Originally Posted by BH Hunter
MR: I wasn't questioning what you said just surprised by the performance. My Rum an off the shelf gun that I bedded and tuned the trigger on. The barrel is 26", I bought it the year they came out. I purchased a pro chrono just recently. I have it set up 15' from the barrel. I have very little experience w/ a chrono. I assume that when everyone says they are getting x fps out of their gun measured at the barrel it is actually 15 ft approx from the barrel?? Whatever the difference would be I assume it would be minimal. I did actually try Retumbo also and there wasn't much difference in velocity. I was also dissapointed by the velocity. 96 gr of H1000 was the most accurate load so that is what I settled on so far. I just loaded up the Bergers and out of the 5 loads I tested all but one were under 1".
BH, no worries, I didn't think you were questioning the data. I just posted that for informational background.
I corrected the velocities for the distance of 14' from my muzzle to the chrony. I used 8 fps and I determined that by running a BC calc for similar bullet BC and velocity and checking the differencr from muzzle to 100 yds (300') and mathematically worked out the loss in fps per foot and multiplied by 14.
You might try some heavier bullets to get more bang for the buck out of a powder like Retumbo. I would suggest 200 AB's and 210 Bergers. I'll be trying them as well out of my RUM with Retumbo and H1000. Also, if you get a 1" group @ 100 yds, you should check @ 200 and 300 yds. Your groups might still be 1" out there as it sometimes takes a couple of hundred yards for some bullets to "go to sleep".