Ian F.
12-29-2010, 09:55 AM
Took some of the questions from NitWits thread and brought them over here.....
I did a little math this morning...
The unit of measure of impact, and it's infered leathality is foot pounds of energy. That is what is transfered to the object hit by the projectile. The formula isn't too hard and I even found a website that does the calcs. Energy = Weight times Velocity Squared divided by 450395 (fixed constant) http://www.reloadammo.com/footpound2.htm
So with a little time on excel this morning I made the following table that covers most of the common velocities and weights in steel shells.
http://www.huntingbc.ca/photos/data/500/ftlbse-table.jpg
So what's this all mean?
There are some relationships, as follows
1. increases in velocity increases ft lbs of energy for a given weight of payload
2. increases in payload weight increases ft lbs of energy for a given velocity
Looking only at the ft lbs of energy numbers you can see a relationship where as you decrease velocity you can increase payload and maintain the same impact value. So a 1oz load going 1600fps (168ftlbs) is nearly the same as 1 1/2oz load going 1300fps.
So what's the big deal, why give a damn?
If you consider the actual projectiles and how many are going at the target then with the example above you have a 50% increase in potential killing pellets. The math....for #3's, that's 154 vs 231, which would you rather have on target?
Also, if you look at the numbers, and not the marketing you'll often find excellent shells that are not bank breakers! For instance my personal favourite duck load is a 2 3/4" 1 1/4oz going 1300ish fps by kent, $20 to $30 a case cheaper then the same thing in 3", wow that quarter inch of plastic can be pricey!
What's this really mean?
Use numbers to know where you are, and then your experience to know if you like that place or not.
There are many factors that come into play beyond this, which always makes for great discussion...choke? shooting distance? species? early season thin bird vs late season fat and fully feathered.
So at the end of the day, shoot as many pellets as you can, as fast as you can, providing you can hit the target, because the we can't forget about about Newtons second law..every action has an equal and opposite reaction....that's right recoil, and that is felt by each of us differently....
Some grissel to chew on....
Very best,
Ian
http://www.waterfowlzone.com/Hunting/shotgunpellets.htm
I did a little math this morning...
The unit of measure of impact, and it's infered leathality is foot pounds of energy. That is what is transfered to the object hit by the projectile. The formula isn't too hard and I even found a website that does the calcs. Energy = Weight times Velocity Squared divided by 450395 (fixed constant) http://www.reloadammo.com/footpound2.htm
So with a little time on excel this morning I made the following table that covers most of the common velocities and weights in steel shells.
http://www.huntingbc.ca/photos/data/500/ftlbse-table.jpg
So what's this all mean?
There are some relationships, as follows
1. increases in velocity increases ft lbs of energy for a given weight of payload
2. increases in payload weight increases ft lbs of energy for a given velocity
Looking only at the ft lbs of energy numbers you can see a relationship where as you decrease velocity you can increase payload and maintain the same impact value. So a 1oz load going 1600fps (168ftlbs) is nearly the same as 1 1/2oz load going 1300fps.
So what's the big deal, why give a damn?
If you consider the actual projectiles and how many are going at the target then with the example above you have a 50% increase in potential killing pellets. The math....for #3's, that's 154 vs 231, which would you rather have on target?
Also, if you look at the numbers, and not the marketing you'll often find excellent shells that are not bank breakers! For instance my personal favourite duck load is a 2 3/4" 1 1/4oz going 1300ish fps by kent, $20 to $30 a case cheaper then the same thing in 3", wow that quarter inch of plastic can be pricey!
What's this really mean?
Use numbers to know where you are, and then your experience to know if you like that place or not.
There are many factors that come into play beyond this, which always makes for great discussion...choke? shooting distance? species? early season thin bird vs late season fat and fully feathered.
So at the end of the day, shoot as many pellets as you can, as fast as you can, providing you can hit the target, because the we can't forget about about Newtons second law..every action has an equal and opposite reaction....that's right recoil, and that is felt by each of us differently....
Some grissel to chew on....
Very best,
Ian
http://www.waterfowlzone.com/Hunting/shotgunpellets.htm