gunarea
posted this
14 January 2011
Hey Fellas
After it warmed up a little this morning I broke out the chrono and fired enough round ball cartridges to fill up its little memory. Today the cartridges seemed to fit more tightly than I recall on past outings, maybe the cold.
The 134 gr projectile is loaded into a W-W super, 44 magnum case along with 4.6 grs of Alliant Promo and enough dryer lint to make sure the charge stays in position. Standard CCI large pistol primers are used and the cartridge is assembled through the use of a Dillon RL 300 press.
A Pact chronograph checked for velocity over a 24” trap. It was 51 degrees, relative humidity was at 35% and there was a light breeze. It was a beautiful clear blue sky on this cold ass morning. First shot fired was to make sure everything was performing as it should be, which it was, then another 21 shots followed.
Average velocity 926.9 fps, extreme spread 40.4 fps, standard deviation 20.2 fps
After reading Ranch Dogs projected values, I got out my micrometer, then began weighing over fifty of the as cast round balls. Diameter is .434 and weight averaged 134.7 gr on an Ohler digital electronic scale. Michael, the weight ran very consistant and my alloy is not pure lead. There is a small protrusive bump on the opposite side of the sprue and the sprue is much larger than what is present from any of my other moulds. These two protrusions along with my tendency to cast hot is what I suspect brings the weight up. A picture is in order but my digital camera does not have a macro and makes lousy close up pictures.
I was a bit surprised at the velocity deviation, the same powder charge under any of the four other 44 slugs I cast, run single digit values. Due to the large amount of empty space in the case, I use dryer lint as wadding and suspect this variable of composition and quantity may be the culprit. Another con to shooting these in a 44 mag case is that they don't produce enough pressure to properly expand the case enough to seal the chamber. All the spent cases are covered in smudge and it gets on your fingers, shirt, pants, chrono sheet, light baffle, face, camera, pencil, doorknob, soap, towel. Being a guy, I didn't notice until my wife pointed this out to me.
Thank you so much for promting me to do this research, it was both enlightening and fun. This was something I should have done many years ago. I am anxious to see your results of more playing with this fun bullet.
Roy
post script; Thanks Michael, for getting me past the fear of ruining my micro groove with the use of cast bullets. My old 336C has fired all seven of the different 38 cal bullets I cast and has done it extremely well. I see no need to ever again buy a bullet for my Marlin.