[mnbull]

Hi All,
I am new to reloading and am a little confused on case length. The manuals say the 'trim to' length is 2.484". I have a bunch of once fired brass out of my Remington 700 .30-06 (using Remington and Hornady Factory loads). I figured since i have only fired them once, I wouldnt need to trim. However, these cases are measuring at 2.594". So i bought a Lyman EZ Trim and used the .30-06 length gage and it only shaved it down to 2.591". What gives?
I even measured an unfired rounds case and it measures 2.582". Can anyone help a new guy out and shed some light on this. Do I need to trim to this? Obviously I would think so since its in the manual, but I never thought I'd need to trim that much brass off.
Also, any tips on finding the correct seating depth for your rifle would be appreciated, (step by step would be very helpful). I am using Nosler BT 180 grain bullets.
Thank you for any help, much appreciated!
MNBull

 

[Alpo]

Sounds to me like your measuring tool is lying. Either it is off or you are reading it incorrectly.

 

[mnbull]

Wow, do I feel like an idiot. Just inspected the caliper more and there was a small metal shaving in the groove where it slides. In my haste, i wanted to hurry the process and did not check caliper well enough. I've been zeroing it off this..... Lesson learned. Ahhh, the infinite wisdom of a newbie!!.....

 

[Alpo]

Well, at least you asked before you cut all your brass 1/8 inch too short.

 

[jim brady]

That was another good call, Alpo.

I have gotten into the habit of wipeing down my tools - especially measuring tools - with a clean cloth whenever I get them out to use. Most folks would be surprised as to how nuch dust and lint will gather on those things. I think mnbull can testify how far off those readings can be with a tool that is not clean.

As far as the seating debth, a great place to start is with the seating debth given in your manual. If for some reason your manual doesn't specify a certain seat-to-length for a given bullet wieght, I'd start by seating your bullets under maximum overall length. You can experiment from there with shorter or longer seating debth and see if you gain tighter shot groups. My Lyman manual suggets 3.280 for the 180 grain jacketed hpbt and 3.275 for the Barnes 'X' 180 grain bullet.

Some guys like to seat their bullets way out so the bullet is just short of touching the rifleing. Benchrest shooters do it all the time. I don't do that because 1.) your ammo is then pretty much limited to use in your rifle only, and 2.) unless your rifle is a single shot, you are risking a jam in the mag from too long of a loaded round. Best to keep them under the 'Maximum Over All Length'.

Sure as the sun will rise the next morning, somebody will scorn me for adviseing you to do this, and I've lost track of the numbers of my critics, but it is what I do and it works for me. I load for six different 30-06 rifles.

 

[mnbull]

Thank you JimBrady for the sound advice. I will probably try both methods and settle somewhere in between, as long as I still get good groups.
Thanks again

 

[LDBennett]

mnbull:

Remember you MUST size the cases BEFORE you trim. The length of the case body changes with sizing. The case length measurement is only meaningful after sizing.

LDBennett

 

[mnbull]

Thanks guys,
I got it all figured out. Loaded some shells in different charges with superformance (54, 57 and 59 grains, all i could find right now) and am going to the range today...I checked my bullet seating depth in my rifle and it was 3.464, after six checks. I loaded my rounds at 3.444 to start. I may take jimbrady advice above though, depending on what happens....