Skeetlee
Here is some testing done by Jackie Schmidt using a Oehler 35 chronograph and Berger 105's
Jackie Schmidt Rail Gun Project
« Reply #5 on: 09:00 AM, 01/15/06 »Reply Quote 1/15/2006 Report:
Jackie just finished up at the range, concentrating mostly on the Berger 105 VLDs today.
With the throat on our barrel right now, the Berger 105 VLDs seemed to be in a good position in the neck. Jackie said five-shot 200-yard groups were in the mid to high threes,i.e .35"-.4" actual measurement). He ended up with a sequential 5-group, 25-shot agg of .195 MOA at 200 yards. The Bergers liked RL15 the best, with CCI BR4 primers, loaded about .012-.015" into the lands. Vel = 2990+ fps.
This is real-world range performance, with a bit of wind to mix things up.
We are probably going to extend the throat about .030" to see if we can improve performance with the 107 SMKs.
Some interesting points:
1. The Lapua 105s have a diameter .0005" smaller than the Bergers, and may require a barrel with a tighter bore diameter for optimal performance. Our barrel has .237 lands, but the groove diameter is right at .243. A .2425 might work better with the Lapuas.
2. The CCI BR4s and CCI 450,sm. rifle magnums) chron'ed the same with RL 15.
3. Jackie got his best accuracy with the 105 Berger VLDs at 2980+ fps. His cases are on 9-12 reloadings now and Jackie says the primer pockets are still tight.
4. With RL 15, ES was running 10-14 fps, with SD 3-5 fps,This is across multiple strings of 5 shots PLUS sighters--usually 7-9 shots total). This is with turned necks but NO work on primer pockets or flashholes.
Waterboy