I would like clarification on this because I could only find one post that slightly touched on the issue on reddit, but didn't clarify completely.
Currently in my campaign, my archaeologist bard has made the transition from bow to Arc Rifle with a dip in technomancer. However there is some debate on how many attacks can be made with tech weapons.
The clarification for the related fire rates is as follows on the 'Technological Weapons' page:
"Semi-Automatic: A semi-automatic weapon normally fires one shot as an attack. However, the user can take a full-attack action to fire twice, as if using the Rapid Shot feat (including taking a -2 penalty on all attacks). If the wielder has the Rapid Shot feat, she can use the additional shot from that as well, but the penalty for all shots fired in that round increases to -6.
Slow-Firing: A slow-firing weapon requires a full-round action to use, and thus cannot be used to make iterative attacks."
The Arc rifle is a semi-auto weapon, so my assumption is that a semi-auto rifle can be used to attack as many times in a round as your bab allows + the additional shots allowed from rapid shot. Logically, it would make sense that you can make multiple shots as easily as you can with a bow, since a semi-auto rifle would only require that you keep pulling the trigger; making this even more obvious is that tech semi-auto weapons have rapid shot built in (this weapon is logically so easy for anyone with proper proficiency to use, that you can basically fire an extra shot for free).
To me this seems clear, especially since the 'modern weapons' page on d20pfsrd states:
"When making a full-attack action with a single-shot or semi-automatic firearm, you may fire a firearm as many times in a round as you have attacks, up to the number of cartridges in the weapon (or more, if you can reload the weapon as a swift or free action while making a full-attack action)."
However, my party members believe that how it is explained under technological weapons implies that you can only make 3 shots EVER (no matter your bab). This is because it says a semi-auto weapon makes a single shot as a attack or two, or three based off of rapid shot.
Long Story short: Is the Semi-auto description under the tech weapons page simply saying you get extra attacks as per rapid shot, or that you can only make up to 3 shots BECAUSE of rapid shot. Id assume this works like regular rapid shot and allows me to make a regular number of shots based on bab + rapid shot. Only that I basically get double rapid shot.