Weird Hot End Temp Readings

So ive noticed that my hotend didnt seem to be pushing out a nice flow of extruded filament. I figured it could be my temperatures were off. I did 3 or so pid autotunes @ 220deg
having gotten the best values ive inputted them etc.....

However ive noticed that after doing so printing didnt get any better!! so i have a IR temp gun and figured id check out the temperature that my 30watt cartridge was putting out into the heat block. it was sitting about 45degrees out!

so to print out 200 or so im having to set my gcode at 245?? would this indicate the need to replace the thermistor or is there something set wrong possibly in my marlin code?

If anyone has any suggestions that would be appreciated.

Cheers,
Brad

Is your thermistor defined correctly?
Does it sit close to the nozzle or close to the heater?
Do you realise that those IR guns are
a) dirt cheap
b) low quality
c) pretty unreliable on shiny metal surfaces?

Tired with three different models, all gave a different temp and all produced different temps depending on the angle of "attack" on the hotend.

the hotend is a E3D-v6
as far as the actual thermistor, think its just a generic 100k NTC

the IR Thermometer i have is quite accurate within 3 degC, and have tested it to make sure. They are only inaccurate and cheap if you buy a crap model,
if you spend some decent money they work well and never had any issues with any of the ones ive gotten.

ill have a look through my marlin conifg and double check if thats all good, then may swap out thermistor and see if that does anything to help.
from memory though in the settings, there were multiple thermal settings that were all 100k with 4.7k pullup would it make much difference as to which one is selected?

If you have no clue what thermistor you have then replace it with a known type and use the correct thermistor table in Marlin.
Not going to explain why this important, so please read it up.

all good thanks , i think my settings were initially correct which explained why everything was fine, but when i swapped to new hotend i installed a different thermistor without realizing, so will change thermal preferences to suite as i found the specs on thermistor also.