As long as you are happy with accuracy then it's not a problem...You might see a problem when you go to a deer load (75-100grs) of powder..
That said, it ain't normal either...
Patches normally burn through where they contact the rifling when you have problems and there are several reasons for this...
What were you lubing them with??? A cheap lube that I used for 25 years or so is SnoSeal...If the hole bothers you, put some wasp nesting between the patch and powder as an insulater...
Also, pillow ticking the last few years, like everything else we are getting from China isn't as good as it use to be...Might try another source...