Seating depth or charge weight ?

Discussion in 'Reloading' started by njshooter, Oct 23, 2012.


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  1. njshooter

    njshooter Active Member

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    I'm trying to get an accuarate load in my Weatherby Vaguard 30-06. Should I start with seating depth first, then work up to max load or max load then seating depth.

    I've shot Bergers (168 gr.) and Accubonds(165 gr.) with H4350 from touching the lands to .120 off. The best I group was with Bergers (1.5") @ 150 yrds. .100 off the lands. Accubonds best was 2.5" @150yrds.

    I bought a box of Hornady Match 168 AMAX. (M1 Garand) These shot from clover leafing to .75" @ 150 yrds. I've read that Amax bullets are to fragile for hunting so I want a better hunting bullet. I'm guessing they are using IMR 4064 because it contained only 49.6 grains of powder and they are seated .115 off the lands.

    What am I doing wrong that I can't get the same or better accuracy with my hand loads. I'm also letting the barrel cool for about 3 mins. between shots.:rolleyes:
     
  2. Joe King

    Joe King Well-Known Member

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    Seating depth first, then find what powder charge it likes, (may not be max), then find which primer it likes.

    If it still won't shoot you may want to check midway to see if they have any Classic hunters for your rifle, I've found them to be really easy to work up a load.
     
  3. JackinSD

    JackinSD Well-Known Member

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    You can get just about as many answers to your question as there are responses. Personally, I don't worry about what the max load will be. I try to find the accurate charge and then adjust seating. The other way around may work just as well. Never tried it, so I'm not saying mine is right.

    My opinion, just mine, is that the AMAX bullets are very good bullets for hunting. I only have experience with them in a couple of antelope. They did very very well.

    I read many many opinions of the AMAX for hunting. Opinions on both sides of the aisle. Enough that I had to try them for myself. They were my most accurate bullet at any given distance. So, I went for it.

    They were shot out of a .243 at 435 yards and 633 yards. Both heart/lung shots. Nothing but jello on the inside, small hole in and a little larger hole going out.
     
  4. MSLRHunter

    MSLRHunter Well-Known Member

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    I do the opposite of the other posters. I work up to my max powder charge then back off until I have no pressure signs, usually about 1-1.5 gr. These are loaded to the max length that will fit in my magazine. Then, if accuracy is not what I expect I begin to decrease seating depth until I find the sweet spot.
     
  5. green 788

    green 788 Well-Known Member

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    The powder charge is your coarse adjustment, then the seating depth should be altered to fine tune the load.
     
    Code4 and dwinmeade like this.
  6. Mikecr

    Mikecr Well-Known Member

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    I disagree about powder being coarse.
    Seating can affect grouping by 2x-3x powder effects. Primer/primer striking, if not right, is also bigger than powder.

    So I agree with Joe King.
    I find seating first, using method similar to Berger's recommended.
    Powder is my FINE adjustment, after shooting a ladder.
     
  7. green 788

    green 788 Well-Known Member

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    when your powder charge is not an OCW charge, then yes, seating will affect your group size severely.

    For optimal charge weight loads, it's far less important (think about how well factory match loads shoot with an arbitrary seating depth)...

    Once the powder charge is optimized (by methods I describe on my main OCW site), you can then take advantage of the fine tuning that seating depth adjustments allow.

    So in short... if you're finding that a small seating depth change ruins your group, you're using a non-optimal powder charge and, as I call it "walking the tightrope to accuracy."

    The same thing applies to primers... some folks have primer brand sensitive loads, and that too is indicative of a non-optimal powder charge.

    Dan
     
  8. Speck

    Speck Well-Known Member

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    Feb 11, 2012
    I start with a low charge, find the seating depth it likes to run at then up the charge till i find the sweet spot. Either way works. As for primers, i've had the best luck with CCI BR primers.
     
  9. Pete Callamaras

    Pete Callamaras Well-Known Member

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    . When I first started, I bought a few different boxes of factory ammo, and found that my rifle liked Hornady 168g A-Max black. So I used that as a starting point. I matched the velocity, then worked on seating depth with the A-Max. then branched out from there as I started reloading.
     
  10. just country

    just country Well-Known Member

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    morning, magazines-clips CAN hinder finding the proper seating
    depth for accuracy. there r vast amounts of reloading data on the
    30-06. refer to search mode on this site for a start.
    justme gbot tum
     
  11. aushunter1

    aushunter1 Well-Known Member

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    Nov 16, 2012
    For the last 15 years of my reloading experience I have always done it this way without to much failure-
    I start all my LD at 10 thou off the lands.
    I go through the recommended range for the specific powder at either .3gr or .5 gr increments depending on that range, if its a 3.5 gr range then I do .3, if it 4 to 5 gr then I do .5gr.
    This is shooting 5 rounds per group.

    Once I find a result worth exploring which is usually already at around MOA or under I then start to adjust my seating depth which I then go to 5 thou, 15 thou & 20 thou, again shooting 5 per change to seating depth.

    Then once I have found the best result from that depending on how it works out I will then try to tweak it by doing .1gr & .2gr powder charge increment changes either side of the best charge amount @ that CBTO depth both on the upper side & the lower side.

    Don't forget that this all comes out of proper case preparation!

    *Flash hole deburring
    *Primer pocket uniforming
    *Case annealing for good neck tension if not using new cases or multiple fires cases
    *All the other usual stuff like debur & chamfer, trim to length etc
    *Using good quality die & press

    If I have failed by this stage & I really want to use this projectile then I will change powder & go through the same procedure.

    Everything has to be consistent in what we do otherwise the results are flawed!
     
  12. Plinker147

    Plinker147 Well-Known Member

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    I find the fps range/ impact clusters I’m looking for using ladders, then load groups around that. I start with .020 off lands( depending on knowledge of the bullet selected) then adjust seating depth from there. I have always viewed powder as coarse and seating depth as fine adjustments. Seems I’m backwards from most on here.
     
    Last edited: Oct 4, 2019
  13. YZ-80

    YZ-80 Well-Known Member

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    Feb 20, 2019
    For me, for just about everything I reload for, “closer” (but not too close) is better. Every pet load I’ve developed has been seated between .015” to .020” off the lands and they all shoot well. I chase the throats accordingly. I also pay close attention to neck tension and concentricity. This gives me between .25 to .75 MOA out of every rifle I own. I think the powder choice is more critical. So, at the risk of oversimplification on the topic, I’ll say seating depth has been a “set it and forget it” proposition for me. At the same time, I’m sure there are gains to be made by manipulating seating depth for you guys that are reaching way out.
     
  14. K9TXS

    K9TXS Member

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    Nov 4, 2014
    I too do the powder charge first and then come off the lands. Below are my examples. I used the COAL for these particular loads. Normally I use the datum line measurement, but had a slight issue so I used the COAL this time.

    Cooper 20 Vartarg

    [​IMG]

    [​IMG]