Besides what everyone else has said, can you scope the current on the rail?
Perhaps you need to add a bit more of idle load so that the choke current is continuous instead of dropping to zero on every other line cycle.
don't have a scope

I put a 100 ohm resistor in series and messured the current tho.
47mA at idle, 485V
150mA at full blast, 385V
I either need to somehow regulate the voltage, have a constant current load at idle. adjust for a LOT less output power, or find a new power transformer.
Although PSUD does not have sinusoidal load current, it does have load current steps to check for unwanted ringing in the filter, etc. Fast rectifiers are good. Note that the choke input filter reduces peak rectifier current. For snubbing, I refer the reader to the textbooks. Choke input was almost required with mercury vapor rectifiers, since they were very unhappy with excessive peak currents.
no? when I was messing around with diffrent choke values, and diffrent capacitor values sometimes I would get some major ringing when a load was applied.
also PSUD2 is really slow when I have really small or big values. like putting another choke with a 100nF capacitor in front, the simulation takes about 180 seconds. but 100nF isn't usually used in the power supply filtering so, I guess it isn't a problem.
Ta. Note that electrolytic ESR specs are a maximum spec value at 20C, and typically will be much lower in value - but no issue. Also the choke inductance will be different as it will have a different ACV and DC current than your test setup.
You measured the idle DC current through the choke by adding an extra 100R in series and that indicated 47mA and 150mA at 'full volume'. That aligns with a simpler PSUD2 sim where everything after C2 is replaced by either a 10k load for about 47mA output, or a 2.55k load with 150mA output.
Can you describe your intended application, as full volume for a hi-fi amp is the onset of sinewave clipping, whereas a guitarist pretty much wants a square wave output from a sinewave input.
Using PSUD2 with a stepped load current change shows no ringing for that setup (with 100R test resistor moved), just some under or over shoot. You should find similar operation when increasing filter caps as long as you don't do anything too drastic (ie. keep output capacitance sufficiently larger than input cap). That should get B+ sag down to circa 40V.
Whether you need to reduce sag any more perhaps again depends on your application. For example low distortion doesn't necessarily require zero sag - there are so many other issues that would dominate that aspect.
yes I actually calculated the resistor values at first when I didn't know that you can just change it to be a current load not a resistive load.
guitar amplifier, 40watts, high gain amp, but there's a design I'm trying to replicate, but change just a tiny bit so I can call it 'my own'

the amp I'm trying to replicate is the guitalogist gromms high gain amp conversion. I've drawn a schematic by what you can see in the video. the NFBL switch is a mystery, he claims that it switches between 2 different resistor values.
Here's the shematic:
https://easyeda.com/evalc2636/guitalogist-high-gain-gromms-amp-conversionthe amp he's fixing I'm pretty sure is a Grommes 50PG2, in the video he claims it to be a Grommes 55PG, but the output transformer on it is in a diffrent place.
the grid stopper on the first stage seems quite high but in the last shot of the inside of the amplifier, the resistor is still the same 100k.
I'm having a hard time deciding how I can get as close to that sound as I can with fixed biased 6P3S's, since I need another 2 coupling capacitors to filter the DC bias voltage.
but the big problem is the sag, I guess I could fix that by cathode biasing the output but I like the ease of use with fixed bias and want more power

but I guess if my transformer can't keep up, than I have no choice.
I have seem to have lost the shematic for my amp, it's pretty much the same, except I've got a 10k resistor with a 470pF capacitor on the 1st stage. an AC cathode follower with a 430ohm biasing resistor.
and I have the fixed biased output. I've changed the resistor values on the PI to the same ones as they are in the Grommes amplifier and I still have that massive sag.
I'll draw a shematic of the amp and put it in this post.
it's not low distortion, it's just that it quickly drops in volume a LOT, and then goes back in about 1.5 seconds. which doesn't sound good, at least for me. and PSUD2 shows this very clearly.
here's the shematic of my amp
https://easyeda.com/EdLS/ranom