Thread: What to do with .22 BRNO barrel?

I think with that length of bad bore your accuracy will definitely suffer.
Bulges are a bit different. One of the most accurate 22s I shot was a BSA with a bulge 1/2 way down the barrel. Bulges usually are less than a bullet length in length. I have a bulged Sako P54 which shoots extremely well. The bore either side of the bulge is very good.
As suggested you could try a good clean but include the throat as 22s are also subject to carbon rings. Autosol is very good just go easy using Autosol. You can clean forever with Autosol and continue to get black on the patch. This is parent metal.
Check the crown as suggested but also check for any flaring at the muzzle.