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I have been doing testing and more testing of factory 444 ammo this summer. It's gonna be a something else, when I'm done, but along the way, I've thrown in some other testing on the side. This past weekend, while testing, I threw a water quenched 237gr Sage Country and a 187gr Chino Valley into the jugs in the velocity range of 1600-1650fps.
For the first time I can see where I am producing comparative data with cast bullets and jacketed bullets with impact velocities in the 1600 fps or 200 yard velocity range. As a broad generalization, it seems that regardless of weight and velocity of the bullet you are pushing in your 444, if your starting velocity is near max for that bullet weight, then your velocity is going to be in the 1600fps range at 200 yards. 1500fps range for bullets around 400gr and up.
I also notice that differing terminal performance become more pronounced at the 1600 fps range.
With the two tests with my prototype cast bullets, I have been able to produce definitive visual evidence of the differences of terminal performance at those impact velocities. Even more, specifically demonstrating the huge disparity in terminal performance that as attributed directly to meplat size at those impact velocities. I and others have discussed the issue of meplat size, but I am getting to the point that I can clearly demonstrate it without dispute.
First, I have to wind up my factory ammo testing that has at least one more round of tests before it's complete. I had hoped to have that completed by now, but I have added much more to it and extended the amount of time that it will take to complete those tests and put it all together. Once that is done, I'll switch my focus to cast bullets where meplat size will be one of the primary focuses. A few different forum members have sent me some of their cast bullets to add a lot of variety and interests to that round of testing.
Anyways, I was just reviewing footage of tests in the 1600fps range and saw such a huge disparity revealed in regards to meplat size and I thought I'd share that with you'all.
 

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SIZE does matter :driver: add velocity and size even gets bigger :biggrin:

I bet no one sent you a Meplat bigger then .375 :flute:
 

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Meplat = slap factor
Meplat + velocity = SLAP factor

Simply listen next time your bullet hits a pig..
factory goes Pfffft....
Cast with big meplat goes WHACK!!

Cast bullets rule!
 

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Meplat + Bullet weight + Velocity. = WHOMPABILITY
 

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I will be the odd man out and say that ... A wide meplat (.325x 300 grains)compared to a smaller meplat (.25 x280 grains) shot within 100 fps of each other... definitely does not always kill game faster nor damage more . Where the game is hit also plays into the equation substantially.
 

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I will be the odd man out and say that ... A wide meplat (.325x 300 grains)compared to a smaller meplat (.25 x280 grains) shot within 100 fps of each other... definitely does not always kill game faster nor damage more . Where the game is hit also plays into the equation substantially.
I do know the larger Meplat normally cause more trauma, whether or not it kills faster is at the mercy of lots of variables.

This I know for sure, same bullet weight and Meplat size, same shot placement, one shot from a Marlin 44Mag one from a 444, 444 Deer DRT, 44Mag runs up to 80 or so yards.
 

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Whompability... I like that... somebody needs to enter that term into a Wikipedia reference:

Whompability: Adj; descriptive composite factor of measurement derived from a lead projectile's variable characteristics.
Simplified, Whompability (W) equals the TKOF multiplied by the meplat diameter,

Where W= (
) x dMeplat
  • is the bullet mass in grains (1 pound = 7000 grains)
  • is the bullet velocity in feet per second
  • is the bullet diameter in inches
  • dMeplat is the meplat diameter in inches
Amen.
 

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Whompability... I like that... somebody needs to enter that term into a Wikipedia reference:

Whompability: Adj; discriptive composite factor of measurement derived from a lead projectile's variable characteristics.
Simplified, Whompability (W) equals the TKOF multiplied by the meplat diameter,

Where W= (
) x dMeplat
  • is the bullet mass in grains (1 pound = 7000 grains)
  • is the bullet velocity in feet per second
  • is the bullet diameter in inches
  • dMeplat is the meplat diameter in inches
Amen.
i second it!!!
 

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If I ever get around to casting them....
I have a mold here that's a 'standard lube groove' copy of the RD-265, and one of the cavities is HP'd.

There's also that ridiculous mold for my secret squirrel project....
One end has a .380" meplat. The other end is .400".

You're welcome to some for testing, if you need/want any.
 

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Whompability... I like that... somebody needs to enter that term into a Wikipedia reference:

Whompability: Adj; discriptive composite factor of measurement derived from a lead projectile's variable characteristics.
Simplified, Whompability (W) equals the TKOF multiplied by the meplat diameter,

Where W= (
) x dMeplat
  • is the bullet mass in grains (1 pound = 7000 grains)
  • is the bullet velocity in feet per second
  • is the bullet diameter in inches
  • dMeplat is the meplat diameter in inches
Amen.
Believe it or not, I've got a formula very similar to that I've been using for years, whether or not it's got any merit is anyone's guess!
 

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This is from the Taylor KO Factor Wiki

TKOF = Taylor KO Factor

Taylor KO Factor
is a formulaic mathematical approach for evaluating the stopping power of hunting cartridges. The term "KO" is an acronym for "Knock Out." The Taylor KO Factor (TKOF) is a derived figure that allows hunters to compare bullets with respect to stopping power. The TKOF was developed by John "Pondoro" Taylor, a famous mid-20th century hunter and poacher of African big game.

There is more on the wiki page
 

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FYI The term "MEPLAT" is pronounced many different ways by people. I was told by people who speak French it is a French word and two of these French speaking people gave me two different way to pronounce it. I do not know which is correct. One way was MA(as in ma and pa) MA...PLAY. The other was MAY....PLAH. The term "OGIVE" was said to be pronounced OH...JIVE hope someone out there can give us the definitive answer on how these words are pronounced.
 

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I've always heard MEPLAT pronounced as spelt and I'm well acquainted with people in the industry.

Ogive is pronounced Oh Jive.

Jack
 

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FYI The term "MEPLAT" is pronounced many different ways by people. I was told by people who speak French it is a French word and two of these French speaking people gave me two different way to pronounce it. I do not know which is correct. One way was MA(as in ma and pa) MA...PLAY. The other was MAY....PLAH. The term "OGIVE" was said to be pronounced OH...JIVE hope someone out there can give us the definitive answer on how these words are pronounced.
méplat is a French word which I believe was first used to describe the ends of galvanized wire in the mid 1800s ... where two méplat ends of the wire had to be perfectly flat in order to be connected.

Based upon my limited knowledge of the French language after six years of French in high school and college, and a few months in Paris, I believe the correct pronunciation to be, "meh-PLAY."

Ogive is definitely ōˈjīv ... a pointed or Gothic arch.
 

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Whompability... I like that... somebody needs to enter that term into a Wikipedia reference:

Whompability: Adj; discriptive composite factor of measurement derived from a lead projectile's variable characteristics.
Simplified, Whompability (W) equals the TKOF multiplied by the meplat diameter,

Where W= (
) x dMeplat
  • is the bullet mass in grains (1 pound = 7000 grains)
  • is the bullet velocity in feet per second
  • is the bullet diameter in inches
  • dMeplat is the meplat diameter in inches
Amen.

May I offer a change for clarity? Capital D for Meplat...

Where W= (
) x DMeplat
  • is the bullet mass in grains (1 pound = 7000 grains)
  • is the bullet velocity in feet per second
  • is the bullet diameter in inches
  • DMeplat is the meplat diameter in inches


This way we do not have 2 small letter d's representing.
 
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