Do you guys check for tight spots in your barrel

[Mark Palmer]

Thanks for that, what was your experience with the FPS consistency with the tight spots?

The fps variation was around 14fps over 120 shots both before and after polishing the barrel, I found that by pushing pellets in and back out of the barrel and examining them with a magnifying glass, I was getting uneven rifling marks,, I'm told this will cause poi shift /pellet sensitivity... it certainly did in my case. Now if a pellet is pushed into the barrel and back out of the breech from any where in the barrel, the rifling marks are even, like wise after pushed through the choke. An interesting exercise, im going to guess that the better guns/barrels out there get similar treatment? So called "match " barrels? PM me if you want to chat about it on the phone, it's too long winded to explain in text!

[Barryg]

Just an update and question, I have decided to refit my original .22 barrel as I have polished the tight breech end and the pellets now push through more even, the only thing is now the pellets fit in the breech without pushing them in like a chamber, I am using AA 16 grain 5.51 should I now change to 5.52 to get a bit of resistance or is a loose fit, OK?

Does a loose fit lose pressure Build-up?