This situation really depends on where this occurs. At a major match, the Range Master is going to be using tested calibration ammo. However, for most clubs in the country they do not have calibration ammo that meets the requirements. So, what happens at a local club match?
True calibration gun and ammo must be between 115-125 power factor (sub-minor) per Appendix C1 #2. This is verified by shooting it over the chronograph using the gun or guns to be used by the calibration officer. However, at most club level matches they do not run a chronograph and at Level II matches chronograph is only recommended, not required.
So what happens if you get a calibration challenge at your local match? First, you must verify the competitor actually hit the challenged popper. We can discuss in depth the issue of not painting metal poppers between shooters, but if you determine the request is valid, where do you go from there? At most clubs, the RM or CRO for the stage (but every match should have someone who is acting as the RM or calibration officer) asks if someone is shooting production. They either borrow the gun and a couple of rounds or have the production shooter shoot the popper as close to the position it was shot from. However, remember, the place you shoot from must have at least 50% of the calibration circle available for full size poppers and 100% of the circle for mini poppers. (See 4.3.1.5, #1) This may or may not be where the actual shot was fired from by the competitor. If the popper falls with a hit on the circle or below, it is scored as a miss. If it hits anywhere on the popper and does not fall it is a reshoot. If it hits above the circle whether it falls or not it is still a reshoot. See Appendix C1.
The problem with this is we have no idea what power factor the production shooter is using. For example, Winchester White Box 115-grain ball runs around 135 PF out of my normal calibration gun. You might have a production shooter who is shooting factory loads, some may be minor, some have been found to run sub-minor, but you really do not know. If they are running reloads of various types, you again are only guessing. Now if you have an experienced, higher-class production shooter, they most likely know what they are running and you try to get as close to 125 PF as possible. Hopefully, none of the shooters in the squad will admit they are running sub-minor, hmmm.
Now, I have an advantage as I carry a box of Nationals tested calibration ammo with me at all times. I know it will run between 116-121 depending on what gun I am running. I have also loaded calibration ammo for doing initial testing at matches, so I can save the good stuff for challenges. The following are a couple of ideas on the loads we have used in the past. Of course, take these loads with a grain of salt and make sure you test them through your firearms to make sure they will meet the requirements. Most calibration ammo is 9mm but while recommended, it is not absolutely required. The load we run at the Nationals is a 147-grain bullet, but again that is not required. Ball or Hollow-points both work fine. The loads I have used are mixed brass, and 9mm bullets.
| Bullet | Powder Type | Grains of Powder | OAL |
| 147 gr Montana Gold CMJ | Universal Clays | 3.0-3.1 | 1.100 |
| 124 gr Montana Gold JRN | VV320 | 3.8-3.9 | 1.100 |
| 115 gr Montana Gold JHP | VV320 | 3.8-3.9 | 1.150 |
| 147 gr RN | Accurate #2 | 3.2-3.4 | |
| 147 gr Precision Delta FMJ | Titegroup | 2.8 | 1.130 |
All of these loads will run around 118-122 PF depending on your gun, barrel length and type. I found they run a bit slower in my Glock 17/19 and bit faster in my 5” 1911 type guns. Again it is critical to test the loads and work up to the power factor you want. All these loads are nowhere near maximum, but always be careful when working up a load. I’m sure if you want to make up a load using the powders and bullets you have, there are recipes on the various loading websites.
The key is once you have developed a valid tested load make sure your club keeps some set aside for those calibration challenges. It is only fair that you follow the rules if at all possible. I would hate to hear a competitor felt he was treated unfairly because the only ammo someone had at the match was some 140 PF stuff the RM had rolling around in his bag.
Be safe and I will see you on the ranges.