[James Gates]

For some time I have expressed that it appears that Permanant Wound Channel was based on Meplat and Velocity and Penetration was based on Weight and Velocity. The "weight" is incorrect! I should have said Sectional Denisty instead of weight. As you know Sectional Density is the ratio of weight to the area of the cross section of the bullet. Therefore a lesser caliber bullet with the same Sectional Density as a larger caliber bullet (and the same nose shape) will penetrate the same if the Velocity is the same. Sorry about that! Best Regards, James

 

[Southpaw]

Mr Gates that's a very interesting and, I think, useful relationship you describe.  At least on my part, it's a relationship I never was aware of.  With all due respect, though,SD is ratio of the cross section of the bullet (bullet diameter) to bullet weight squared:
  (BW/7000)/(BD*BD).

God bless,

 

[James Gates]

Southpaw...Go back and look at your formula again and you will notice that it is the bullet diameter, not the weight of the bullet in pounds, that is squared. The formula of Sectional Density (a bullet's weight in pounds, divided by the square of its diameter, in inches) has been used for years to compared the potential penetration of bullets. It works fairly well on bullets of near weights, however the more weight you add to the formula the further away one gets.The more advanced formula: Bullet Weight in pounds (w/7000) divided by the Area of cross section of the bullet (pi X Diameter of the bullet squared/4) gives a better factor for comparison of potential penetration. This works only if the Form of the nose is is same on both bullets and does give more consideration to the Mass of the bullet.In many of the published penetration numbers we see nowdays the nose form factors is grossly overlooked on bullets of the same Sectional Density. All these numbers are nice to play with on a rainy day and may give some insight in comparing one bullet's potential against another, however they have little to do with actual killing power. Physics says that a bumblebee's body weight compared to the area of its wings times the strokes per second....the bee can't fly! Think about that the next time you ponder the physics formula in ballistics! That is exactly way we run actual tests in the field on living tissue.
Best Regards as Always, James

(Edited by James Gates at 7:21 am on Aug. 14, 2001)

 

[Jack Monteith]

(Edited by Jack Monteith at 9:24 am on Aug. 14, 2001)

 

[Southpaw]

Jack, thanks.  The wording is wrong, but the formula is correct.  Also, I should hope that anyone using the results of any penetration, TKO, LI, etc. formula, would use them for comparative purposes only, not accepting such results as fact without some kind of validation through experiment.

God bless,

 

[arkypete]

Gentlemen
I wouldn't interrupt your learned discussion , for all the lead it would take to shut up a liberal.
But does this really matter if one follows the true and rightous path of 45 caliber?
A 45 caliber hole in most anything tends to make most discussions moot!
Jim

 

[Coldfingers]

Pete,

Spoken like a true southern genteelman who just did not have time to dink around makin little holes.

8*)

James,

It is sooo nice to see you posting again. Just got back from a miserable camping trip in the very soggy tundra. It rained EVERY day and the only critters we saw were floating by at a high rate of speed. Yuch! Hunting up there was at it's all time worst in all the years I have gone. The only holes we made were in the tent floors to let the water out!

Scotty

 

[Alan]

Scotty -

Add a little more rain and misery and you'd have been camping during western Oregon's late Blacktail season!  And gnomes...don't forget about them gnomes (he he he he)

James - looking forward to more updates.  I know you aren't having any fun having to go out into the field and all to gather this data but we the little people applaud you for your efforts  :biggrin:  (I wish I knew how to change the color of the smile to envy green!)

 

[James Gates]

Alan...I doing my share by putting ammo together. The shooters involved are not members of this, or any other Forum. I am trying everyway to keep theses tests as unbias as possible. These shooters a meat river/ranch shooters that live with a handgun on their hip (as I do)everyday! The care nothing about the finer art of ballistics! They look for results (read meat on the ground). To them, happiness is a large gut pile. Some paper shooters may not like this, but they sure as #### serve the purpose for us meat hunters.
Best Regards, James

 

[Alan]

"To them, happiness is a large gut pile. Some paper shooters may not like this, but they sure as #### serve the purpose for us meat hunters."

I've never cared for the flavor of grilled 8 1/2 X 11.  It's too dry and like Chinese food, leaves me hungry  :cheesy:

 

[James Gates]

Alan and All....For most of my handguning years, since 1956, I have been straddle the barb wire fence of handgunner's mindset. On one side has been the meat shooter that is more or less satisfied with what has proven effective ( slow to change). where on the otherside dwells the Avant Garde of the handgunner experimenter, who searches for the new and better (quick to change). Traveling my route can be rough! The hunter/shooter says I should be satisfied and am wasting my time chasing rainbows, where the other side is I'm too conserative (bigger is better). However,I can live with that. I think both side are equally important! It's like the old saying that goes somewhat like: "Don't be the first to lay the old aside or the last to pick up the new!"
The balance point of both sides is were realitic progress is made.
Best Regards, James