potential crits and confirmation, i forgot how they work.

[Mako Senako]

when a roll a 19 on a 19-20 crit weapon, am i supposed to tally up the hit then if that is high enough to hit an opponent's AC then roll a crit confirmation? The way my groups been playing it, if you roll a threat you roll again and whatever comes up on the 2nd hit you then tally up and determine if it hits the opponents AC and if it does you crit.

[The Archive]

Only 20s ever automatically hit. You do have to check if the 19 hits AC. If it does, then you can attempt to confirm the critical.

PRD - Combat wrote:

Increased Threat Range: Sometimes your threat range is greater than 20. That is, you can score a threat on a lower number. In such cases, a roll of lower than 20 is not an automatic hit. Any attack roll that doesn't result in a hit is not a threat.

[Backpack]

its that way to prevent 15-20 crit weapons from being uber OP.

[Gauss]

Step 1: Roll to hit. If you hit AND the roll was a critical thread roll the confirmation roll.

Example 1: I am using a 19-20/x2 weapon.
I roll a 19 with +10 in attack bonuses and I get a total of 29.
The Armor Class is 25 so I hit, and it is a threat.
I roll to confirm the threat and roll a 15+10 = 25, which against an AC of 25 is a confirmation.
I roll double damage.

Example 2: I am using a 19-20/x2 weapon.
I roll a 19 with +10 in attack bonuses and I get a total of 29.
The Armor Class is 30, so I miss.
Nothing else happens, no critical confirmation, no damage, a shame I didn't roll a 20 (automatic hit).

[GeneticDrift]

It's unusual that a die roll of 15+ can miss. Maybe a late iterative attack if combat isn't your main role or a fight you were not meant to fight.