This list will be covering the weapons that players can pick up around the map, or spawn with, for shop items please go here.
This page is a little bit of a misnomer being called 'guns' as the first thing we're about to cover is a Crowbar. Still, these are items you will spawn with each round, so they're guaranteed.
The great thing about TTT is that you can find a weapon you're comfortable using and feel some sense of reassurance during firefights.
These weapons will, generally, be available on servers that aren't modded beyond the basic TTT gamemode so they'll be more useful to learn on that basis.
Notably, the M16 is excluded from this list as it is disabled on the server; this is due to some issues with aiming-down-sights.
Of the available options, the most popular option is generally the Shotgun.
When you formulate a plan, you'll want a gun that can perform well in the condiitons you're intending to go through, the Shotgun covers a lot of these bases, especially on maps with tight corners, or that are smaller.
On an open level, or one with a lot of wide spaces outdoors, a Rifle can be a decent choice too. The MAC and HUGE are both difficult to use effectively, with the HUGE being a 'point at their feet and pray' option.
These guns, however, aren't guaranteed on every server but may be on a few.
I'll add the stats for the Overwatch guns as we play with them, as documentation is pretty poor.