DA/SA or LEM/DAO, which is better for preventing NDs?

[HammerStriker]

I know the best safety is the one between my ears, but we all make mistakes. Is a DA/SA less prone to NDs when holstering/unholstering, or is a DAO trigger like HK's LEM a safer? Why? Would appreciate everyone's feedback. Thank you!

[Sensei]

DA/SA will be marginally safer than the LEM. A 10lb DA trigger weight is significantly more difficult to pull than a 6lb LEM trigger if we are talking about objects entering the trigger guard during reholstering. The DA/SA has a more distinct hammer than the LEM if you are relying on hammer movement to let you know that something is amiss.

[beenalongtime]

Stupid question alert, but isn't the LEM also available on HK's striker guns? Are there any DA/SA guns with a concealed hammer that one couldn't put their thumb on?

[Sensei]

Stupid question alert, but isn't the LEM also available on HK's striker guns? Are there any DA/SA guns with a concealed hammer that one couldn't put their thumb on?

No, LEM is not available on the VP guns.

[beenalongtime]

No, LEM is not available on the VP guns.

Thank you (I think I was mixing up some models as some hammer appear bobbed by the photo's).

So either or even the C/D models of the Beretta's, shouldn't matter and just get into the thumb over the hammer habit.

[TheNewbie]

I know the best safety is the one between my ears, but we all make mistakes. Is a DA/SA less prone to NDs when holstering/unholstering, or is a DAO trigger like HK's LEM a safer? Why? Would appreciate everyone's feedback. Thank you!


I think they are close enough in first shot safety as not to matter. There are other items I would consider in regard to which is the overall best for safety and ability to shoot well.

Hopefully someone will link Dagga Boy's post about this.


I put a NY1 trigger in both my G17 and G26. It's not a DA press or an LEM, but it does add a little extra take up and makes the SCD even more positive in function. The reason I will not get a Gen 5 is I find the trigger a little too easy to manipulate and there is no NY1 option for the Gen 5.

[HopetonBrown]

DA/SA will be marginally safer than the LEM. A 10lb DA trigger weight is significantly more difficult to pull than a 6lb LEM trigger if we are talking about objects entering the trigger guard during reholstering. The DA/SA has a more distinct hammer than the LEM if you are relying on hammer movement to let you know that something is amiss.

I thought the FBI or sumbody did a study and determined that trigger travel, not trigger weight was more instrumental in reducing NDs, which is why LEM and DAK exist?

[TheNewbie]

I thought the FBI or sumbody did a study and determined that trigger travel, not trigger weight was more instrumental in reducing NDs, which is why LEM and DAK exist?

I've heard that too. I think the DAK is a great trigger that should have been improved a bit and put into a polymer platform.

[Bucky]

DA/SA requires more training, and commitment. With DA/SA, you have to remember to decock. Also, you need to prevent Hollywood wannabes from manually decocking their pistols, which has been cause for more than a few mishaps.

[HCountyGuy]

Any firearm with a longer trigger travel will help in reducing NDs. When it comes to holstering, a firearm with an exposed hammer can help make an ND almost impossible when the user rides the hammer with their thumb.

There’s a good argument that not needing to de-cock with a DAO/LEM provides less margin for error compared to TDA.

[BehindBlueI's]

Specifically in the context of holstering/unholstering, I doubt you'll see much (if any) difference. Unless you are holstering suuuuper gently enough to detect a snagged trigger, a 6lb s a 9 lb trigger isn't going to matter. No amount of travel is going to matter. Those are concerns for other scenarios, not necessarily holstering.

Something with a hammer/gadget is going to provide tactile feedback and the ability to stop the firing mechanism from moving before you complete the holstering...hopefully. A thumb safety (which I'm not a fan of) will allow for something to press the trigger without resulting in the gun firing as long as you remember to use it.

So, while I'm sure we could have a 38 page discussion on this particular angel dancing on this particular pinhead, the TDA/DAO/stiker/SAO seems like the wrong aspect to focus on in the narrow confines of the question. More broadly, there's a very lengthy thread on the differences in actual use, admin handling, etc already.

[Sensei]

I thought the FBI or sumbody did a study and determined that trigger travel, not trigger weight was more instrumental in reducing NDs, which is why LEM and DAK exist?

https://pistol-forum.com/showthread.php?21470-Info-on-FBI-study-regarding-trigger-weight-versus-length-of-pull/page5

[YVK]

There’s a good argument that not needing to de-cock with a DAO/LEM provides less margin for error compared to TDA.

I agree.


