Riley.....I found a pretty easy, effective, and inexpensive way to test using water. Find, or build, some kind of box approx. 2' in length with a large enough window in each end to shoot through without blowing out the far end. It needs to be pretty tough/well constructed or you will blow the sides out with the bullet energy created. Line the box with a 45 gal. construction clean up plastic bag. Back this up with your wet paper or similar to catch the bullets that don't come apart.
They will have expanded about as much as they are going to by passing thru the 2' of H20. You can easily find most of the bullet fragments/jackets in the bottom of the garbage liner. You can place a lid loosely over the box if you want to help contain things a little, but beware, I have launched lids 30' in the air
. Also, don't shoot from too close unless you want a fresh shower every shot!
If you place the liner starting out with the top of the bag as far into the box as possible, and then raising it each shot to get above the holes, you can usually get 2-3 shots/bag. If you want to add some bone, wood, or what ever for more effect, you can easily do that. Also beware that the unexpanded bullets will travel through a lot more material even after going thru the water so a good back up is necessary. With an expanding bullet, normally the lower the velocity, the farther it will penetrate........Rich