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Anchor Hardware Tested - Mussy Hook, Ram's Horn, Steel Carabiner, Lap links and chains

How worn down can mussy hooks be before they become dangerous? To find out we pulled tested 2 new Mussy hooks and three worn-down mussy's from 5 Gallon Buckets, an insanely popular climb at Smith Rock.

Before and After Pulling
Before and after pulling

Mussy hooks are a form of "Open System" meaning the rope can be clipped or threaded through the anchor without climbers untying the rope from their harness. Steel carabiners with captive eyes are another form of Open System anchor. Ram's horns, also called pig-tails, are the new kid on the block and are gaining popularity. We pull-tested all of them. They all broke super good enough. We did a bonus test with old lap links pulled off of an old route, chain links that are not welded closed. They broke at a lower force than the climbing ropes do.

Our Results

Our results show Mussy Hooks are ridiculously strong. The weakest well-worn mussy hook, which had probably been used by 5,000+ people to lower, broke at 46kn. That's over 10,000 pounds of force (lbf). Rams Horns began to bend at 4,300 lbf, roughly 10 times more force than climbers generate lowering, rappelling or top-roping. Steel carabiners break around 45kn. All of these anchors are insanely strong and way more than super good enough. Lap Links broke at 14kn which is slightly lower than dynamic ropes break at, but they are still super good enough.

*Breaking force is not the only part of an anchor. Rope grooves in fixed hardware can create sharp edges that can damage and even cut ropes. Inspect and evaluate any hardware you are going to trust your life to!

Route Cleaning

For single-pitch climbing Cleaning a pitch means getting yourself, your rope, and all of your gear off of the wall and safely back on the ground.

Rappelling, lowering off, and walking off are the most common ways to clean routes. There are advantages and disadvantages to all of them. Climbers will encounter routes that require each of these methods, so climbers should know how to do all three safely.

Open Systems vs Closed Systems

Closed Systems require climbers to untie their tie-in knot to connect the rope to the anchor to clean a route. This can be dangerous if a climber misses a step or gets confused. Speaking of steps, Closed systems require a lot of them. Cleaning a route with a Closed System anchor demand knowledge, focus, memory, and organization. Missing any step can be catastrophic. Closed systems make it impossible for the rope to come out of the anchor, this is their main benefit.

Open Systems require less knowledge and memory because they remove at least 8 steps when cleaning a route. We think that makes them safer. Open systems also ease traffic jams on popular routes because it is much faster to clean them. The disadvantage of open systems is that it's not impossible for the rope to come out, it's only extremely freakishly unlikely.

Take a look at how many steps are required for each system:

Lowering off of Open Systems requires only three steps, compared to 11 steps with a Closed System. Open Systems also make rappelling easier, removing 8 steps from the process required for Closed Systems.

Open Systems save a ton of time and we think they will also save lives.

Let us know which system you prefer in the video's comment section.

Lap links are unwelded chain links
They open under relatively low force

Accident Reports

There are so many steps involved with a closed system, human error risk increases. Here are just a few articles of fatal accidents where complexity was the culprit. And these were all experienced climbers.

What's Next

The worn-down mussy hook was super good enough, but this wasn't.


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