Lapua 308 cases

[ANDY T]

Hi
I am new to reloading and i have a question about case length.
What length should i trim my cases to I know its 2.015 is the max.
Would it be ok if i went down to 2000 or is that to much.

Lapua 308 case

Andy

 

[whiskey08]

how much neck do you need to seat bullet where you want it. Some guns need all the neck you can get to touch lands etc. I trim mine to 2.014, I dont like cutting more brass than i need to, Im trying to make the cases last as long as possible.

Also i only partial size the necks so with a longer neck i have enough unsized neck to center in chamber and still enough to hold bullet.

 

[lightman]

I recommend using the trim to length listed in your loading book.You can buy/make a simple tool to meausure your chamber and trim your cases close to this,but for a beginner,I would use the book.For a 308,that number is 2.005.There is no need and to trim shorter than this. Lightman

 

[fdshuster]

The trim to lengths listed in the reloading manuals are "one-size-fits-all", designed to be "safe" with those chambers that are cut to minimum lengths. Take the guesswork out of the equation, get one of the Sinclair chamber length gauges ( page 37, catalog# 2010-B, $6.95) and take the actual measurement for the length of your (emphasis on "your") chamber. Record that dimension then decide what maximum length you are comfortable with. I use .005" shorter on my benchrest ctgs., (6BR: 1.570", trimmed to 1.565"), and the factory ctgs., at .010", like the 223 Rem., 1.770" trimmed to 1.760". I've measured factory chamber lengths and found some of them to be as much as .035" to .040" longer than max case length. Follow the trim-to lenghts in the manuals and you could be creating a very long gap in front of the case mouth when the round is fully seated in the chamber.

 

[KevinThomas]

Hi Andy,

Feel free to take them down to 2.000" even if you want to, it won't cause any problems. This was the "standard" trim length most of us used to use when the M14/M1As and 308 bolt guns dominated the high power game. Won't have a thing to do with case life, as the reasons we lose cases has nothing to do with trim length, and more to do with load levels, primer pockets, neck splits, stretching relating to head separation, that sort of thing. Case trimming is much more of a safety issue, done to ensure that you're not "crimping" a bullet in the case via the chamber mouth when you close a bolt. Don't sweat it, you're fine here.

Kevin Thomas
Lapua USA

 

[jmatters]

I've taken some of my Lapua cases down to 1.990 in my .308 with no ill effects. After seeing the WolfPup cartridge development, I thought that reducing the neck length might contribute to a more consistent bullet exit. Just as we lighten up neck tension by using bushings of a certain diameter, reducing the length of grip the case has on the bullet, without changing the loaded length, should have the same effect. Alas, I'm not a good enough shooter to provide demonstrable results, but I saw no bad effect from it. The bottom line is, whatever trim length you come up with, keep 'em all the same. A shorter length means you don't trim as often. Which reminds me, I still need a Giraud!