At what case length is it inappropriate to keep .308 brass for reloading?

want2learn

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Sep 7, 2013
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As i understand it (according to a text i have), one should trim .308 Winchester cases to a length of 2.005 inch.

The majority of cases i was able to trim right to 2.005 - 2.006 inch.

I have a case which is 1.900 and another 4 cases that measure 2.003 inch after full length sizing and chamfer.

Is it appropriate to keep using these cases or should they be disposed of. They have only been shot twice and they look to be in fine shape.

This is for a bolt action rifle for which i am trying to learn to shoot small groups on paper. I do not have a semiautomatic .308 rifle.

Thank you
 
I would keep using them. Load em up with those few set to the side and shoot a group with your in spec brass. Then shoot these shorties into it. If you cant tell where they hit among the other in spec rounds then you will probably see that it wont make a lick of difference.
 
You'll be fine with the shorter cases. I think the max length is listed as 2.015" but your chamber may allow more room. Most of the new Lapua I have purchased over the years has been "short" at 2.000-2.003". Trim them when they get long and try to have them all at the same length. Usually pick the shortest and match the length on the rest of the cases to that.
 
Your fine load em up and shoot em. Toss em when the primer pockets fail, the necks split, or the case head starts to stretch.

Out of curiosity though are you trimming before you size or after?
 
thanks..I measure the cases before sizing, then if greater than the recommended 2.005 i go on to trim and chamfer the case and measure again...so I'm trimming after full sizing using the Forster die.

I've tried several times to measure my chamber, even purchased a Hornady OAL length gauge but i don't seem to get reproducible readings....and i've tried several times, gingerly. My best estimate after multiple attempts is an OAL of 2.8 inches using Sierra 168 grain Match King bullets.

appreciate any guidance.
 
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great idea....i'll do that with the shortest case.

.....do you fill the case with anything to help try to maintain the COAL (to prevent the projectile from being pushed into the case over time) or do you just seat a bullet as you normally would and leave it at that?
 
great idea....i'll do that with the shortest case.

.....do you fill the case with anything to help try to maintain the COAL (to prevent the projectile from being pushed into the case over time) or do you just seat a bullet as you normally would and leave it at that?
Don't need to do anything; it will stay put. BUT, Measure base to tip (COAL), and Base to ogive for the dummy round and sharpie them on the case along with a small baggie to put the round in. This way you can check the dimensions of COAL and Ogive before using as reference to ensure it hasn't changed.

The other measure is often more useful and repeatable than COAL as if the tip of bullet gets dinged, your COAL is now impossible to confirm. The Ogive, on the other hand, is forever (or almost); takes a lot of damage to get bad reading from ogive.
 
thanks..I measure the cases before sizing, then if greater than the recommended 2.005 i go on to trim and chamfer the case and measure again...so I'm trimming after full sizing using the Forster die.

I've tried several times to measure my chamber, even purchased a Hornady OAL length gauge but i don't seem to get reproducible readings....and i've tried several times, gingerly. My best estimate after multiple attempts is an OAL of 2.8 inches using Sierra 168 grain Match King bullets.

appreciate any guidance.

Just trying to understand your stated process...

You said you check OL before sizing and then if greater than 2.005 you trim...if this is what you are doing you are getting bad data and trimming your brass out of sequence. You need to measure AFTER you size because most cases will stretch a tad in OL after setting the shoulder back a few thou. Measure your OL after you size to determine if trimming is needed. If you size and your cases are between 2.005 and 2.010 I would leave them along and trim the next reload. If this is already what you are doing ignore this I was confused by your last message.

Now when you say measure the chamber are you trying to measure your chamber for case shoulder set back during resize or are you trying to find the lands for a specific bullet COL because it sounds like you are trying to get a lands measurement correct?
 
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thanks..I measure the cases before sizing, then if greater than the recommended 2.005 i go on to trim and chamfer the case and measure again...so I'm trimming after full sizing using the Forster die.

I've tried several times to measure my chamber, even purchased a Hornady OAL length gauge but i don't seem to get reproducible readings....and i've tried several times, gingerly. My best estimate after multiple attempts is an OAL of 2.8 inches using Sierra 168 grain Match King bullets.

appreciate any guidance.

I wasn’t talking about the distance to the lands. I was talking about the distance from the breechface to the beginning of the freebore. That’s the number limiting your case length. Most factory 308 chambers are .050” longer than min trim length. The shortest match reamer available is .025” longer than trim length. So you can let your cases grow if you want. Longer necks are desirable when you are shooting 155gr bullets close to the lands because these projectiles don’t have much of a shank for the neck to hold on to.
 
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thanks..I measure the cases before sizing, then if greater than the recommended 2.005 i go on to trim and chamfer the case and measure again...so I'm trimming after full sizing using the Forster die.

I've tried several times to measure my chamber, even purchased a Hornady OAL length gauge but i don't seem to get reproducible readings....and i've tried several times, gingerly. My best estimate after multiple attempts is an OAL of 2.8 inches using Sierra 168 grain Match King bullets.

appreciate any guidance.

Measuring OAL will just make you batty. Measure Ogive to Head (OH). Look at the the tips of your bullets, then measure their length. Inconsistent, right ? That inconsistency carries directly over to loaded round OAL. Your seating die presses the bullet into the case via the Ogive, not the Head.
 
are there easy and reproducible ways to measure both of these dimensions (distance to lands...and distance from freeborn to breach face) at home?

Yes. Simple and easy.

Full length size a case but adjust the shoulder length for zero clearance. Cut a slit in the case neck all the way into the shoulder using a dremel or needle file or similar. Stick a bullet into the neck and push the case into the chamber until you feel the case bottom out. Then push out the round with a cleaning rod and measure the oal.
 
are there easy and reproducible ways to measure both of these dimensions (distance to lands...and distance from freeborn to breach face) at home?
For distance to the lands you can use the slit case 918v discussed, see how far the bullet slides into the case when chambered.
1547217664393.png



The cleaning rod method




the hornady OAL tool
1547218002188.png



Your chamber itself




Your chamber itself is really only with a sinclair gauge or similar
 
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Max is 2.015 for 308. Most will trim .010 from max, so most will trim 308 to 2.005 recommended...... I’ve used brass down to 2.000 and try not to go under that.... I’d personally say that 1.900 is too much personally. Put it this way, an 1/8 of an inch is .125”..... maybe 1.998ish, but not 1.900”
 
Snuby, thanks....i should clarify that i measured all the cases before sizing to make sure they were ok to size....i only trimmed after full length sizing as needed. I'm a beginner and as such was over cautious by measuring before and after.

I want to be very safe and consistent so i really appreciate all the help, guidance and parameters.

Will work at securing not only COAL but also chamber length in my quest for learning and excellence.
 
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I was making sure I read it right.
I may get my lee press mounted on the new bench today or tomorrow.
I have a new 4 die set "308" I'm setting up next.
Have several hundred rounds fire formed to my sons gun.

He was using his dillon set but sure we can get better results on single stage.
Not knocking dillon at all, I don't know how to get the best accuracy out of it I'm sure.
I am also not about to single stage 9mm, 38, 45, 357, etc except for development.

I would toss that one piece of brass that is 1.900 and use the rest.