Here's a link to my first video-test posting which shows tests of a screw lock, and one type of auto-locking biner:
Types of Biners you use.
However, based on the controversy Danny and I had, I decided to also test my biners which require an added extra action to unlock them. Here are the results:
(click picture to view video)
ANSI standard ANSI Z359.1 states:
"Snap hooks and carabiners shall be self-closing and self-locking and shall be capable of being opened only by at least two consecutive deliberate actions."
As well, Danny suggests the ANSI standard ANSI Z133.1-2006(8.1.11), which supposedly states "that it needs to have two consecutive, deliberate actions to
prepare the gate for opening".
The carabiner in this most recent video conformed to that different piece of the standard as well, and failed the test as well. All it took was a simple diagonal rubbing of the gate against a branch for it to pop right open....
an action I couldn't replicate with the screw-locking biner using horizontal or diagonal actions, even when doing so aggresively, untill after several minutes it finally unscrewed.
The action necessary to do so took a ridiculous amount of deliberate action, whereas unlocking the auto lockers took a simple single-stroke brush against it.
It is my personal opinion that screw-locks are inherently safer than auto-locking carabiners, and that many climbers are too lazy to use them properly. And that auto-locking biners can offer a false-sense of security and "fool-proof-ness".