Please define "roll trigger"

[GaryBF]

Until joining this forum, I have never encountered the term “roll trigger”. Reading the post below on the virtues of the LP10 vs. the LP50 it is used a lot. I have read about triggers that break like a glass rod, and I have read about “creepy” triggers. For my benefit (and many others I suspect), can someone please define what the term “roll trigger” means? What makes a trigger a roll trigger? Is it by design or just the way it is set up, e.g. sear engagement? Is “roll” a thousand dollar synonym for “creep”? Thanks.

[Nicole Hamilton]

I'm no gunsmith, so I can't tell you how it's made, but a roll trigger is one that gives just the tiniest bit of feedback (by continuing to move a little) as you increase pressure right up to the release. It should still be pretty darn crisp and very predictable. Don't even think a roll trigger should be squishy like the one in a Glock! Nor is it quite the same as creep; I think most people use that term to describe a trigger that moves (usually, a lot more) and isn't very predictable. The idea of a roll trigger is that that little tiny bit of movement will be just barely enough to let you know, very predictably, that you really are slowly increasing pressure on the trigger just the way you're supposed to.

What I like about a roll trigger is you still get a surprise release, but it's not like total surprise. But realistically, it's a matter of taste. Some people (like me!) love roll triggers, some hate them. Like a lot of things in life, you just have to make up your own mind what you like and learn to ignore the folks who insist you got it all wrong! :)

[Bill177]

That description sound like either government speak indicating nonunderstanding of the subject - but a desire to expound on same...... or, an advertisement explaining how you will enjoy the new perfect product, even though it isn't perfect, by giving it a spin (and the spin a name).

My take: If the trigger moves - it has creep. However, in all mechanical structures there must be a movement to start the desired reaction. How much movement and how much that movement is percieved by the user is the real issue of trigger creep. Only an electronic (not electrical) "contact" point has no movement, but remember, the switch to actuate that contact is mechanical and will also exhibit movement traits similar to a mechanical trigger. Movement perception by the user will depend upon the device's adjustments and the quality of the parts that must move against each other. This brings to mind the term "polishing."

I too, have probably fallen victim to using way to many words to describe a simple subject. Either you like a particular trigger or you don't.

[eskinner]

I have guns with both kinds (roll and non-roll) and each feel has its advantages. It truly is a matter of personal taste.
Mechanically speaking, a roll trigger has a "face" between the hammer and sear which must be slid across before the hammer is released. A non-roll trigger has almost no "face" and so when the trigger moves (the sear), the hammer is released immediately.
If the sear/hammer "face" is rough, if can feel gritty. Many call that "creep". The term "roll" implies it feels like you are rolling a cylinder under your trigger finger (and there is no "grit" -- the sear/hammer "face" is very smooth).
I have guns with both kinds because I haven't decided which I prefer.
--
Ed Skinner, ed@flat5.net, http://www.flat5.net/ (shooting notes)
and http://conventionalpistol.blogspot.com/ (shooting blog)

[Nicole Hamilton]

That description sound like either government speak indicating nonunderstanding of the subject - but a desire to expound on same......

And yours sounds like no explanation at all except a desire to criticize someone elses. At least I know there's a difference between creep and roll.

[Nicole Hamilton]

If the sear/hammer "face" is rough, if can feel gritty. Many call that "creep". The term "roll" implies it feels like you are rolling a cylinder under your trigger finger (and there is no "grit" -- the sear/hammer "face" is very smooth).

I like this. Grittiness is a pretty good way to describe the difference between creep and roll.

[James Hurr]

Perfect clean break:

As force is on the trigger is increased to the ignition point, zero trigger movement occurs.
At the point of break the trigger causes the gun to discharge, the trigger is then free to move back. Often it is stopped by a set screw.

At the point of break trigger force can either drop to zero, hence it feels like breaking glass, or remain constant, or anything in between.
With a perfect design change in force and trigger movement on ignition would be imperceptible, giving a surprise shot each time.

Perfect rollover:
As force on the trigger is increased to the ignition point, the trigger moves continuously backwards with no steps, bumps or grittiness.

At the point of break there should be no noticable change in force on the trigger and the trigger should continue moving backwards as the force on the trigger continues to be increased, again giving no force feedback to the trigger finger and a surprise break every time.

Most triggers on the market are compromised versions of the above.

[Lents]

Good explanation.
I was just going to ask this question ;)

Also
http://www.targettalk.org/viewtopic.php ... py+trigger

A "crisp" trigger normally refers to a trigger with no movement until the instant before the hammer fall. As the finger applies more pressure, there is no perception of physical movement until the actual break.

A "roll" trigger allows for the feeling of physical movement as the finger pressure increases. The first stage of two stage triggers often display this. For some shooters, the roll trigger allows them to be sure they are, in fact, increasing pressure instead of just thinking it's increasing.

[Lents]

For some shooters, the roll trigger allows them to be sure they are, in fact, increasing pressure instead of just thinking it's increasing.

What if indicate the current pressure somehow ?
E.g. to have blinking LED which gets slower as shooter goes closer to trigger release ?

[James Hurr]

Perception of movement is much better than perception of change in force, plus your muuscles tire.
Which is why as you hold a weight it seems to get heavier and heavier.
I find a clean break trigger hard to use for this reason.

On the other hand with a roll trigger there is always movement to control.

[David M]

The old FAS pistol had a true roll off trigger, a small amount of travel after the second stage weight point, but by design as the sears let off there was a small amount of roll off the sear.
ie. the sear was not a sharp angle corner but had a slight curve on it.
This gave a feel of a slight drop in trigger pressure as the hammer spring pressure then helped to push off the trigger sear, giving a soft feel trigger release.
Similar soft feel triggers can be felt on S&W model 52's and SIG P210/240's.
These pistols you can win bets on the triggers not feeling that they will lift the weight, but the do.

They are very different to a creepy trigger which is just a rough sear travel, either first or second stage.

[william]

Somebody, please, mess this guy up.