10/22 ... aftermarket barrel ... whistlepig
"WhistlePig" gun barrel? I had to look that up and found it's a real brand of gun barrel company now called AccuLite Barrel -
https://www.acculite22.com/
I tell you, learn something new on THR ...
accuracy difference between a 10/22 ... with an aftermarket barrel... and a dedicated AR-22 upper
If you are talking about factory stock 10/22 with just the barrel swap, there are other factors to consider that can affect group size.
My 10/22 came with 7.5 lb factory trigger which will definitely add trigger input to move muzzle away from POA (Even though trigger pull reduced to 4.5 lbs after 4000 round break-in, I still saw trigger input induced push/pull away from POA). Factory bolt with non-captured firing pin will also add to increasing frequency of flyers. And if you are free-floating the barrel or using bull barrel without barrel band, you also need to factor receiver movement in stock to consider bedding the receiver to stock to eliminate movement when trigger is pulled.
For the "Real World Accurizing 22LR on the cheap" thread, consideration was made to test KSA bull barrel with 10/22 receiver but with factory stock parts, found heavy trigger and factory non-captured firing pin bolt would limit the bull barrel's potential -
https://www.thehighroad.org/index.php?threads/real-world-accurizing-22lr-on-the-cheap.898035/
So after Volquartsen 2.5 lb trigger kit (Now broken in down to 2.25 lb), CPC reworked bolt with captured firing pin, Tactical Solutions V-block to better secure the barrel to receiver, free-floating the barrel and securing the rear of receiver to full-size modular stock; even with factory taper barrel with 6500 round count, I am getting 1/2"-3/4" groups at 50 yards using CCI SV and 3/4"-1" groups with Aguila 40 gr LRN/CPRN consistently.
I read report of many dedicated 22LR AR uppers are capable of around/sub 3/4"-1" groups at 50 yards out of the box with CCI SV/Aguila 40 gr LRN/CPRN so if you are comparing factory stock 10/22 with just the barrel swap to AR22, group size could be comparable depending on the factory barrel you end up with.
Of course, sky is the limit to further accurizing 10/22 to produce smaller groups than dedicated AR22 upper out of the box like the
CMMG Resolute but not sure if there is a budgetary constraint. For me, I had considered swapping out the factory 10/22 barrel with an aftermarket bull barrel once rifling was worn enough to affect accuracy but 1/2"-3/4" 50 yard groups with CCI SV/Aguila 40 gr LRN/CPRN is plenty accurate for me. So the KSA bull barrel will stay on T/CR22 as I put the BCA dedicated 22LR upper through its paces.
And I want to point out the difference between "CMMG 22LR conversion bolt" compared to "dedicated 22LR AR upper". While they use the same magazine, operational accuracy is very different as dedicated 22LR uppers have typical 1:16 twist rate barrel with bore made for 22LR diameter bullet. But using conversion bolt in .223/5.56 AR barrels with 1:7/1:8/1:9 twist rate 16"/18"/20" barrels does not produce utmost accuracy and I use my CMMG conversion bolts for AR shooting drills at closer range.
I hope this helped.