If you had a gun that would feed some, but not all factory ammo, what ammo are you finding works best?
I mean good defensive ammunition, if it doesn't expand well one might as well use ball ammo.

I know, get a better gun.  But I am still looking for the best ammunition for a problematic pistol.

Some of the 147 grain HPs are longer. Avoid those and focus on 110 & 124 grain loadings.

Try Hornady Critical Defense or something using their FTX bullet. In theory the plastic flex tip can help with feeding.

Any modern 9mm in good working order should feed JHPs. The Wonder Nine transition is what spurred the wide spread use of bonded JHP. If it is a new gun call the manufacturer. They have warranties for a reason.

Is the gun worn out? LEO trade ins are like high milage cars. They may run fine at the time, but expect parts to fail sooner than later. That's why they were traded in.  Little guns like the Sig 938 also have parts wear faster. For them it is an issue of mass.

If it's not feeding because of wear & tear, changing ammo will only kick the can down the road.

When was it made? Prior to the 1980s, most 9mm pistols were manufactured to use ball ammo. A thirty year old BHP could be new in the box and still choke on cup and core. Tuning service pistols to feed hollow points kept many gunsmiths employed well into the 2000s. Today's polymer pistol clones cost less than an old school smith.

The point is what you already know. Don't waist your money on premium ammo. Save your shekels up for a better gun. Don't get into a gun fight.

Hornady Critical Defense.

It's a first gen Springfield EMP. I have ordered new gen2 magazines, as these have been implicated in poor performance.

It's my daughter in law's gun. She would really like to get it running, I'm trying to help, but... You know.

Rem Golden Saber has a nice round fmj-like nose and pretty good performance… better than most but not quite at HST/GDHP levels. Rem GS even fed great in my M-11/9 machinegun and Kahrs. My MAC wouldn’t feed any other hollow points and my Kahr would have issues with HST/GDHP occasionally.

Hornady Critical Defense/Duty would feed in my tuned .40 limited gun … which are generally not known for their love of a wide range of bullet profiles.

There’s always that Corbon Powerball stuff, but that always seemed a bit gimmicky and on the lightweight & high energy side of the spectrum … not to mention $$$.

If I had to pick a JHP for “picky” guns, it’d probably be the Critical Defense or GS.  But in reality I would have the gun serviced to shoot proper HST/GDHP/RangerT/Sig/etc. or replace that gun.

Me too. I would rather have a reliable 380 than this gun as it's working now.

Yes I do. I wasn't to far off; micro nine in a century old platform for which it was not intended. Been there.

When I get a new auto loader I run a box or two of a number of makes to see what it likes and only carry those loads with that gun.

Current Inventory:
M&P 2.0 in 9mm does not care.  The only limit is the quality of the ammo, anything will feed consistently.  115gr, 124gr, 147gr, etc.
SIG P365XL is moderately picky.  I really does not like Speer Gold Dots, its pretty good with both Hornady loads but loves SIG V-Crown and Sierra hollow points which look exactly like V-crown to me.  It only likes 124gr though.
Beretta 92 FS - doesn't care.  Its just like the M&P   This is an old one too, from the early 80's
Kel-Tec PF9 - oddly it won't run on anything but hollow points.  Jambs up like crazy with round nose ammo.  Been to the factory twice now.  Its not a great gun, so I don't care all that much but the fact that it'll eat all the hollow points I feed it an not training ammo baffles me.

Federal 9BP

https://www.targetsportsusa.com/federal-classic-9mm-luger-ammo-115-grain-hi-shok-jacketed-hollow-point-9bp-p-2590.aspx

Have you tried G9 ammo? It may help the feeding issues.

I'd change out the recoil and hammer springs.

FMJ is probably too long.  Gun that small necessitates a fairly short stroke and ammo length ends up becoming more critical.

Firearms that are just for fun are allowed to be picky, firearms for serious social encounters must be perfect.

Get it fixed, or get a more reliable pistol is the correct answer.

You might find some nuggets here:

https://pistol-forum.com/showthread.php?46058-Springfield-Armory-EMP-reliable-9mm-sized-quot-1911-quot

Thanks! Good info.

Do you work for or have a financial interest in G9?

This.

Federal Hi Shok has a very nice profile close to a RN.
Standard Remington Hollow Points are very similar.
Even the standard Winchester HPs are good.

Agree with the advice earlier to avoid the 147gn bullets.

Dyslexia sucks.

Every time I see this thread, I see:  "Breast Feeding Defense 9mm"

Gold dot

It's rounded ogive closely matches ball

My experience pages 4-5

I think I was able to get it to run on 147g HST, which is my preferred load, but the whole experience (I think it was 3 times back to Springfield) made me not trust it.  It made my wife swear off semi-autos and I got her a .38 spcl revolver.

Great gun, fun, accurate but I won't trust mine.

I think the feed "ramp" is too steep.  It's really like a wall that the bullet nose slams into.  Rechamber a HP a few times and you'll see the nose gets crushes and the hollow point just closes up.

Springfiled customer service was fantastic.

If the pistol will feed 115-124gr FMJ/ball reliably then it will feed Federal 115gr JHP (9BP and 9BPLE).  
I have a 1970's Hi-Power and S&W model 39 pistol that had troubles with most JHP ammo but they would feed Federal 9BP reliably.

Dude, this was totally me.

Gold Dot 124, especially for PCCs.