My son is still gathering data and the final results may take another two weeks to finish but I couldn't resist posting some of the results of the first round of testing. His teacher wanted him to only have one variable for the science fair so he picked 3 different size bullets as that variable. The bullets chosen were all 54 cal and included the .535 round ball, 310 grain Buffalo Ballet and home cast 410 Maxiball.
The test setup included a chroney for velocity of impact, each bullet weighed before and afterwith each shot into a container of damp clay. The depth of penetration and amount of expansion were measured todetermine the performance of each round. The retained weight was also a data point tracked.
What I wanted to do was to test at 3 different powder levels to similate different impact distances but we did not have time on the first session. It took much longer to dig the bullets out of the damp clay than we had anticipated. We had a total of 11 usable shots in 5 hours (a 12th shot was unusable due to a malfunction of the chronogragh). The fact that it was averaging right around freezing didn't help with the damp clay either. I nearly got frost bite digging in that cold clay.
We hope to do a little more testing next weekend if I can get back home, did I mention I'm having to travel alot these days? Any way, here is the data so far, I'm still waiting for my son to finish measuring the expansion.
410 Maxiball, 3 shot average
velocity = 925fps
pre weight = 26.6 grams (410.5 grains)
post weight = 26.43 grams (407.8 grains)
% retained = 99.6
penetration = 16.17 inches
The testing was done with 60 grains of Pyrodex RSat 5 yards so the velocities are basically impact velocities. We are hoping to finish the 4th and 5th shots for the Ballet and Maxi's next week if everything works out. I may even get to do a few shots at the other powder levels if we have time. You will notice the Ballet's were a bit slower than the Maxi's, I think that is due to the hollow base Ballet's may not have obturated enough to fully seal the bore with such a light powder load, they also had the largest spread in velocity, 200fps. Also at these impact velocities the Maxi's didn't really expand much if any but with 16+ inches of penetration who needs expansion. The Ballet's also had some that didn't expand much but I think that has to do with the impact velocity varying so much.
One other thing I did as a reference, but it may not be valid, was to shoot one shot into the clay with my 30-30. The 150 grain bullet only penetrated about 8 inches but the impact velocity was 2490fps so it was too high to similate a normal range shot. I may need to set the container out at 100 yards and try that again to see what kind of penetration it get at a lower velocity. I do have to say the 12" diameter crater it created was impressive, none of the ML loads came even close.
More to come as he gets the other things done. Maybe even some pictures when I get home and download them.
__________________
David
Only one man in a thousand is a leader of men -- the other 999 follow women.
Groucho Marx
Neat stuff murph. I'm very interested in what kind of crater the round ball produced, and how it compared to the Maxiball.
__________________
My wife says I'm totally nuts, but I think I'm Semisane.
Things I've Learned: (1) It's not possible to please everyone, but quite easy to piss everyone off. (2) If you love animals as I do, then you're not a vegetarian. (3) There's no need to act stupid, even if you're very good at it. (4) If you eat right and exercise, don't smoke or drink, you're going to die anyway.
My son is still gathering data and the final results may take another two weeks to finish but I couldn't resist posting some of the results of the first round of testing. His teacher wanted him to only have one variable for the science fair so he picked 3 different size bullets as that variable. The bullets chosen were all 54 cal and included the .535 round ball, 310 grain Buffalo Ballet and home cast 410 Maxiball.
The test setup included a chroney for velocity of impact, each bullet weighed before and afterwith each shot into a container of damp clay. The depth of penetration and amount of expansion were measured todetermine the performance of each round. The retained weight was also a data point tracked.
What I wanted to do was to test at 3 different powder levels to similate different impact distances but we did not have time on the first session. It took much longer to dig the bullets out of the damp clay than we had anticipated. We had a total of 11 usable shots in 5 hours (a 12th shot was unusable due to a malfunction of the chronogragh). The fact that it was averaging right around freezing didn't help with the damp clay either. I nearly got frost bite digging in that cold clay.
We hope to do a little more testing next weekend if I can get back home, did I mention I'm having to travel alot these days? Any way, here is the data so far, I'm still waiting for my son to finish measuring the expansion.
