I'm just getting into this reloading-and one question I have is-how do you know when a cartridge has to be trimmed?[I understand the brass stretches and all that-but what determines the correct length?]And-in something like my low velocity 2000 fps 9,3x57-how many times could I reuse the brass,assuming it has to be trimed?
Cartridge Length
- Thread starter ratherbefishin
- Start date
The correct length of the brass should be listed in the reloading manual for that caliber along with all the other dimensions.
How often brass should be trimmed depends upon several factors. Light loads will stretch brass less.
How concerned are you about doing everything possible to acheive maximim accuracy ?
Some reloaders may trims cases every 3 o4 loads. Some never.
How often brass should be trimmed depends upon several factors. Light loads will stretch brass less.
How concerned are you about doing everything possible to acheive maximim accuracy ?
Some reloaders may trims cases every 3 o4 loads. Some never.
Sierra has good guides in their loading manuals showing the case length and a "Trim To" length.
I take the length shown in the manuals as Max case length. I usually trim .010 shorter than listed case lengths.
For example....Lee shows case length of a 223 Rem cas to be 1.760. I would trim these to 1.750 then chamferring will extend the lip of the case a few thou to give a case length of 1.752-1.753ish.
Check length again after firing to see how much it is being stretched. Chances are, first firing after trimming will have a more substantial stretch than subsequent firings.
Depending on the cartridge, you may get 2, 3, 4, 5 or more firings before re-trimming.
I take the length shown in the manuals as Max case length. I usually trim .010 shorter than listed case lengths.
For example....Lee shows case length of a 223 Rem cas to be 1.760. I would trim these to 1.750 then chamferring will extend the lip of the case a few thou to give a case length of 1.752-1.753ish.
Check length again after firing to see how much it is being stretched. Chances are, first firing after trimming will have a more substantial stretch than subsequent firings.
Depending on the cartridge, you may get 2, 3, 4, 5 or more firings before re-trimming.
Get a Lee case trimmer & length gauge for the calibers you reload for. They are simple, inexpensive & easy to use. Just make measuring & trimming a part of your case prep routine. Full length resizing will stretch your brass. If you are using the cases in the same firearm, consider just neck sizing your brass. By using neck sizing, your brass will last longer, & your accuracy should improve slightly also. I use neck sizing mainly to extend the life of my hard to get brass. NOTE neck sizing is NOT recommended for semi-auto's, pumps, & lever actions.
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I'm with glang1 on this one. Some solid advice...I only neck size my 22-250 brass as it is all shot through the same rifle. I trim case length every time I reload, but that's just me being anal...I like all my casings to be the exact same length
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I'm with glang1 on this one. Some solid advice...I only neck size my 22-250 brass as it is all shot through the same rifle. I trim case length every time I reload, but that's just me being anal...I like all my bullets to be the exact same length
The length of your brass has nothing to do with the over all length of your loaded round. If you had brass trimmed to book length and brass +.010" longer why would your "bullets" not be the exact same length?
I have shot brass .015" to .017" longer than the book spec. in a match chamber without any problems. Full length resizing will stretch a case more than shooting it will.
I'm with glang1 on this one. Some solid advice...I only neck size my 22-250 brass as it is all shot through the same rifle. I trim case length every time I reload, but that's just me being anal...I like all my bullets to be the exact same length
I too was wondering what case length had to do with COAL
I'm also wondering where this guy is going to get a Lee case trimmer & length gauge in 9.3x57
I must learn not to rush when typing...what I meant was I like all my casings to be the same length before priming, charging and seating a bullet!
