Muzzle velocity VS Muzzle Energy

Discussion in 'The Powder Keg' started by nc.hunter, May 14, 2008.

  1. nc.hunter

    nc.hunter Guest

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    Hey guys, I called my local walmart, and they have a savage bolt action .17 HMR for 177.99, but they also have a marlin bolt action .22 magnum for 197.99. I am having trouble picking the one to buy. So I have boiled it down to this, would you rather have more velocity 2550 with the .17HMR with 245 lbs. of ME. or have a velocity of 2200 but have ME of 322 lbs.? You decide, all feedback appreciated.
     
  2. Personally I use MV strictly for load building where I can run them over the chronograph to calculate pressure.

    If you can find down range ballistic data, I would go by that. Which gives the best combination of velocity and energy at the ranges you would typically use it at?
     

  3. Since I own several rifles in both of the calibers I would go with the .17 with the faster velocity as it will give you a flatter shooting weapon with a better point blank zero. The .17 has a lighter bullet but what it will give you in speed and distance with great accuracy is worth the energy trade off in a small caliber. If the question was about a centerfire hunting cartridge then the thinking would be different for me taking into consideration what I was intending to do with it and the rifle twist rate.
     
  4. Ron AKA

    Ron AKA Guest

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    Have a look at the article at the link below. May help you decide. Energy at the target distance is what counts. The .17 HMR loses energy faster. Personally I would go with a .22 LR, and if you need more power than the CCI Velocitor, then step up to a centerfire. The .22 LR will be much cheaper to shoot than the HMR or .22 Mag.

    http://www.chuckhawks.com/compared_17HMR_22WMR.htm

    Ron
     
    Last edited: May 14, 2008
  5. neophyte

    neophyte Wonderment :) Forum Contributor

    What cha got in mind

    nc. hunter: Sir; what cha got in mind?

    If you were looking to target at distances and maybe do a little ground hog or varminting; the .17hmr will cover much more territory.

    Longer range flatter shooting and a "whack" at the other end.
    Now given the .22 isn't too shabby; it'll not do what the .17hmr; as far as inherent accuracy nor "whack" at 100yds by comparison.

    Me? .17hmr knowing about what it'll cost to shoot.
    Compare the price to your ammunition and see if that points you differently.

    Follow up with more good questions and your thinking. Thanks
     

  6. Ron, the site you ref shows the .17 losing much less energy than the .22 mag at all ranges, not more. Or am I missing something?

    From the site :

    " The .22 WMR starts with about a 75 ft. lb. advantage in kinetic energy at the muzzle. At 50 yards the 40 grain .22 bullet is carrying about 45 more ft. lbs., and at 100 yards the 40 grain .22 bullet still has a 25 ft. lb. advantage over the .17 bullets. At 150 yards the .17 HMR has an energy advantage of about 20 ft. lbs. over the 30 grain .22 bullet, and we have no figures for the 40 grain bullet beyond 100 yards"


    It appears that the .17 retains energy better than the .22 mag as distance increases.
     
    Last edited: May 14, 2008
  7. rfc357

    rfc357 Guest

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    Energy is a very misunderstood topic. I don't see much to choose between the .17 and the .22 WMR. The .17 should be OK for the smaller critters. If I were shooting NY woodchucks, I would go with the .22 WMR for the heavier bullet.

    Neither is much good beyond 125-150 yards, except on the smallest of critters. You can hit 'em, but you may not anchor them.
     
    Last edited: May 14, 2008
  8. Ron AKA

    Ron AKA Guest

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    "we have no figures for the 40 grain bullet beyond 100 yards"

    The 40 grain WMR has more energy at all distances. The missing 150 yard energy number is 124 ft lbs. I'm surprised that someone writing for Chuck Hawks does not know how to calculate the velocity and energy at any range once they know two ranges.

    Ron
     
  9. sell33

    sell33 G&G Enthusiast

    I have a 22 mag that i am confident in out to about 150. Either will do work on small varmints out to around that, that is stretching a 22 mag though. What do you plan on doing with this rifle? Also i have heard if you plan on eating something the 17 hmr does a lot more meat damage, of course head shots with either would work on squirrels, rabbits. etc.
     
  10. samuel

    samuel G&G Newbie

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    Muzzle velocity=muzzle energy. sam.
     
  11. SwedeSteve

    SwedeSteve Freedom Zealot Forum Contributor

  12. .22 mag all the way!

    +1 +1+1
     
    Last edited: May 15, 2008
  13. Ron AKA

    Ron AKA Guest

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    Yes, if the bullet weights are the same and velocity is the same then muzzle energy is the same. However if the velocity is the same but bullet weight is different then the energy will be different. A formula to calculate energy can be found here, along with a calculator to do it.

    http://www.arld1.com/images/swfs/kineticenergy.swf

    Ron
     
  14. rfc357

    rfc357 Guest

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    Muzzle velocity does not equal muzzle energy. Energy equals 1/2 times mass times velocity squared. Don't make hand out some Fs in physics!
     
  15. I was going to point that out also but I was too lazy to look up the formula and I just didn't have the heart to disagree with Sam. I think he was just kidding, a person of his experience and knowledge would know better than to say that muzzle velocity equals muzzle energy.
     
    Last edited: May 16, 2008
  16. samuel

    samuel G&G Newbie

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    That proves that you can have energy without velocity?I hardly meant the #,s were going to be identical. sam.

    It depends upon what the meaning of the word 'is' is.Or in this case 'equal'.I should have written builds,creates,manufactures,.Oh well most will understand anyway.Thanks for keeping me straight. sam.
     
    Last edited: May 17, 2008
  17. How about this Sam more muzzle velocity equals more muzzle energy.
    Now how about a momentum formula. momentum = mass * velocity
    Velocity is more important at the muzzle but momentum is more important at the point of contact.Hows that for muddying the water. heh heh heh
     
    Last edited: May 17, 2008
  18. rfc357

    rfc357 Guest

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    Sam,

    Absolutely not. If the velocity is zero, the kinetic energy is zero.
     
  19. Ron AKA

    Ron AKA Guest

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    Actually I would not agree that momentum is an important factor. It is if you have tug boats and things bumping into each other and you want to figure out velocity of each after they bump in an elastic manner. Energy is energy. It is the capability to do damage, and it is the bullet's job to fulfill that capability. This is not an elastic collision, and the momentum is not useful to predict anything.

    For the same bullet weight if you double the velocity the energy increases by four times, due to the fact that energy depends on velocity squared.

    Ron
     
  20. samuel

    samuel G&G Newbie

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    You have proven your point I admit that you are the one to post all info on this forum and I will be silent from now on because we dont want people to believe that a bullet must be in motion to have any energy.I feel a great lack of energy so I will quit posting on here and become motionless and build up some energy.I would like to know how many understood you two and your formulas,or even cared. sam.