Re: Threading a Needle - chronographing at 500 yards
Sure, I have been testing commercial Bentonite. This is a commercially mined clay that is used for a wide range of purposes, including "driller's mud (oil industry), mud-jacking, animal feed filler, lining dug-outs, and lots of other uses. I can buy it in 55 pound bags, it has been dehydrated and powderized so that it is the consistency of flour. Bag costs about 8 bucks. We simply pour about fill a 5 gallon pail about 1/3-1/2 with water and slowly add the clay powder. My buddy has a big egg-beater like attachment for an electric drill that dry-wall installers use, and this does a great job of turning the mixture into a thick mud. You could do this by hand by kneeding water and powder together but it would be much slower. They told me to be sure that we did not pour water into the clay, will make big balls that would have to be broken down.
We shot all afternoon testing bullets. The clay will get as thick as plastercine, we make up 11"x11"x4" blocks in plastic bags and line them up in a wooden trough-like affair. The bullets are quite easy to recover, usually stuck against the plastic on the off side of one of the layers. Created some incredible channels today since we were shooting closer and also tested some match bullets.
I have now shot the Barnes XLC 168 grain bullets into the clay at 1, 2, 3, 4 and 500 yards and have impact velocities. Have created a very neat bullet collection.
Have also got a group of small plastic bags with Hornady, Speer, Sierra and Nosler J-4 fragments. The Sierra 168 and 175 performed the best of that bunch but they did fragment after about 8 inches of penetration in the clay. The others were like bombs.
My buddy fired a shot through the chronographs at 15 feet with the Barnes bullet, had clay flying about 30 feet in the air and onto trucks parked about 40 feet back. Recovered a perfect mushroom. It was a great way to end the day, except we had some cleaning to do...