Originally Posted by
klundin2000
Even though it was very hot, I had to get some rounds through my new Knight .45 Disc Extreme. After 3 sight in shots to get it on paper at 100 yards (with the lead bullets that come in the box), I settled into my very first 3-shot group.
I started with the Barnes 175 grain bullets. The first group measured 0.944" c-t-c with an average velocity of 2106 fps. This is with a weighed 89.1 grains of Triple 7 fffg powder using Winchester 209 primers.
When I tried the heavier 195 barnes and the 200 grain Shock Wave bullets, my groups opened up to about 2.5". Velocity with the same weighed charge averaged 2117 fps and 2156 fps respectively. I expected the heavier bullets to be slower but they weren't. Why???
One thing that bothered me, was the wild swing in velocity. For instance, one shot would be 2056 the next shot would read 2137 fps. I'm going to try Blackhorn power next to see if I can get those velocities to tighen up a bit. Maybe my goups will tighen also with the heavier bullets. I'm open for suggestions. kl
Rounding up the "Unusual Suspects" with T7 would be swabbing between shots-not to wet, and perhaps some extra breech plug grease contaminating the loads? And most prominent is barrel heating=sabot warping/melting.
Higher speeds for the later bullets could be a tighter fit=higher pressure, due to shooting on a fouled bore....???
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