410 Maxiball, 3 shot average
velocity = 925fps
pre weight = 26.6 grams (410.5 grains)
post weight = 26.43 grams (407.8 grains)
% retained = 99.3
penetration = 16.17 inches
The testing was done with 60 grains of Pyrodex RSat 5 yards so the velocities are basically impact velocities. We are hoping to finish the 4th and 5th shots for the Ballet and Maxi's next week if everything works out. I may even get to do a few shots at the other powder levels if we have time. You will notice the Ballet's were a bit slower than the Maxi's, I think that is due to the hollow base Ballet's may not have obturated enough to fully seal the bore with such a light powder load, they also had the largest spread in velocity, 200fps. Also at these impact velocities the Maxi's didn't really expand much if any but with 16+ inches of penetration who needs expansion. The Ballet's also had some that didn't expand much but I think that has to do with the impact velocity varying so much.
One other thing I did as a reference, but it may not be valid, was to shoot one shot into the clay with my 30-30. The 150 grain bullet only penetrated about 8 inches but the impact velocity was 2490fps so it was too high to similate a normal range shot. I may need to set the container out at 100 yards and try that again to see what kind of penetration it get at a lower velocity. I do have to say the 12" diameter crater it created was impressive, none of the ML loads came even close.
More to come as he gets the other things done. Maybe even some pictures when I get home and download them.
Send me a PM of the individual values (11 values)of each shot and I will run a "One Way ANOVA" on the data to test the Hypothesis "No Statistically Significant Differences" between penetration or weight retention on each bullet. May do a Non-parametric 1 Way Anova, since sample sizes are small.
Chap
__________________
Chapman Gleason
Purcellville Va
http://www.the-gleasons.com
That's outstanding stuff!
Good reference material for any Ml shooter. Are you going to post all the results when it's completed?
I'd be very interested in the performance of that Maxi.
I need to post a correction, the % weight retained was wrong. They should be 99.4, 99.6 and 99.6 respectively. I'll edit it in at the top.
Semisane,
The round balls made about a 3 to 4 inch wide crater about 3 to 4 inches deep. After that it was about as wide as the ball had expanded to. The Maxi's didn't make awide crater, maybe 1.5 inches but they drove right down into the clay without expanding much if any at that speed. One interesting thing about the Maxi is that if you launch it at around 1400fps it drops to the impact speed of the test at somewhere around 225 yards.
Mcawful,
I may try to post it depending on how much there is, I may only post the averages since posting the full list may be too much to post. Will have to see when it's done.
__________________
David
Only one man in a thousand is a leader of men -- the other 999 follow women.
Groucho Marx
That is really interesting... especially the velocities with that powder charge...
__________________
"Life should NOT be a journey to the grave with the intention of arriving safely in an attractive and well preserved body, but rather to skid in sideways, a total wreck, screaming Yahoo, with a big smile on your face."
ORIGINAL: gleason.chapman
....I will run a "One Way ANOVA" on the data to test the Hypothesis "No Statistically Significant Differences" between penetration or weight retention on each bullet. May do a Non-parametric 1 Way Anova, since sample sizes are small.
Chap
Huh??
__________________
Hey Fred, you go up on that ridge, I'll go down in that swamp, we'll get that buck.
Don't let it bother you, Wonk. A One Way ANOVA is never going to work. I think they'll have to go with a Double Congested Hyperthalmus and back that up with a Reverse Whompersniclke.
__________________
My wife says I'm totally nuts, but I think I'm Semisane.
Things I've Learned: (1) It's not possible to please everyone, but quite easy to piss everyone off. (2) If you love animals as I do, then you're not a vegetarian. (3) There's no need to act stupid, even if you're very good at it. (4) If you eat right and exercise, don't smoke or drink, you're going to die anyway.
ORIGINAL: gleason.chapman
....I will run a "One Way ANOVA" on the data to test the Hypothesis "No Statistically Significant Differences" between penetration or weight retention on each bullet. May do a Non-parametric 1 Way Anova, since sample sizes are small.
Chap
Huh??
This is to help David's son to give a little scientific validity to his experiment. To just compare averages on penetration or weight retention does not answer the whole question. The steps in a scientific experiment are:
Observe something
formulate a hypothesis
collect the data
choose a rejection region (usually .05 or .01)
test the hypothesis
reach your conclusions
So for David's son's expeiment the above steps were:
We observe that different bullets perform differently
There is no difference in bullet performance
they have collected the data but are not done, with two measurements on each shot, penetration depth and weight retention
The null hypothesis is "there is no statistically significant differences between penetration for those three bullets"
I will do the statistical test, which is called a 1 way ANOVA
So that is the statistical part of the scientific experiment his son did.
Hope that helps. Chap Gleason
__________________
Chapman Gleason
Purcellville Va
http://www.the-gleasons.com
My son's science experiment
