Muzzle energy ?

Discussion in 'General Rifle Discussion' started by Green Lantern, Jan 13, 2020.

  1. Maineiak

    Maineiak Member

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    I don't know about that. I don't think semi-autos recoil less than a bolt gun of the same weight. For one thing, an auto loader has the reciprocating mass after the initial recoil from the round going off. So, unless I am wrong, you have the recoil from the round, and split second after you have the reciprocating mass recoil.

    some auto-loaders have the barrel come back and cycle the round, I think they have the most recoil
     
  2. primer1

    primer1 Well-Known Member Supporter

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    ^^^^^ there is definitely less felt recoil in a semi automatic, all other factors being the same.
     
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  3. Maineiak

    Maineiak Member

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    how do you figure that?
    the bullet has all but left the barrel before the bolt opens up, and it has the same force.
     
  4. primer1

    primer1 Well-Known Member Supporter

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    I figure I'm not a physics professor. The action and recoil spring/gas system slows down the recoil of the firearm, or spreads out the recoil over a longer period of time.
     
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  5. Maineiak

    Maineiak Member

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    You could be right, I used to think that as well.
    Personally I don't really know, but it seems to me that my BAR kicks about the same as a bolt gun.
     
  6. tac foley

    tac foley Well-Known Member

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    With a rifle, it's all down to the way the gun is held.

    With a handgun, it's all down to the way the gun is held.

    I've seen ten-year-olds shooting my .45-70 High Wall with 500gr lead loads and giggling. I've seen grown men shooting the same load and getting the almighty snot kicked out of them.
     
  7. JimRau

    JimRau Well-Known Member Supporter

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    A lot of good info here, but few people realize a BIG factor in 'felt' recoil is the 'time' factor. The higher the 'speed' of the recoil the more 'energy' is delivered in a shorter time. The difference in a 'punch' and a 'push'.;) Most don't realize the real sharp reboil is delivered by the mass of the hot gas (propellant) leaving the muzzle, not the bullet/load weight. That is why a GOOD muzzle brake lessens felt recoil. Thus the difference in the recoil of a shotgun verses the recoil of the rifle.:)
     
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  8. RJF22553

    RJF22553 Well-Known Member

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    Jim, good analogy. Much like steel versus hard rubber versus pneumatic tires. Or shock absorbers. Or a rubber handle on a ball-paean hammer. Or a helmet versus a ball-cap.

    All handle the same force; all distribute it over time and space.
     
  9. Green Lantern

    Green Lantern Active Member

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    Adding ...... Or a spring loaded stock. Like the Hi-point 995. Or Phoenix industries spring loaded stock, like on my 12ga
     
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  10. Oldoutlaw

    Oldoutlaw Well-Known Member Supporter

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    Don't you have a 338 Lapua?
     
  11. Maineiak

    Maineiak Member

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    That rifle belongs to my friend, I was holding onto it for him. The 338 Lapua does have some recoil.
     
  12. Green Lantern

    Green Lantern Active Member

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    From a recoil website.
    12 gauge, 2.75" (1-1/4 oz. at 1330) 32.0 lbs
    .338 Win. Mag. (200 gr. at 2950) 32.8 lbs
     
  13. Maineiak

    Maineiak Member

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    I was shooting 300 gr @ 2723fps 4938 ft/lb
     
  14. Oldoutlaw

    Oldoutlaw Well-Known Member Supporter

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    Until the shock wave bounced off the front of your truck window. :D
     
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  15. Green Lantern

    Green Lantern Active Member

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    Nearly 5000 lbs of recoil might crush some bones.
     
  16. Pasquanel

    Pasquanel Proud to be an American Supporter

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    A true statement for sure, my buddy bought a .378 Weatherby mag from an estate sale many years ago. We took it to range and flipped a coin to see who would go first.
    I won so I loaded 3 rounds in the magazine and shot standing at 50 yards. The first shot was right on the second hit the very edge of the paper and I'm not sure if the third round has hit the ground yet! Yikes!! that's some serious recoil, I know gun writers will say "it's a bit stout"! No it kicks like an angry mule and I'm thankful I did not attempt to shoot it prone!
    My buddy said "how was it?" and of course I answered " not that bad" he fired one shot and that was enough he wanted to sell it to me for what he payed! In retrospect I should have bought it because it was worth way more than he paid for it.
     
  17. freefall

    freefall Well-Known Member

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    A lot of felt recoil is how much you weigh and how you're put together. A big chesty guy gets hit harder than a lighter guy, because the lighter guy moves more.
    Just like Pasquanel shooting it standing and not prone.
     
  18. Green Lantern

    Green Lantern Active Member

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    This will help me then, because I'm losing weight. Headed for 100 lb goal.
     
  19. Wambli

    Wambli Well-Known Member

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    3 main factors to consider:

    Mathematical recoil is what the math of physics tell you and those are the numbers you are reading show. They are theoretical and can only be used if EVERYTHING else is equal. For example if you shoot the EXACT SAME MODEL of a Kimber 1911 in .45 and the same gun in 9mm, of course the 9mm will be softer recoiling than the .45.

    Perceived (felt) recoil has to do with the caliber, chambering (two different things), design of the gun, stock, grips, shooter stance, shooter size, shooting position and the HIGHLY subjective shooter perception of recoil. There is NO way to figure that one out except to say that given the above case (same gun, same shooter, same shooting circumstances etc) the heavier bullet will have more felt recoil.

    Shooter managed recoil. Some folks are just adept at managing recoil through training and/or natural abilities (yes there is such a thing) and have gone past the stage where recoil is a meaningful factor in their shooting. If I just hand my daughter (all 5’3” of her) multiple guns to shoot she can’t really tell you there is much difference between firing one of my .45 1911s and my 10mm equivalent gun, as an example. When she shoots she has been trained to manage all recoil and shoot for effect, so if you ask her which gun “kicked harder” she will just give you a blank stare because it means nothing to her so her brain just ignores it unless she is specifically is trying to notice the difference.

    There is a video out there of Sheriff Jim Wilson dumping an entire cylinder out of a short barreled S&W 500 accurately at a target as fast as he could pull the trigger, and there is almost no muzzle flip. THAT is recoil management at its finest.
     
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  20. SGWGunsmith

    SGWGunsmith Well-Known Member Supporter

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    You forgot one very important factor. "A LOT depends on which side of your mouth your tongue sticks out of."
    If you're a right hand shooter, it's the left side and if you're a left hand shooter, the right side.
    I've sighted in some of the Weatherby cartridges for customers after mounting scopes, like the .340 Weatherby and the .378 Weatherby. Even when using a PAST shoulder padded vest, I still swallowed several tooth fillings that came loose. Those bigass bottle-neck cases with small diameter necks are really brutal to shoot on a regular basis. Muzzle breaks, sorbothane recoil pads and mercury recoil reducers installed into the buttstock are friends for all of us. Anyone who claims they like the recoil from those guns, should be confined to a room with rubber walls.
    I've also sighted in a couple of .458 Winchester magnums, including one Ruger Number I, and those straight wall cases are much less likely to cause blood clots, IME.
     
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