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Lloyd Smale
10-23-2006, 08:28 PM
Buddy AL anderson did this after dustin killed the bear with his .475 at 176 yards just to see what kind of velocitys he had at impact. Al is one of the few that could pull off chronoing a handgun at that range.

1. With the .475 even though Dustin and I have the same guns built at the same time 10 years ago mine runs the load he used on the bear almost 100 FPS faster, but my bullets were cast with harder alloy (probably by Lloyd) so they were 5 grains lighter. At any rate with 24 grains H 110 and a 420 LFNGC they started out at 1223 and at 176 yards they were going 1008 for a difference of 215. So at Dustins velocity they would have been going 925 when they hit the bear. When I started out the same bullet over 20 H 110 from a .480 Ruger at 1190 they were going 973 at 176 yards for a difference of 217 FPS.

3. .475 and 400 RCBS Keith Style bullet started out at 1136 and at 176 yards were going 956 so they lost 180 fps.

4. With my 4" .500 Linebaugh built by Dustin and a 440 Keith of MT Baldy design over 28 grains of H 4227 they started out at 1083 and at 176 yards were going 908 for a difference of 175, this gun and bullet were used on a black bear and I will have a short story on Dustins web site about it.

5. Last .500 Linebaugh I checked yesterday was a 480 grain LFNGC over 16 grains of HS6 and started out at 984 and at 176 yards were going 847 for a difference of only 137 so these big bullets may start out slow but don't slow down much.

And velocities can vary greatly from gun to gun as I was shooting 5 different .500 linebaughs recently and one would be around 60 fps slower than two others with the same barrel length.

Well thats it for now have to get outside and shoot between the heavy snow coming down.

Take Care,

Al

LAH
10-23-2006, 09:17 PM
Yes Lloyd, very interesting. One never knows till you put'em over the screens.

Creeker

Bass Ackward
10-23-2006, 10:36 PM
Buddy AL anderson did this after dustin killed the bear with his .475 at 176 yards just to see what kind of velocitys he had at impact. Al is one of the few that could pull off chronoing a handgun at that range.
Al


Lloyd,

I have played around some, but I made the process more efficient. I was more interested in velocity "after" penetration experiments and I needed a higher percentage of rounds to produce.

So I measured velocities at various distances, then I adjusted loads to produce those velocities at 25 yards. Much more efficient. Then I was able to measure velocity after going through various objects and mediums. It was helpful in understanding bullet hardness and meplat effects and how they establish range limitations. It changed my whole ideas about meplat sizing.

Dew
10-23-2006, 10:57 PM
Lloyd,

I have played around some, but I made the process more efficient. I was more interested in velocity "after" penetration experiments and I needed a higher percentage of rounds to produce.

So I measured velocities at various distances, then I adjusted loads to produce those velocities at 25 yards. Much more efficient. Then I was able to measure velocity after going through various objects and mediums. It was helpful in understanding bullet hardness and meplat effects and how they establish range limitations. It changed my whole ideas about meplat sizing.

In what way did it change your ideas about meplat size?
Very good info you gave I appreciate it.

Dew

TCLouis
10-23-2006, 11:30 PM
I think Keith said something like, 'Big hole in, big hole out, lets air in and blood out."

Big heavy boolit provides momentum . . . and momentum is where it is at as shown by the chrono data!

Lloyd Smale
10-24-2006, 03:55 AM
Our testing is going a simular route. Now that we know what the velocity was of dustin bear load were going to back these loads off to that velocity at 25 yards and penetration test them. A good amount of it has allready been covered during other penetration tests weve done but I guess were most interested in Dustins load. Im preaching to the choir here but these test sure to reinforce my preaching on big well designed cast bullets effectivness in the hunting field. This mostly started to show the people that were doubters of Dustins shot at the grizzly but its been a lesson for me too. I would have guessed those bullets would have loss twice the velocity they did.
Lloyd,

I have played around some, but I made the process more efficient. I was more interested in velocity "after" penetration experiments and I needed a higher percentage of rounds to produce.

So I measured velocities at various distances, then I adjusted loads to produce those velocities at 25 yards. Much more efficient. Then I was able to measure velocity after going through various objects and mediums. It was helpful in understanding bullet hardness and meplat effects and how they establish range limitations. It changed my whole ideas about meplat sizing.

Bass Ackward
10-24-2006, 08:18 AM
In what way did it change your ideas about meplat size?
Very good info you gave I appreciate it.

Dew


Dew,

You like putting me on the spot huh?

From my testing, hole size above 1" is almost entirely a function of velocity. Not bullet diameter or meplat size. Think about that for a minute.

In a simplification, if you are going to drive a cast bullet at cast bullet velocities that the size of the hole cut is a function of a measurement of a meplat than an actual bullet percentage. Like if you need .250 for a meplat (60% of 44 cal) to cut a 1" hole at a certain velocity, then .350 (@80% 0f 44cal) doesn't get you that much more. Maybe 1/4". You need more velocity to make a bigger hole. So all I need is a 60% meplat on a 44 caliber, 55% on a 45, etc.

Basically .... meplat size is WAY over rated. And it actually can be a detriment to you in cases. Like minimum and maximum effective ranges. Especially if you don't shoot rock hard bullets to hold the nose shape intact which has disadvantages too as you will see later. A 60% meplat is much stronger than an 80%er. Once you digest that, the hardness data makes more sence.

The eye opener for me was about hardness. Hardness is way over rated. Lead is weak no matter how hard it is. Any hardness and mix can and will break up if the right bone shape .... not structure is hit "at the right angle". If big bone isn't an issue like on a broad side shot, then you can use what you want as long as you know your minimum range for break up if it applies. With lead as a constant strength, the wider the nose, the greater the shear force at impact.

With a hard mix, once the nose breaks, you are stuck with what ever shape it broke into. Frosty bullets have surface cracks that can actually foster this. If that happens upon entrance, (the game is quartering toward you) you are in trouble. If it broke into a wedge, you lose your entire meplat effect never to get it back because you don't have enough velocity to correct it. With a softer mix, not only is the bullet more pliable to impact and likely to increase meplat size, if impact wears it down, it can repair itself to form some effective meplat.

Don't misunderstand what I am saying. Hard and wide is very effective as long as the bullet hangs together. Or as long as it has enough velocity to do the work for you. But break it up and results will be unpredictable. If I used hard and wide, my shots would be limited to broad side or running away shots. And if I need more meplat than 60% of bullet diameter will provide, I either increase the velocity which has limits with lead or I reach for a bigger gun.

Here is the key. Bigger .... bullet .... diameter .... lead is stronger." Bullet mass is paramount. In essence, the larger the bullet diameter, the less you need to worry about this stuff as you have a wider margin for error.

One more thing to consider is bullet stability. Stability in flight is the same as stability in flesh. If a bullet reaches a low enough velocity that it becomes wildly inaccurate, (like a wadcutter at 100 yds) then it will lose stability in penetration at that same velocity. Think about that for a minute. That's why some calibers over stabilize their bullets, like 30 and 338 where penetration is wanted. So, too wide of a meplat can actually turn inside flesh and then you lose that meplat effect altogether.