I'm lugging more and more stuff to the shooting bench. The latest piece of equipment, thanks to the Yukon OK boys is an RSI pressure trace unit. Unfortunatly I had to provide my own lap top /ubbthreads/images/graemlins/crazy.gif After setting it up on the kitchen table, last night, and clicking the strain gage w/the button of a ball point pen and getting a trace for each click I figured I was in business. I then installed the strain gage on the barrel chamber according to instructions. I set up the data for the chamber and barrel as best I could with vernier caliper and a good guess at the chamber diameter at the proper location. Loaded up two stiff loads of 89gr IMR-7828 and 250gr SMKs. These are a full grain over the last ones I shot. Velocity was in the mid 28XX area. But wo is me, no pressure trace. A quick phone call to Burt @ RSI Manufacturing gave me enough confidence to mess with the trigger settings on the unit. As is normal for me, I adjusted for the maximum sensitivity. WaLaa- Pressure trace displayed. Wooo Hooo. Max pressure 58XXX, which seemed reasonable. No extraction or bolt opening negative symptoms whatever. The 250 SMK went across the chrony @ 2858 FPS. I did note a bit of a secondary pressure spike about 3/4 way down the trace. Interesting, says I? I don't like those things though I hear they are normal for the RUM cases but don't have valid data, yet. Second shot was again 89gr 7828 but w/Hor 225 SPs. Pressure went to 60XXX and a velocity of 2999. I figure that the increase in pressure with the lighter bullet is due to the Hornady being seating at least touching the rifling while the SMK is jumping just a little to reach them. I lost the first trace due to not being able to see the computer screen clear enough in the sun light to know what to do when. I have the second trace saved. Initial opinion: Its good. Discussion w/the manufacturer, a small shop, indicates they've done their home work. The more accurate the measurements entered during setup, the more accurate the pressure reading. The unit is simple and straight forward to use. And for us nerdy/geeky/anal/hungry for data types, I'd say its a must to have. More data will be forthcoming as I proceed with this flash tube idea.