In addition, irrespective of LEM vs DA/SA, gun ergos make a difference. To me not all DA/SA are made equal. I distaste DA/SA guns with beavertails for carry because beavertails often prevent effective thumb trapping of hammer. So you don't get a feedback if the hammer has been lowered in the first place, and whether there is an obstruction during holstering.

[jlw]

DA/SA will be marginally safer than the LEM. A 10lb DA trigger weight is significantly more difficult to pull than a 6lb LEM trigger if we are talking about objects entering the trigger guard during reholstering. The DA/SA has a more distinct hammer than the LEM if you are relying on hammer movement to let you know that something is amiss.

This presumes that NDs will only happen on the DA trigger pull. I know of numerous NDs that took place on SA via either the shooter keeping their finger on the trigger after they had fired or due to forgetting to de-cock.

[JonInWA]

JLW above hit it on the head-in my opinion, DA/SA IF DECOCKED generally will require more poundage to pull the trigger, so presumptively it'll give you a bit more of a margin for safety, whereas LEM provides both a hammer and a longer triggerpull, but a significantly lighter triggerpull weight (usually similar to the pull weight of a single-action or a striker-fired action).

But the DA/SA margin significantly resides in that the gun is decocked and placed in the DA mode before re-holstering (or otherwise further manipulating when the need for the SA mode has gone and the prudent thing is to decock into the DA mode).

If you're placing a digit on the hammer to restrain movement when re-holstering, I'd say either action is then equally safe/rendered more discharge-proof.

Arguably the key thing is operator headspace and timing; if you're not prudent in all actions with a firearm, something will probably inevitably come back to bite you, irrespective of the gun's action per se.

Best, Jon

[GardoneVT]

I know the best safety is the one between my ears, but we all make mistakes. Is a DA/SA less prone to NDs when holstering/unholstering, or is a DAO trigger like HK's LEM a safer? Why? Would appreciate everyone's feedback. Thank you!

Wish there was a direct answer . Unfortunately the data available only reinforces the obvious; you cannot fix a software deficiency with a hardware solution, regardless of the hardware in question.

I’m thinking of a German government study on their national police and NDs which, broadly speaking, concluded some officers under stress instinctively trigger checked their weapons.

[David S.]

There are smarter thoughts and maybe even studies that can demonstrate one is better than the other.

I know we're all about picking nits around here, but I suspect both are within the margin of error for its ability to help you prevent ND's. I'd say, decide between the two systems based on other factors.

[That Guy]

Are there any DA/SA guns with a concealed hammer that one couldn't put their thumb on?

Walther P99 is a striker fired TDA pistol. So not exactly what you asked, but similar. (You can place your thumb on the cocking indicator hole, but the end of the striker pokes out of it only at the very end of travel. I find it isn't terribly useful from the preventing ND while reholstering perspective. You're more likely to feel resistance during reholstering, rather than feel the cocking indicator right before the gun discharges but not feel the resistance from something in the holster pushing on the trigger. I do of course still place my thumb on the back of the slide when holstering a P99, but mostly for other reasons (verify the gun is decocked, prevent slide from moving out of battery, commonality of technique).)

[M2CattleCo]

I say LEM because the trigger pull is always long.

I don't think DA/SA protects the user from himself at all. The opposite actually. It adds controls and manipulations and complicates procedures.

I don't think DA/SA is bad choice at all for dedicated users, but they are absolutely NOT something that will protect you from a bone-headed moment.

[farscott]

If I understood the studies properly, increasing trigger travel distance decreases ND occurrences. Part of this is that the reflexive closure from being startled is much stronger than even the worst DA trigger. Part of it is shooters sometimes expect the DA press only to find the hammer is cocked. Part of it is that increased trigger travel distance allows for time to recognize the trigger press needs to stop. As such, LEM is better than DA/SA for NDs as every trigger press is long. That does not mean that NDs with LEM are impossible. LEM provides more margin, not infinite margin.

There is, for me, an additional benefit to LEM. Because every trigger pull is the same, holstering does not require decocking the gun like a DA/SA gun does. One less control and one less thing to do. Proper training and practice can make running the decocker second nature, but LEM eliminates the step from needing to be learned and done. LEM, of course, demands more practice and attention to that long trigger press to shoot accurately and quickly. For me, the safety benefit of LEM outweighs the difficulty of shooting LEM well.

Really there is no right answer. As a regular person, in the event I am forced to fire a shot in self defense, I want that shot to be deliberate and not accidental. I also recognize that I will likely be a bit shook after such an event. After the one encounter where I thought I was going to have to shoot, the adrenaline dump gave me a really bad case of the shakes. I shook so bad I set the gun down and sat down next to it. Not needing to decock or safety the gun was a nice plus.

