case length, OAL & processing for 308

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FNP45

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Last night I went out to the man cave (garage) after the temp dropped down into the mid 90's, cooled off a bit (TX), and started playing with my new stuff for 308 win that has just showed up.

I started by chambering fired cases shot from my rifle (once) and new ammo to see if I could feel a difference, I could not notice any between the once fired and new. The once fired could slide into the chamber with ease with just the fore finger and when closing the bolt I could feel no "crush" or extra resistance when compared to the new factory ammo. I concluded that using my new Redding body die will not be necessary at this stage and that I could just go to neck sizing which is to be done with a Lee Collet die. I have read to full length size on the first go round but I would think that it would only be necessary if the fired case was from another rifle or if chambering was difficult, correct? My goal is to use the Collet die primarily and Redding body die every few firings when needed to insure ease on insertion.

Notes on case length: The case lengths of the once fired were all right around the 2.005" length, which is Lyman's suggested trim length. Since the fired case is expanded and not resized there is no stretch (yet) and no need to trim if I was planning on trimming to Lyman's spec. My plan though for case length is to trim to a more appropriate length for MY chamber which when measured with a Sinclair case length gage tool I came up with 2.054". This was measured three times with a RCBS stainless caliper and by Sinclairs instructions on case prep for when using the tool. They suggest trimming to .024" below your findings which puts me at 2.030".

On COAL i took a case with light neck tension and place a new SMK 175 in the case, just barely and closed the bolt. I did this four times and came up the a COAL of 2.950" for this projectile. My intent is to not load to this COAL and I do not plan on Jamming any of my loads. The rifle is a Rem 700 and I plan on loading to mag length and then working in that range to find the sweet spot on the COAL. This rifle shot quarter size 5 shot group @ 100 yds with Black Hills so I'm not concerned about the jump.

My questions are, what do you think?
Does everything seem on the up?
Does a trim length of 2.030" sound good, longer, shorter, suggested max length before trimming? my thoughts where no longer that 2.040"
Also on COAL I'm wanting to go around mag length or shorter, but what would be a minimum, not that I want to go short, Lyamn's shows a 2.800".

Thanks

I have loaded around 2k of 9 & 45 but I think rifle loading is going to be more rewarding :D
 
I could not notice any between the once fired and new.

If your once-fired brass is from the same rifle as you are sizing it for, then neck sizing works well, and yes, every so often it is recommended that you FL size them to bring them fully back into spec. as they will eventually become a bit more difficult to chamber after some number of firings...rule of thumb is about 5 firings to FL size if you are neck sizing. You may need to FL size more or less often.

Does a trim length of 2.030" sound good, longer, shorter, suggested max length before trimming? my thoughts where no longer that 2.040"

I am sure the 2.030 and 2.040 trim length is a decimal error...did you mean trim to 2.003 or 2.004? Either of those numbers sound fine, and I have loaded cases that I accidentally trimmed down around 2 inches or a couple of thousandths less, and they shot fine, though I would not use them in a match.

Also on COAL I'm wanting to go around mag length or shorter, but what would be a minimum, not that I want to go short, Lyman's shows a 2.800".

2.800 is the SAAMI spec. for COAL for 308 Win. How short or long you load them is dependent on the projectile and powder charge weight/volume, the magazine as you have already mentioned, and what your rifle prefers. I also have Rem 700s in 308 Win and 243 Win, and I find they both like something very close to the SAAMI spec. However, your rifle may prefer something different. As to how short is short, that depends on how much powder you are putting into your brass case as well as the length of the projectile and what your rifle likes. Some bullets are loaded as short as 2.6 or 2.7ish (Lyman 49th ed.), but some of these are the lighter weight bullets. So if you are loading SMK 175s at 2.75 and they shoot well, then that's fine as long as you aren't having any undesired powder compression or over-pressure issues.

I would, at first, stick close to the SAAMI spec. and then venture longer/shorter.

I have loaded around 2k of 9 & 45 but I think rifle loading is going to be more rewarding

I do not load pistol, but I can tell you that I enjoy loading rifle rounds very, very much!
 
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