? on volosity spread.

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by billn17, Aug 3, 2013.

  1. billn17

    billn17 Well-Known Member

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    Ok finally purchased a chronograph and got my first readings. I'm shooting 300 wm, 190 smks, with 84.2 gr of wc872 going down a 27 1/2" pipe with 1/10 twist. No crimp

    Avg. 2879 fps
    spread. +/- 15.5 fps

    my question is, is my spread good or bad.
     
  2. 375fan

    375fan Well-Known Member

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    Everyone wants single digit spreads, but 15 ain't bad. What's your groups( especially vertical dispersion) like at longer ranges? Say 300 yards.
     

  3. billn17

    billn17 Well-Known Member

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    Re: ? on velocity spread.

    Well at 100 yrds im getting sub moa. With this load the one time 3 shot group at 300 yrds was 1 1/4" group. Im still working the load. I'd like to get 2950 out the barrel.
     
    Last edited: Aug 3, 2013
  4. Lefty7mmstw

    Lefty7mmstw Well-Known Member

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    that's (2879) already good speed for a 300 win,190, and wc872. I can't get much past 3K with a 300 win with powder that CAN hit peak pressure in a 26" tube; I'd bet you are at highly compressed charges already. With wc872 in my 30 rum with a 190 hornady I will hit 3200 fps before I'm out of headroom.
     
  5. billn17

    billn17 Well-Known Member

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    Yep its filled to the bottom of the neck. However no signs of pressure.
     
  6. johnnyk

    johnnyk Well-Known Member

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    Bill,
    Try some H1000 if you can. I tested 79.0-80.5gn and at 80.5gn I'm averaging 3145fps with groups at 100yds running in the low .4's. SD ran 13.63. Ths is using the CCI 250 primer.
    The group I shot at 79.0gns printed a .142" group, averaged 3078fps and the ES was 7.83, SD 4.12.
    This is from a stock Savage 112BVSS 26" barrel. JohnnyK.
     
  7. billn17

    billn17 Well-Known Member

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    I do have some h1000 and have used it. It does print good # but at $155 for an 8lb vs wc872 @ $46 / 8lb its hard to switch back.

    But may have to, to get my velocity up for the mile shot though.
     
  8. MontanaRifleman

    MontanaRifleman Well-Known Member

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    Unless you bought an Oehler you do not have a precise instrument. Your spread could be 5 fps or 50 fps. Buy or borrow another identical Chrono and put them back to back and check out the resuts. It will be an eye opener. Even Oehler's are not perfect.
     
  9. Lefty7mmstw

    Lefty7mmstw Well-Known Member

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    +1

    I don't trust any of the single clock setups much, including my CED. I trust my Oehler a lot more; my dad has it at his place though so it's a problem to get it to the range at times. The single clockers are good for a guess, but may easily be 100 fps off either way. I'd bet closer to 3 Kfps with and h1000 as that's all I've been able to muster; I have seen one ruger #1 in 300 win though that'ld do 3Kfps even with 200 speer pills and retumbo. Hardest hitting rifle I've seen shooting prarie dogs.:D
     
  10. billn17

    billn17 Well-Known Member

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    Crap! I didnt know that. I do know that I get 8.25" @ 300 yrds. Im trying for 2950 to reach those long ranges.