I'm at level 43, hope to make it to 50 before the end of the day. Sometimes when I'm online, there are Lev 50's playing with me that can basically destroy anything in one shot. I can't tell, but many times they look like very very long shotguns and I usually hear them charging up.
Any idea what this is? What do most people consider to be their most powerful/best weapon?
The weapon you're describing is probably the Pale Rider. It's the most powerful magnum in the game, and when equipped with the Charge 4 part, you can do a lot of damage in one shot.
That being said, the Pale Rider+Charge 4 combo is pretty "entry-level" as far as high-tier setups are concerned. The gun can be occasionally found in the shop (though it won't be at some of the higher levels, like 49 or 50) and Charge 4 can be earned through (Illegal?) Custom Parts and Wanted mission rewards.
The absolute best weapon, I would say, is the PSG1 rifle at level 49 and with 5 slots. Level 50 weapons have a preset amount of custom part slots (the PSG1 only gets 3 in this case), while a level 49 PSG1 is only marginally weaker and can get up to 5. When equipped with Damage 6, Outrange 3, Autoloader, Gluttony, and Full Burst, you have an extremely effective and well-stocked weapon that is capable of dealing a ton of damage in a short amount of time. It makes nearly all enemies, even the tough ones like Scagdeads, Scarmigliones, and Norman extremely easy at any distance.
What makes it a better candidate than the more powerful Muramasa rifle is that it's semi-automatic to begin with and doesn't require cocking between shots or bursts. It's also much more steady, so a lot more of your bursted shots will actually hit.
A level 49 Drake with 5 slots and the Autoloader/Gluttony/Full Burst setup is almost as good, but it's not as effective at a distance even with Narrow 2 equipped. It's also worth noting that a level 50 Drake always gets 5 slots, so the difference between a max-slot 49 and a 50 isn't very severe.
Autoloader/Gluttony/Full Burst can only be obtained through (relatively) rare infection missions though. If you don't already know about these then do some searches on this board. I'm running out of steam with this probably overcooked explanation.
i dont know how much damage does a lv 50 drake inflict upon zombies but my windham lv50 has 3052 damage.. increased with a lv5 damage.. upgrade.. :D which makes it the strongest shotgun to me so far.. strongest Mgun high roller 3000 base at lv 50 but extremely slow.. i preffer mp5 with 2406 damage increased with 5damage upgrade obvioulsy muramasa mines at lv45 with 5damage increase total powa of 30460 and hand gun most powerfull that would be government lv50 with 5damage upgrade 6292 pale rider for the magnums.. got one lv 48 with 5damage increase powa 44428 with 3 slots.. this is my most powerfull weapon.. so far.. :D