Can a Case be too Short?

Dom

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Just curious, as I end up with short cases quite often, I think mainly due to using a VLD inside chamfer. Anyway, I no longer trim cases .010 under max case length, usually .005 under as I know they'll get shorter over time. But how short is too short to not use? I'm kind of a miser, and unless they are over .015 short or shorter generally use them. I get leary if they are shorter than .015 though, or do folks use cases much shorter? Also depends on what I'm going to use them for, if competition or hunting, I'm more picky, but if just shooting paper I just load em up.
 

bob4

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Can't answer your question specific. But I am like you. I trim .005 under once they reach max length. Probably once only till they reach their life span. I'm not benching so that much makes no difference.
 

J E Custom

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The only problem with trimming only .005 under Max is that all chambers are not equal so you must first establish the actual length of your chamber . If this is not done, any carbon build up can cause excessive pressure. I would recommend .010 less than the maximum your chamber will allow.

As to how much shorter you can trim a case before it becomes unusable in my opinion, I draw the line at .040 to .050 thousandths short depending on the cartridge design. Trimming can be minimized by sizing only enough to chamber the round. Most cartridges have neck lengths of over .300 thousandths long except some of the 22 caliber cartridges which are normally around .250, so .040 isn't much of a decrease in %.

Neck tension isn't as much of a problem with short necks as Bullet alignment is, so loading short neck cartridges requires more care when seating the bullet.

J E CUSTOM
 

Dom

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My cases get longer not shorter. How much are you bumping the shoulder back something seems amiss now my brass does seem to not grow very much after the first few firings.
Don't get me wrong they also get long, however for whatever reason after a couple reloadings there's always a few that are short short. Lot of Hornets get short, just a small case to start with. Last batch was 6,5x55, about 15 somewhat short. Not as many on the larger cases like 30-06, 300, 9,3 etc. Nothing I'm doing wrong, just curious what cutoff others use on short cases.
 

MagnumManiac

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Feb 25, 2008
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I don’t trim until ALL the cases in a batch require it and I measure to the end of ALL my chambers.
I’ve got reamers here, 3x ‘A191’ reamers, and their prints, but on one the reamer doesn’t match the print.
The actual length is shorter than stated.
I run the brass at .010” shorter than the chamber end, it gets trimmed at .005” short of the end.

Cheers.
 

SilverbulletMAG

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Dec 12, 2018
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MN
I have a Lyman trimmer that I've about had it with. The set screw is wimpy and more often than not I'll have everything perfectly dialed in, checking the first several cases to ensure everything is good to go. Inevitably, as soon as I put the calipers down and start rolling through a few more cases, I'll check another case and be waaaaay too short. Preventable but still annoying.
Moral of the story, I use those reeeeeally short cases as sighters/fowlers and hit within the margin of error of the properly trimmed cases. Obviously a little common sense goes a long way here. Don't cut the neck off and try to seat in the shoulder....lol
 

jpope02

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Apr 3, 2012
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179
Are there any negatives seating the bullet beyond neck base as my 6.5 Creed has a long free bore and when I seat .015 off the lands the bearing surface edge is slightly up the neck (.040") from the start of the shoulder ?
 
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entoptics

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Jan 16, 2018
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Awhile back I bought 300 MAI cases (Norma made) for my 300 WM and another 300 for my buddies.

After sizing, but before first firing, they averaged 2.602" ± 0.003" That's 0.018" short of SAAMI maximum, and a fairly wide spread. I was initially a little concerned, as the 300 WM myths and legends indicate it has a short neck already, but I had no issues at all with them. I fired them all a couple times, then cut them back to 2.610 (0.010" off SAAMI).

IMO, unless your gun is a real bug holer, a couple percent variation in overall neck length doesn't make much difference, and as long as you're aware of the "carbon ring", you can probably run them pretty short without much issue.
 

jpope02

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Apr 3, 2012
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179
In general is OK to seat a bullet .040 up the neck to compensate for a short case or a long throat chamber?
 

JohnMill

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NE IL. Behind enemy lines
I hav not read all the replynnot see this reply so will stop now so forgive if I ster on anyone.
I'm with JE. I always measure each chamber with the Sinclair gauge ( the little slug that goes inside a trimmed down case) It's a pain but exact. I've actually not found a chamber I had to trim for all are longer than spec all are longer than necessary bgut you should measure anywayI ca
The only problem with trimming only .005 under Max is that all chambers are not equal so you must first establish the actual length of your chamber . If this is not done, any carbon build up can cause excessive pressure. I would recommend .010 less than the maximum your chamber will allow.

As to how much shorter you can trim a case before it becomes unusable in my opinion, I draw the line at .040 to .050 thousandths short depending on the cartridge design. Trimming can be minimized by sizing only enough to chamber the round. Most cartridges have neck lengths of over .300 thousandths long except some of the 22 caliber cartridges which are normally around .250, so .040 isn't much of a decrease in %.

Neck tension isn't as much of a problem with short necks as Bullet alignment is, so loading short neck cartridges requires more care when seating the bullet.

J E CUSTOM

have
Just curious, as I end up with short cases quite often, I think mainly due to using a VLD inside chamfer. Anyway, I no longer trim cases .010 under max case length, usually .005 under as I know they'll get shorter over time. But how short is too short to not use? I'm kind of a miser, and unless they are over .015 short or shorter generally use them. I get leary if they are shorter than .015 though, or do folks use cases much shorter? Also depends on what I'm going to use them for, if competition or hunting, I'm more picky, but if just shooting paper I just load em up.
 

wonderman4

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Oct 7, 2013
Messages
193
Location
South Texas
If the case is shorter in the neck, then bullet pull will not be the same due to less contact with the bullet/neck.

I would not expect tack driving accuracy. Other than that, nothing else matters unless you are using rimless straight wall cases that headspace off the mouth of the case (think 45ACP et al).
 

CO_Guy

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Nov 16, 2018
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1,382
Location
CO, USA
I keep my trim at specified trim length and keep my inside and outside chamfers to a minimum, just to seat ok and to avoid any lip you can feel from the outside. In short, I try to remove as little case material as possible, to maximize case life.
 
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