Why is it that 115gr bullets aren’t used in matches?

[Harpo]

On 5/25/2019 at 6:13 AM, Localizer said:

My load is as follows:

 

115gr FMJ

6.6gr HS-6

various cases

CCI/Fed SPP

 

I bought HS-6 as it would work in all my pistol calibers...9mm, .40S&W & 5.7x28 and give great velocities without possibility of a double charge.

That's pretty much the load I started with.
And I think that HS-6 is a good powder to start with as a new pistol reloader because as you mentioned, it's hard to double charge, plus it's pretty forgiving if you're running on the top end(sounds like it's semi-common among 9 Major shooters) accidentally, and it gives pretty good accuracy.
It does get a little dirty on ~130pf 9mm loads, but it wipes right off.

Other powders to try later might be Titegroup(versatile, but has a low charge weight, which is fine if you have good quality control), Sport Pistol(sounds like it's similar to N320, but cheaper. Supposed to be cooler than Titegroup, plus a little "fluffier"), or W231/HP-38(classic powder for 9 and 45 ACP, and while a number of people run it with heavy bullets, Hodgdon doesn't recommend it for 147s, but it would be good for 115s or 124s)