Ft.lbs - How Much Is Enough?

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by CaptnC, Jul 16, 2018.

  1. CaptnC

    CaptnC Well-Known Member

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    Extended range is extended range whether talking about a 22 LR or 33 Nosler, not every caiber is the same. And inside ever caliber the actual chambering will make a big difference!

    How much energy do like to see on impact at max range for that chambering?

    Personally I set mine at 1,000 ft lbs. What ever chambering I'm shooting must have near that for me to take the shot.

    The 6.5 Grendel is the cartridge at the center of the discussion. Most of the guys are shooting gas guns (myself included) so that takes a little more away from the down range effectiveness of those bullets.

    I've recently been engaged in several discussions where guys are taking shot where they only have 500 ft lbs of energy on impact.

    IMO - that is not enough!

    What is your take on bullet energy at Long ranges?
     
  2. Edd

    Edd Well-Known Member

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    The universal standard is 1800 fps velocity and 1100 ft lbs at the target.
     
  3. elkaholic

    elkaholic Well-Known Member

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    I've never been a big believer in ft/lbs as the determining factor except it needs to be enough to open the bullet reliably. This is especially true at long range where if you have enough velocity/energy to cause the bullet to perform properly, you are likely fine. Tissue damage by tearing And leaving a sizeable hole is what kills most animals. (Hemorrhage) in other words 2000 lbs of energy penciling through is not near as good as 700 tearing a hole. Archery is a prime example.
     
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  4. Idaho Lefty

    Idaho Lefty Well-Known Member

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    YUP,.. THIS ^^^^^ Nosler shows, the lowest "impact" velocities for EXPANSION, on their AccuBonds, I like that ! The .270 cal. 140 grain, minimal performance Velocity is 1,800 FPS OR,.. about, 800 Yards, in my .270 WSM ! That's farther than, i want to shoot !
     
    Last edited: Jul 16, 2018
  5. HARPERC

    HARPERC Well-Known Member

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    The 1800 fps terminal velocitis more important to me generally. Most big game Bullets will show some expansion at that point.
    Energy figures are all but meaningless to me.
    Adjustments in caliber and weight for game size will produce more "energy", but its the increase in wound size, causing greater loss of vital tissue I'm after.
    Specific to the Grendel are there more "varmint" oriented bullets that perform at lower velocities? I know the "Z-MAX" in the 7.62x39 really opened readily.
     
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  6. Idaho Lefty

    Idaho Lefty Well-Known Member

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    I agree with HARPERC,.. Your Gun's Maximum "range", is at about, the range when your Bullet is hitting, the 1,800 FPS MINIMUM velocity "area", to get,.. some EXPANSION !
    Elkoholic ,.. "Nailed it", too !
     
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  7. Idaho Lefty

    Idaho Lefty Well-Known Member

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    In 2016, my son killed a 5X5 Elk and a Shiras Bull Moose with, 505 Grain Arrows launched at 285 FPS, using a 67 pound Bow ! Both animals were shot at 35-45 yards and went 25-40 yards, to DIE quickly ! Complete pass thru both times ( Lungs ) very SHARP Exodus, BH's.
     
  8. CaptnC

    CaptnC Well-Known Member

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    6.5 Grendel velocity is down to 1475fps with 540ft-lbs...at 500yds. Just not enough IMO.

    I've bowhunted since the late 70's...longbow, recurves and of course compound bows. I lost track how many deer and hogs have fallen to my arrow!

    But a bullet kills differently than the broadhead. There are no hydraulic shock in a arrow like in bullets. There is a lot of trauma from the energy dump when a bullet expands. You don't get that from an arrow...
     
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  9. tim_w

    tim_w Well-Known Member

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    In the end I am with Rich on this. You really have to know how is a given bullet going to expand and how far and straight its going to track once it hits the flesh. Its also game dependent.

    Deer, Moose, Elk, Mullie or Browns, Blacks, Hog, Amer Buffalo, Cape Buf, Hippo, etc

    Also now that we have Mono bullets that can be designed to open and very low vel etc it add variables yet again.

    But lets just talk standard jacketed lead core

    A 6.5 bullet full expands say at 2000 fos impact vel but a .375 bullet with just metaplate deformation to match its caliber diameter would give you the same basic frontal area for the per damage path and the weight would easily take care of penetration depth. The only thing where this changes is when vel is high enough it creates the secondary damage from the temp wound expansion actually creating permanent damage . But most all I see is impact vel below 2K so that can not be counted on.,

    Sd can cover caliber and weight for the most part but still you need IMO caliber size for damage path. Vel for expansion limits and of course range. Energy is helpful but then once a bullet is creating an exit hole its not really offering much only that limit is reached for a given game animal.

    Unless you give a healthy over compensation I do not think you can really rely on any single number to get you there. Too many variables.
     
    Last edited: Jul 16, 2018
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  10. elkaholic

    elkaholic Well-Known Member

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    True to a point but you don't get much hyrauluc shock effect at long range terminal velocity or shorter range when mv is low to begin with.
    If you used a bullet like the ELDM, you would get expansion at 1475.
     
    Last edited: Jul 16, 2018
  11. RockyMtnMT

    RockyMtnMT Official LRH Sponsor

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    energy is a good number for comparing cartridges around the camp fire. Bullet construction and design with impact vel are much more meaningful. We need to teara large enough hole to cause fast bleeding. Sectional density plays a role as higher sectional density initiates bullet deformation more easily. Bullets should deform to a predictable form regardless of impact vel, high or low.

    Steve
     
  12. SidecarFlip

    SidecarFlip Well-Known Member

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    Only 'gas gun' I own is a WW 2 Nazi Paratroopers flamethrower. You can BBQ your quarry at 100 feet.
     
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  13. CaptnC

    CaptnC Well-Known Member

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    6.5 Grendel velocity is down to 1475fps with 540ft-lbs...at 500yds. Just not enough IMO.

    I've bowhunted since the late 70's...longbow, recurves and of course compound bows. I lost track how many deer and hogs have fallen to my arrow!

    But a bullet kills differently than the broadhead. There are no hydraulic shock in a arrow like in bullets
     
  14. MagnumManiac

    MagnumManiac Well-Known Member

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    To date, I have used the 129gr ABLR at LOWER velocities than 1300fps on game.... they all DIED. 2 of the bullets recovered are expanded more than expected and 1 is right where I expected expansion to be. So far, according to my Ballistic AE app, the slowest impact velocity was 800fps, the bullet expanded a 1/4” below where the tip would have stopped in the cavity, ideal expansion for such slow speed. The bullets were also facing the way they entered, a bonus in my book. I have not used the 142gr ABLR past it’s recommended velocity as yet, as I am still fine tuning the load for it. Both are fired out of my 264WM 1:8” twist 30” barrel at amazing velocities that I will keep to myself.

    I don’t advocate doing this, but I had huge problems with Berger bullets NOT expanding at all and tumbling through game at shorter ranges than the above examples.
    Please do not ask me the ranges, as I am NOT willing to post them here or elsewhere. I asked Berger about this problem and I got my answer.

    I am not bad mouthing Berger bullets, I bet if I push the range further with the Noslers I will get the same results.

    I tried a similar test with my 6.5x47 but was bamboozled by wind on every occasion and only managed a 1200fps hit with the 129ABLR, it looked no different to a higher velocity hit and had expected expansion.

    I’m still trying to get my hands on some 30 cal ABLR’s, but there are none in stock here at all.
    Oh well, guess I’ll have to wait to test these too.

    Cheers.
    :)
     
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