As I teased earlier, I had the opportunity to test my rig in Gene Beggs' 100y tunnel located in Odessa, TX. We shot some groups Thursday afternoon and then followed up with some additional testing Friday morning. Targets below. In summary, the tuner isn't magically going to turn Elmer Fudd into Tony Boyer. But it can be a useful tool that I will continue to explore.
Here is Thursday's target.
Shot 3 foulers (not shown) and then shot the 5 3-shot groups at 5 different tuner settings. This is the exact load, seating depth, and sequence I shot for the March 11 testing I published earlier in this thread. Both Gene and I were surprised how well the groups formed regardless of the tuner setting. FWIW, Gene measured the Setting 3 group at 0.096". At this point I'm thinking maybe this tuner thing WILL turn me into Tony Boyer.
Studying the target later that evening in the hotel, I noticed how similar the March 21 target is to the March 11 target. The March 11 target has horizontal stringing that I know is due to my errors in accounting for the wind that day. Evaluated on the basis of vertical only, the March 11 target pretty much mirrors the March 21 target.
Friday morning, I wanted to see if I could repeat the groups we saw Thursday at settings 3 and 4 and to see what happened if I turned the tuner past 4; ie to marks 5 and 6. I wanted to see the gun go out of tune so I might pick up on any patterns it might exhibit. Prior to shooting the target I adjusted the windage to center the group up and made a 1/8-MOA adjustment down on the elevation to get the groups to print below my 12 o'clock on the moth ball POA. Shot 2 foulers and then shot the record groups starting at tuner setting 3. (Foulers not shown. Gun was not cleaned after Thursday testing.) Here's that target.
Well, I got to see the gun out of tune except it was at the setting I thought was going to be in tune. I do remember the sequence of shots. High, middle, and low. I also had obviously over-adjusted the windage. Nevertheless, I shot settings 4, 5, and 6. 4 was fantastic, 5 had some horizontal, and 6 blew up.
Undeterred, I next shot 3 5-shot groups at 3, 4, and 5. #3 was okay but 4 and 5 were not good. My ES, which had been running in the low 20s, blew out to 49 fps and that may be contributing to the poor groups.
Next we thought perhaps we needed to make smaller adjustments, ie 1/2-mark rather than full-mark turns. So I loaded up 15 rounds with the plan to shot settings 3, 3-1/2, 4, 4-1/2, and 5. I also dialed the elevation down another 1/8-MOA. After the 4-1/2 group, I conceded the gun was not cooperating and so with the 3 rounds remaining, I shot the final group at a setting of 2-1/2. Wow! 2-1/2 is sweet. My ES was 25 for this group. And with this, we stopped.
So what did I learn? If I can find and maintain the tune, the gun will shoot very small. In my case, I believe "in tune" is anywhere from tuner setting 1 to 4. It's not going to be possible to consult an atmospheric chart for a tuner setting, reset the tuner, and have it shoot a 0.010" group right after the RO gives the command to commence fire. As tuner guys like Mike Ezell have advised, if the gun isn't shooting the way it should, make a small adjustment. If that doesn't help, try going the other way. Maybe with time I'll get better at predicting ahead of time where the sweet spot is hiding. But for now, I'm thinking I'll have to hunt and peck a little with the foulers prior to jumping up to the record target.
In closing I want to repeat that my primary objective in installing the tuner was to be enable me to precisely pre-weigh powder charges and then use the tuner to adjust the tune as conditions warrant. I believe with more practice and match experience, I will achieve that objective.
My thanks again to Gene Beggs for his sage advice and for the use of his wonderful facility.
