length may vary slightly, it has not affected accuracy.  When I do trim, I dont have to trim the brass as soon as it exceeds 2.015 or the way down to 2.005.  The net effect is longer brass life.
9/29/2013 11:18:31 PM EDT
[#11]
NT, accidental repeat.
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