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Visaman
September 1, 2010, 12:55 PM
1) for bullets with a weight between 138.9 grains and 154 grains the
minimum legal energy is 2700 joules ( 1991.4 foot pounds per feet) at
100 meters E100

2) with bullets weighting minimum 154 grains, the minimum legal energy
is 2200 joules ( 1622.6 foot pounds per feet) at 100 meters. E100


Is it possible to meet these energy demands with any of the cartridges listed, using REAL black-powder charges ?


The black powder cartridges:

.40-90
.40-100
.44-77 Sharps
.44-77 Remington
.44-90
.44-100
.44-105 Sharps (Necked)
.44-90 Remington
.45-70 government
.45-82
.45-90
.45-100
.45-110 .
.45-120
.50-100
.50-110
.50-140 Sharps
.450 Black Powder Express
.461 (.450) Gibbs
.500 BPE ( 440 grains bullet ,580 m/s)
.577 Express

Scorch
September 1, 2010, 01:43 PM
Visaman, you asked a similar question several weeks ago. The answer is that in order to meet the 1,662 ft-lbs energy requirements with a 154 gr projectile, you must propel it at approximately 2,200 fps. This is because kinetic energy is calculated

1/2 Mass X Velocity squared

1/2 Mass= 77 grains / 7000 grains/pound / 32 ft/sec/sec (acceleration of Gravity- required to convert weight units to Mass units)

You can see that with a 154 gr bullet, you must achieve approximately 2,200 fps velocity in order for the equation to be satisfied. This is easily achievable. A 7X57 can do it, easily. A 30-30 can do it, easily.

As far as black powder cartridges, they pretty much max out at 1,500 fps due to the limitiations of BP as a propellant. 1,300 fps is more common. In order for BP cartridges to achieve a target energy threshold, and being limited to lower velocities, they achieve the target energy by increasing bullet weight. Assuming 1,400 fps, bullet mass must be 380 gr in order to reach the 1,662 ft-lbs of energy required. If velocity drops, bullet weight must increase to make up the difference.

LaserSpot
September 1, 2010, 06:55 PM
The .500 BPE ( 440 grains bullet ,580 m/s) should have plenty of energy to make it to 100 meters. Several of the bigger cartridges you list could meet the requirement depending on how streamlined the bullets are.

Here's some load data. http://www.goexpowder.com/images/LoadCharts/Cartridge-Rifle.pdf

Visaman
September 1, 2010, 08:10 PM
The .500 BPE, barely makes it:

Ballistic Coefficient: 0.210 GL Caliber: 0.500 in
Bullet Weight: 405.0 gr
Muzzle Velocity: 512.0 m/sec Distance to Chronograph: 2.0 m

Range Energy
(m) (J)
0 3469.8
50 2804.9
100 2287.1
150 1880.0
200 1560.8

The charge is GOEX FFFg - 130grains

i am pretty sure it kicks a good deal.

LaserSpot
September 1, 2010, 09:43 PM
The ballistics are similar to a 3" 12 gauge sabot slug, but BP would make it a little worse; should be tolerable if the gun is heavy and you don't do too much shooting. This would be an impressive gun to shoot.

I guessed .25 for the BC, but I was just guessing.

sltm1
September 1, 2010, 11:24 PM
This is a very peculiar discussion. If you Google ballistic lethality, I believe it comes in at 250fps by any projectile, by government standards. At that speed, shot placement is the determining factor, not slug size or power, just accuracy.

RWBlue01
September 1, 2010, 11:32 PM
Legal energy demands?

Legal for what?

LaserSpot
September 2, 2010, 12:00 AM
Legal for what?I had to look it up. These are the requirements for big-game hunting in Norway.

Noz
September 2, 2010, 09:21 AM
I have a hard time believing that anyone would question the hunting effectiveness of a .577 Express.

Visaman
September 2, 2010, 10:32 AM
Well, regulations are regulations. even if i am pretty sure that a moose drops dead on a encounter with a .45-70-405 ( .45-70 Government, 405 grains solid round nose lead bullet) that crawls along at 1,394 ft/s.

But it does not have the minimum legal energy. :(

And if you are caught hunting big game with a cartridge that does not meet the minimum legal energy, well.. Goodbye Mr. Hunting license.

It is required that a cartridge/load does can be proved to meet the minimum energy levels.
A .54 Muzzle-loader can do that, and are legal in Norway
The problem is the reload time.

Jim Watson
September 2, 2010, 10:49 AM
A .45 - 2 7/8" (.45-110) should be able to drive a 520 gr bullet at 1350 fps for 2320 J at 100 yards. Assuming a ballistic coefficient of .36 which is conservative for those heavy Creedmoor bullets.

Mike Venturino's book 'Shooting the Buffalo Rifles' gives bullet weight and velocity for many BP calibres which can be entered into the program at:
http://www.jbmballistics.com/cgi-bin/jbmtraj-5.1.cgi
to estimate energy.

RWBlue01
September 2, 2010, 07:18 PM
Visaman, can you apply for an exemption?

Visaman
September 3, 2010, 02:00 AM
Getting a exemption is extremely unlikely.