....interesting observation, thank you! My load for my 9c using the Hornady HAP 115grn @COAL 1.075" w/5.9grn of Power Pistol gives me avg 1134 FPS, the 125grn HAP @1.060" w/5.1grn of Power Pistol give avg 1002 FPS. Both cycle reliably and POA/POI is same from 7-20yds. My intent on these loads was to match as much as possible the Hornady Defense XTP load which I will be using as my EDC load. The HAP bullets are the same as the XTP bullet minus the expansion striations. My line of thought is I'll be able to get in more practice that will duplicate what the factory load will generate, but at a much lower cost. NOTE: This IS NOT the max load as indicated in Hornady's 9th.Third trip to the range with the FNS-9. Fired rounds 300 — 550. FNS-9 meeting or exceeding expectations.
Learned a couple of things, mostly about my reloaded 9mm ammo. With plated bullets @ 115 grains, using Tite Group powder, nothing less than 4.0 grains worked well. Erratic flyers and four or five failures to eject and two failures to hold the slide open at the end of the magazine when using lighter loads. Important to stress this is NOT the fault of the FNS-9; I am discovering the lower end of the power that it takes to operate it reliably.
I also learned that this gun gets hot. Tite Group is well known for being hot, that is, creating a lot of heat. And so it was with the FNS-9 after 100-150 rounds loaded with Tite Group. Is it possible the thinner barrel, the cold hammer forged steel barrel, does not dissipate heat as well as a less-expensive but thicker S&W M&P 9 barrel? Well, S&W has had their issues with the M&P 9 barrels particularly as it affects 115 grain bullets (changing the twist rate in 2012 or so).
I also noted some of my loads were not particularly accurate (I won’t name powders) while others, like 4.1 grains Tite Group with the Berry’s 115 grain HP round, were very accurate and functioned consistently. My conclusion, for Tite Group, go up into the 4.2 + range with 115 grain plated bullets. Next I will work up a bunch of 124 grain plated bullets to see if they, with a load more towards the middle-to-the-top of the recommended loads for Tite Group and HP-38, work more reliably in the FNS-9.
This pistol is turning out to be a lot of fun. My guesstimate is that it is made for +P “self defense” ammo and will function with it flawlessly. I have a box of +P+ LE ammo — will give that a try next time, too.
Until I can get more Power Pistol, I'll be switching over to TiteGroup and TrueBlue to see if same or similar results can be achieved.