In my mind the most informative data to develop is bullet differences, since that is what most people are interested in. Differences in powder, we know that one is more powerful than another by semisane shooting same volume of 777, goex, shockey gold, etc and gettting different velocities. Bullet design (round, hollow point,ballistic tip) is the experiment I would do and measuring penetration, expansion and weight retention %.

Different bullets at differnt velocities, all other variables are derived from these two, measure penetration, expansion and Wt retention. This is a "2 factor experimental design" with the randomization of bullets to the "treatments", this is all just fancy statistical lingo to say shoot the bullets in a way that biaes don't creep into your experiment. Lets say we have 10 round balls, 10 Horndary XTP and 10 TC SW, and lets say the weights are about the same 200g, since the Round ball is 190 or something like that. Lets say we have the following 3 levels of charge

50g
75g and
100g

use the exact same swabing method between shots, use the exact same primer, exact same powder. Now randomize the experiment by taking 3 pieces of paper the same size and writing 50, 75 and 100 on different pieces. Take 10 round balls, 10 Hornady XTP and 10 shockwave and put them in a hat mix them up.

Pull the first one out. reach into the 2nd hat and pick out a piece of paper, say it had 75 g on it, so bullet 1 is shot at 75 grains and then 3 measures are made: depth into sand
expansion diameter furthest point to furthest point
weight retention %
Label that bullet bullet 1 by placing in a plastic bag, with the measurements.

Pull 2nd bullet out at random, say it is XTPreplace the piece of paper from bullet 1 and mix it up have another person pull a piece of paper from the had, say that is 75g again.

do this for all 30 bullets

you will get a data matrix like this:

bulletshot at penetration expansion weight
RB 75g 4.3" .73 187g
XTP 75g11.7" .65 196g

etc

I will send you the formulas and your son can do the statistics for an "F-Test" to test the Hypothesis of no statistically significant difference between bullets for penetration, weight retention or expansion.

Chap

Sounds good, thanks.

Ok to weigh in here. I went to the end and just starting giving some info so you may have gotten some of this.

He is not really testing anything if he is not comparing anything. If he is just shooting at increasing distances, yes he has one varible, but all he has is the terminal ballistics of one thing, a PRB. What I would suggest (as someone who has a degree in biology and has judged science fair projects) is comparing 2 or 3 bullets with the same powder charge at given distances, maybe 25, 50, 75, 100, 125 yards. Create a hypothesis that he can test like PRB will have the best penetration, weight retention, and expansion of the 3 bullets tested. I like the idea of clay versus sand because I think you can get a more precise measure of depth. An idea is get an 8" by x" longpiece of PVC, split on bandsaw, fill with clay, hold together with string, shoot, split, measure depth, mix clay together, put back together shoot again. The more shots the better but a shoulder and the wallet can only take so much. Don't be bummed if you get a complete pass through the clay but try to make the clay long enough that most of the shots are stopped.

Feel free for more help. Reminds me of a science project that I did on penetration power of steel shot vs lead shot when we had to switch to steel in the early 90's.

Prepare to spend some range time putting 10 roundballs in that 8" tube at 150 yds!!

Might want to use a highway culvert instead!

It sounds like a cool project. I have suggestion for something to hold the medium in that could cost you nothing. I work at buffet, I was thinking of bring some of the empty fry oil contanier home and use to hold my targets when I shot other then at an range. maybe you could ask an eattery if you could have some. a good sharp razer blade can take the top off. I think the sides are to thick and can mess up your data. you could also ask if they have any old buckets (puddings, pickels and sometimes hard boided eggs come in them).

Thanks for the ideas. I have several 6 gallon buckets that I could use. Another idea I had was one of those 12" tubes from the lumber store that are used for concrete footing forms, they are about 3 to 4 feet long.

Dmurphy317

Check this out: http://www.modernmuzzleloader.com/phpBB/viewtopic.php?t=6450&start=0

Seems like the same stuff you want to buy from MidWay, but will take a lot of heating and cooling to shoot as many shots are you will need to shoot to do your penetraton experiment.
Chap

Thanks for the link. I'm not a full member at that forum so it will not let me see it. I have applied for membership so when it goes through I will check it out.

The thing I like about his ballistic gel, is you can see the bullets and then measure the penetration depth. With the green stuff you were going to buy at MidWay (he got his from Cabelas) I don't think you will see the bullets clearly. Chap

Here are my shots into a 5 gallon bucket back in 2004 with different bullets to measure penetration:

http://www.the-gleasons.com/bullets_penetration_tests_for_mu.htm

you will see that the side get blown out and the bottom gets blown out on the 5 gallon bucket, that is "wound channel". The 5 gallon buckets are not deep enough, maybe he 6 gallon are deep enough, should be at least 25 inches deep. As for 12" footer forms, I think they will be too narrow and will blow apart after a shot or two. When you hit packed top soil with a ML you really put a lot of power into a small area and it really blows it up. Chap