[Notorious E.O.C.]

Hopefully someone will link Dagga Boy's post about this.

BY YOUR COMMAND (https://pistol-forum.com/showthread.php?9457-Why-I-like-the-LEM-as-a-quot-street-trigger-quot).

[396]

Would there be a way of making a DA/SA pistol with a FCG that automatically decocked when just racking the slide, but left the hammer cocked when the slide cycled after a trigger pull?

ETA:Of course you'd still have to decock after shooting, dumb question, nvm.

[El Cid]

Startle response, sympathetic gripping, poor training, stupid people... I’m of the opinion all can and will overcome any trigger regardless of weight or travel. Drives me nuts when people want a hardware fix to a software problem. Just like the Army after Vietnam with the 3rd burst to stop full auto mag dumps. We have to treat the cause, not the outcome.

We need more/better training, which needs to include less pointing of firearms at people - not just inadvertently but when dealing with suspects. I can effectively cover a bad guy with my gun and not have it pointed at him.

[HammerStriker]

Startle response, sympathetic gripping, poor training, stupid people... I’m of the opinion all can and will overcome any trigger regardless of weight or travel. Drives me nuts when people want a hardware fix to a software problem. Just like the Army after Vietnam with the 3rd burst to stop full auto mag dumps. We have to treat the cause, not the outcome.

We need more/better training, which needs to include less pointing of firearms at people - not just inadvertently but when dealing with suspects. I can effectively cover a bad guy with my gun and not have it pointed at him.

In the day of 4-5.5lb. short travel striker-fired triggers, NDs are both a hardware and software problem. A piece of fabric from your clothing can pull a "modern" striker-fried trigger while re-holstering, it happens all the time. People are imperfect and make mistakes no matter how well trained they are. I do not buy for one second that all action/trigger types are equally forgiving/unforgiving. If humans could be perfect all the time, then yes, it is a software problem. I have yet to meet a perfect human, no matter how well trained. Heavier longer pull = harder to pull both intentionally and accidentally, it is just common sense. And before you site the research on on startle response, sympathetic gripping, there is no research that combines length of travel with trigger weight. A Hi-power with a 7-8 Lb trigger is super easy to pull, like a Glock. A DA trigger takes more effort to pull than a hi-power. A LEM trigger takes more effort to pull than a hi-power, even though it is lighter--this is due to the length of travel. I'm on the fence about which is a more difficult trigger to accidentally activate when comparing LEM and DA/SA. I'm leaning towards DA/SA being harder to accidentally actuate than a LEM trigger. It isn't only trigger pull weight that matters, but weight and travel combined. I don't understand how an objective individual could argue it is merely a software problem and that their stock Glock trigger is as forgiving as a DA/SA Beretta's.

[JohnK]

I don't believe I am immune from a ND with any gun if my internal safety isn't completely switched on all the time. I don't care if it is a gadget-equipped Glock, Lem, 1911 with grip and thumb safety, TDA Sig... what I do know is that if I follow the advice of a hard break from shooting before holstering, and knowing what the gun is supposed to feel like when holstering, and looking the gun into the holster, it works for me.

I have moved to an LEM P30 for, well, everything from now on because it works for me. When I was shooting my Sig 226, because of thumb placement on the hammer, I knew even before I holstered that something wasn't right (didn't decock automatically on two occasions) and it was the signal for me to do so. Never had an issue with a 1911 thumb safety for it to be on. So... I think it starts between the ears and goes from there.

[That Guy]

Would there be a way of making a DA/SA pistol with a FCG that automatically decocked when just racking the slide, but left the hammer cocked when the slide cycled after a trigger pull?

You're almost describing the Walther P99 anti-stress trigger. Although it does leave the striker cocked, only returning the trigger forward when the slide is racked.

[LSP552]

A lot of this is failure to understand how your gun works and failing to check and ensure empty before pulling the trigger. As a firearms instructor and Detective, I’ve investigated a number of NDs. The vast majority were deliberate trigger pulls on guns that were thought to be unloaded.

With semi-autos pistols and shotguns, it’s failing to understand how things works. If you rack the slide of a semi-auto pistol BEFORE you drop the mag, you will make the big noise every time! If you rack a round out of a chambered pump shotgun without unloading the mag tube, you are probably going to make the big noise.

People under stress often move too fast when the action is over. Adrenaline is a powerful drug. Combine this with not truly understanding how things work is a failure in he making.