7mm bullet length

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by winmagman, Feb 2, 2005.

  1. winmagman

    winmagman Well-Known Member

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    Could some of the 7mm fans please post the length (base to TIP) of the following bullets?
    154 gr Hornady Interbond
    162 gr Hornady SST
    162 gr Hornady A-max
    160 gr Nosler Accubond
    Thanks in advance
    Chris
     
  2. wapiti13

    wapiti13 Well-Known Member

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    Wingman, Don't have all those bullets to measure, but why would you want to? Everyone has a different ogive length, which is what you really neeed to know. You need a bullet to measure in your chamber with your actual throat to see if it will work. Length in your case isn't the big deal some make it out to be within reason, unless you are planning on using a really long heavy bullet in a real small case. You really need a Stoneypoint OAL gauge (or another brand)to really determine anything. Good luck, but watch your bullet choices. You've listed a lot of bullets that are sometimes inconsistent. The Accubond is probably the best out of your list (also made in a 140).
     
  3. winmagman

    winmagman Well-Known Member

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    wapit13
    I'm pondering my next project, a 7mm WSM, and am trying to figure out if I want to put it on a long or short action. I thought I'd throat the barrel to allow shooting heavier bullets seated out a ways.
    With a case length of 2.1" and a bullet length of 1" minus a minimum of .250 for seating to the base of the neck leaves an OAL of 2.850. That crowds the heck out of a short action magazine box and thats if the above bullets are 1" or shorter.

    The 160 Accubond will be my first choice, I just want to be sure I have other options.
    Chris
     
  4. Coyboy

    Coyboy Well-Known Member

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    winmagman, I can only give you the Hor IB. Overall length is 1.380 in. The tapered portion of the boattail makes up aprox. .140 in.
     
  5. 308 nate

    308 nate Well-Known Member

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    winmagman,
    Here is how I built my 7MMWSM.
    I went with a minimum SAME spec 7MMWSM floating pilot reamer and I can touch the lands with a Hornady AMAX and Berger 180 VLD at just under 3" overall cartridge length.This will fit in a savage short action magazine. As far as velocity,You will gain little to nothing by lengthening your throat.If you do want to go with a long throat and load through the magazine,you would be better off with a long action. Last week I did some more load developement and I couldn't be more pleased. Here is my neawest load and velocity out of a 30" Krieger.
    73 grains of realoader #25, 162 AMAX, GM 215M primer, overall case length 2.995, average velocity 3363 fps.,
    3-shot ES measured an unbelievable 4 fps and put two 5 shot groups at 700 yds inside of 3"
    If you try this load in your 7mm wsm start with 70 grains and work your way up. I stopped at 73 grains with no preasure signs. I did see somebodies load up to 75 grains but accuracy and velocity was unsurpassed at the 73 mark.
    anyway here are some overall lenghths of the bullets I have.
    Hornady AMAX. 1.4075
    Berger. 180, 1.514
    Sierra. 175, 1.445
    hope this is of some help,and good luck on the project.
    I'm just happy to see some more 7mm guys out there,because I feel this caliber is under rated. /ubbthreads/images/graemlins/grin.gif
     
  6. wapiti13

    wapiti13 Well-Known Member

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    Winmagman, If you use a long action you may have feeding problems. Use a short action but put a 3" magazine box and a magnum follower. Should allow good feeding and plenty of case capacity. Then pick your bullet and throat accordingly.
     
  7. Richard338

    Richard338 Well-Known Member

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    308 nate
    How fast are you pushing the 180 Bergers? How is the accuracy? I'm building a 7mm myself, but it won't be finished for a while.
     
  8. winmagman

    winmagman Well-Known Member

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    Thanks guys that gives me a ton to think about.

    308 nate
    Did you build on a standard Savage SA reciever or did you use the WSM large shank SA reciever? Also, I'd heard the short neck on the 7wsm was not supposed to be as conducive to accuracy as say the longer neck of the 7saum, aparrently you haven't seen this problem. 3" at 700 yds. is some damn fine shooting.
    Thanks again
    Chris
     
  9. 308 nate

    308 nate Well-Known Member

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    Richard338,
    The 180gr. Berger with 67.5gr. of RL #25 was cronied at 3162 fps. with an ES of 14 fps, accuracy was excellent 5 shots at 700 yards measured 3.25".

    308nate /ubbthreads/images/graemlins/smirk.gif
     
  10. 308 nate

    308 nate Well-Known Member

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    Winmagman,
    I built on the standard .223 single shot SA receiver.But a 3" cartridge length will fit in the SA magazine.(Mine is strictly a bench gun.) I also eliminated the barrel nut.



    This is my feelings on neck length.
    The 7mmwsm neck measures .247.
    The 300 win mag neck measures .264.
    The 6.5-284 neck measures .268.
    The 300 win and the 6.5-284 are both proven 1,000 yd. cartridges. If .020 neck length is the secret I'll eat my hat.In fact the 6mmbr wildcats are taking neck length for more powder capacity and making a heck of a thousand yard cartridge out of it.I have been very impressed by the 7mmwsm cartridge!



    I am not competition bench rest shooter but love to shoot and maybe someday when my kids are grown, I will start shooting competition.But untill then I'll just stick with building acurate long range rifles.
    308nate
     
  11. ColonialBuff

    ColonialBuff Well-Known Member

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    308 Nate thanks. I wanted to look at the 7mm RUM velocities in a Greenhill twist calculation. I really want to get a 7mm RUM on a 700 actions, but was leary after hearing it was tempermental. So, I was trying to get an idea of mussel pressure and twist rates. I am new to long range shooting, but am trying to learn. Thanks for the help.
    /ubbthreads/images/graemlins/laugh.gif
     
  12. fredj338

    fredj338 Member

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    win, I had a sim. dilema when contemplating a .284 on a M700SA. All of the 7mm bullets are loooong, that's why they fly so well. The 160gr NAB is the longest of the bunch. I would look @ the longer box or go to a std. action length.
    160grNAB = 1.405"
    154grHIB = 1.378"
    160grSpeerHC = 1.24"
    160grSpeerGS = 1.07"(this one would work best but lowest BC)
    160grNP = 1.274"
    140grNBT = 1.235" (just to give you an idea)
    Good luck w/ the project.
     
  13. älg

    älg Well-Known Member

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    Here are my 7 MM measures, ACCORDING TO A STARRET DIG. CALIPER:

    BARNES TRIPLE SHOCK 160 1,394
    HORNADY SST 154 1,3495
    A MAX 162 MOLY 1,424
    NOSLER BT 150 1,307
    ACCUBOND 160 1,404
    N PARTITION 160 1,2875
    H. INTERBOND 140 1,288

    I HAVE THE SCIROCCO 150 BUT WERE IN ANOTHER DRAWER AND HAVE NOT MEASURED THEM.