I caught a 4 1/4 pounder this year and thought it was a nice bass but didn't think it was worth taking a picture of. I thought it was a little under 4pounds before it was weighed. I have not caught 1000's of bass like some guys, but many of the bass I've caught are a decent size because I only target larger bass. I have caught a few bass 21-24" but never weighed them. A number of years back there was a bass in the Hammond for two springs that was an absolute monster. I was catching 2-4 pounders sight fishing and mistook this big bass for a boulder until it moved it's tail. I hooked it once on a 2weight fly rod...no chance in hell of course. The next year my wife hooked it after we spotted it and it snapped the line like it was nothing. It had roughed up the 8lb test with it's 40 grit sandpaper like lips until it broke. Never saw that bass again in the spawning areas and I bet it died of natural causes, unless it swallowed a worm baited hook too deep !
About 10 or so years ago there was a bass out in one of the channels of the Kennebecasis that was snapping our grubs off and it was a huge bass. We thought it was a big pickerel or small striper, but it followed to the boat a few times and just hovered there looking at the boat. It had to be at least 5-6 pounds. We had also caught a yellow perch that was 17" in that same spot that year... had to be something in the water! That was the biggest perch I have ever seen around here.
Last year during early July, I was fishing the Kennebecasis and hooked into a huge bass... it managed to unhook itself and I can't remember ever having a smallmouth pull that hard and it was not a striped bass or something else. I learned later from a couple different people who fished frequently a few hundred yards upstream that there was a 25-26" smallie near a bed there for much of the spring. One of the fellas had caught and released it while trout fishing.
I'm positive there are 6lb smallies in NB, but there are only a few bodies of water than can grow these larger fish. While striper or musky fishing I have caught some dandy smallies in the Saint John River. Some small lakes can grow monsters too. One lake in particular produced two bass one spring 10 years ago that were 23". I haven't fished it this year, but last year I hooked a hog beside the boat in less than 2 feet of water on a crankbait and thought it was a log until I looked down just as it spit it back at me. A month later I had a big bass snap off a senko in the same exact spot...probably the same fish. If you fish this lake in the middle of summer you would be lucky to catch a bass much over 2 pounds, but in the spring the big bass make themselves catchable.