malobukov

Paracast covers many shooting-related things, not just focused on USPSA competition specifically. The show has a unique flavor and they offer multiple perspectives, which is a nice touch (other podcasts tend to be repetitive after a while). I also find their humor less cringeworthy than Steve Anderson's, but YMMV.

Well, they promise that their ammo makes minor power factor, and it does.

Yep, same results.

Called Federal and was told that they don't measure muzzle velocity, just pressure, confirming what rowdyb said. If there are no pressure signs, they see no problem, even if there is 100 fps difference in muzzle velocity and power factor is 150. There are no recalls and nobody else complained. If I want, I can send them a box so they test fire and measure pressure. Was also told that they can change propellant twice in one week, so the difference in powder weight might be because of that. Not all lots of AE9SJ2 use the same load data, they just manage pressure. No wonder there's such variance in muzzle velocity from lot to lot. I see no pressure signs. I planned to use this ammo for matches, but I guess I'll burn it in practice instead, and consider it investment in my education. Good thing there are other manufacturers.

Yes, as long as you follow gun safety rules and don't scare people around you at the range. In the class that I attended there were several students who looked about C class. I did not ask about their classification, just listened to the cadence and looked at the hits, so it's ballpark. Not complete beginners, but people who would be at about 50% at the club match. Elias adjusted his one-on-one instruction accordingly. They shot the same drills, only slower, so no big deal. I also think they improved the most (it's easier to make progress when you have low-hanging fruits to pick).

I had occasional failures to fire (one in several hundred rounds) until I switched to Winchester primers and started to look for the raised primers. Now I get maybe one per thousand. Still worse than factory, but not by much.

If your grip is neutral (symmetric left to right), then the muzzle would move only up and down during recoil. If your grip is weaker from one side, the muzzle will tend to also deflect towards the side where the grip is weaker. It's a bit more complex because the pressure is not applied exactly left to right or right to left, but the key is that lateral symmetry is no longer there. In the extreme case, consider shooting with right hand only and weak grip. During the recoil, your muzzle will lift up and towards the left, because you have four fingers on the right and only one thumb on the left. So every time you shoot the gun, its muzzle traces that slanted line. If you zeroed your gun with your grip for 124 bullets, a 115 grain bullet will leave the barrel sooner, and 150 grain bullet will leave the barrel later, so points of impact on the target will also be along that line. 150 grains will hit high left, and 115 will hit low right (the latter difference might be too small to be noticeable). In reality this is a crude simplification, and you might observe other effects, too.

I will venture a guess that 115 gr will be just like 124. Horizontal shift is more interesting. I would try switching hands to ensure this is not related to asymmetric grip pressure.

Is the shift vertical or horizontal? It is common for POI to be slightly higher with heavier bullets. Lower muzzle velocity means the bullet spends more time in the barrel, so muzzle can rise more.

I have no way to measure pressure, but suspect that the difference will be comparable (unless they changed propellant).

I don't mind anemic as long as it reliably makes minor power factor. But the difference between lots was surprising, I expected better consistency.

I recently bought another case of 9 mm Federal Syntech 124 grain TSJ (AE9SJ2) and noticed that it is surprisingly hot. The box says muzzle velocity 1,050 fps but it sounded supersonic. I ran it through the chrono and sure enough, 1,216 fps average over 10 shots. Previous lot shot from the same Stock II was 1,092 fps. I thought maybe they put 115 grain bullets, pulled several and weighted, no, they are indeed 124. But there is clearly more powder now, 5.2 grains compared to 4.6 in the old lot. This is approximate, as I might have spilled some powder when pulling the bullets, or got coating flakes mixed in, but is in line with what the chrono is saying. Isn't 150 power factor in +P territory? Federal tech support is closed until next year, I'll ask them when they reopen, but still curious if this is common.

The closest I have is median match percent in all 2017 area matches combined in Production by class. For GMs it's about 80%, way below 95% required to get GM card through match bump.

I think the main reason for the gap between classification percent and performance at major matches is that zeroing a classifier does not lower classification percent. I understand it was done this way to combat sandbagging, but I think there is a better way: Remove 5% below class threshold, but not lower classification when classification percent drops. Once you reach A class, you stay in A class (unless you get better and move up to M). Maybe add some exceptions, like personal request or no A class classifiers shot in last two years. This way there’s no incentive to hero or zero, and an occasional bad run is still not the end of the world since best 6 of last 8 are averaged.

Percentile system works with any distribution. More data points is better, but even with currently available data it's possible to set HHFs reasonably well by looking at, say, 50th and 90th observed percentiles and extrapolating from that to 99.5th percentile that roughly corresponds to HHF now. The right tail is not that different from normal.