where does the QA trigger sit when it is ready to be pulled? is it as far forward as the double action mode on the AS trigger? or is it closer to the rear like the single action mode of the AS trigger? or somewhere in the middle?
The QA is also DAO, but with a lighter trigger pull. If I'm not mistaken the QA's striker is partially cocked (ala glock) before the trigger pull. This partially cocked striker doesn't have enough travel or strength to set off the primer, so the trigger cocks the striker the rest of the way.
DAO starts from full rest, the trigger completely cocks the striker and releases it.
I don't have a DAO or QA, but the QA's trigger is supposed to be slightly lighter than the DAO. Also, the QA has a shorter trigger travel than the DAO.
You are right about the marketing to an extent. Some LE agencies only allow DAO pistols as it seems they don't trust their own officers. Also, they don't necessarily like the glock style action. So I'd say DAO does exist because of marketing to specific LE agencies. They put DAO on the side of the slide and the pistol magically becomes safer. Who knows...
Although the QA trigger and the AS trigger in DA start from the same position, the QA trigger breaks sooner, about halfway between the bump in the trigger guard and the rear of the trigger guard. The AS trigger breaks closer to the rear of the trigger guard.
Thus, trigger travel for QA is about a half of the distance for DAO and DA part of the AntiStress. And it's even 2 mm less than for SA part of the AntiStress (although QA trigger is almost twice as heavy as for SA).
That's on paper. I personally have not had a chance to shoot QA - local range has DA/SA only. QA I think is a great option for shooting and defense situations if only its short, 7 mm of the trigger travel does not make it unsafe. My guess this could be compensated by keeping QA explicitly decocked after loading the chamber (for storage, carying, etc). Does this make sense?
Or maybe Walter engineers calculated that 3,800 g / 8.4 lbs of the QA's trigger weight is sufficiently heavy to prevent accidental firing. Why in this case they created DAO then? It's almost like QA and DAO are kind of contradict each other... Can somebody clarify?
The QA Walthers have a trigger with the same weight as a Glock with a "New York" trigger, and a medium length pull also similar to a Glock. It looks like the QA is aimed directly at Glock and it's LE following.
The DAO Walthers have a traditional long and heavy DA pull, which is inherently safer than the QA but probably too heavy for a lot of people, especially those who don't want to practice much.
The QA is a compromise between the safety benefits of DAO and the desire for a lighter trigger pull, as are ALL partially pre-cocked striker fired semi-autos.
Funny, but I don't remember hearing as many complaints about the length and weight of DA pulls on revolvers before the big LE switch to semi-autos. I may be wrong, but it seems that people accepted 12 pounds as standard on a DA revolver, and no one was asking for a 5.5 lb (Glock) or a 6.5 lb (Sig DAK) or an 8 lb (Walther QA) DA revolver.
Lefty Sig - I'm not sure about exact numbers for Glock's "New York" trigger, but standard Glock's trigger distanse is 12.5 mm. QA has just 7 mm, practically 2 times shorter then Glock. For the weight: Glock's trigget has 5.5 lbs, QA has 8.4 lbs. Is this all similar on practice?