Here is my tip on how to find ideal seating depth.

Discussion in 'Main Message Board' started by jamesdmock, Aug 30, 2017.

  1. Richard Coody

    Richard Coody Gold $$ Contributor

    Feb 19, 2017
    always funny to me to read these post. First thing i will say is whatever works for you.

    this is a good method for the benchrest shooter. bet most that are disagreeing don't shoot consistent groups in the ones and twos.

    with my bench guns i too start with a hard jam and work through load.development. then i back off .005 at a time. i have found secant ogive bullets like the VLD like the jam and the tangent ogive bullets like the MK are more forgiving about seating.depth and like a little jump. the new berger hybrids also like a little jump. now that is .005 off a hard jam so they still are probably touching. anyway after finding the magic seating depth i tweek my load a little.

    for a hunting rifle where i need a mag length cartridge i use the berger test. quick and.dirty. fine tune afterwards. i found a seating depth for a 168 gr. VLD .130 off a hard jam one time. sounds crazy but it works.
    Elwood likes this.
  2. milanuk

    milanuk Team Savage Gold $$ Contributor

    Nov 23, 2004
    @jamesdmock @Tim Singleton I was wondering these same things, if you don't mind...?


  3. Webster


    Aug 29, 2009
    I'm not an expert but I noticed every group shifts the point of impact. Is this as important s group size?
  4. chop house

    chop house Silver $$ Contributor

    Sep 27, 2017

    as has been mentioned, trying to load to the 'touch point' would seem to be, well, a little too touchy. we strive for conditions where the rate of change is minimized, and i can easily visualize a 'keep out zone' there and +/- a couple thou.
    Last edited: Jul 12, 2018
  5. Darrel Martin

    Darrel Martin Gold $$ Contributor

    Jan 12, 2011
    The gunsmith who built my first two custom guns once told me that he thought that nodes would sometimes repeat at about 30 thousandths intervals.
    Some years later , a friend left a well built 308 with me as it shot factory loads well , and I suspected I could really get it to shoot.
    I started 10 off the lands as it was clip fed and a hunting gun so I did not want it jammed. Found an excellent load, but too long for the clip.
    Backed it out to 40 off and it went right back to shooting excellent groups and it allowed the bullets to feed through the magazine.
    Not nearly enough evidence to prove the point, but the load may come back into tune as you back off the lands.
  6. Dusty Stevens

    Dusty Stevens COVFEFE- Thread Derail Crew Gold $$ Contributor

    May 8, 2014
    Im a fan of the running start.

    (Sorry i just couldnt resist)
  7. jsthntn247

    jsthntn247 Silver $$ Contributor

    Mar 9, 2010
    EAE8FD75-665D-4DA9-8756-AA13ACC97CA9.png Here’s my tip, shoot and see

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