DA Revolvers, Trigger Weight, and Safety Lever

[Lee Enfield]

Just curious about this... I understand that DA revolvers don't need a safety lever because of the heavier trigger pull that act as a "safety". It's also subjective depending on the individual's "feel" for the trigger weight, and the individual should have the greatest control over safety and the trigger. But, what if the trigger weight was reliably reduced... typically at what trigger weight threshold (range) would a safety lever be "necessary" (or, below what minimum trigger weight?)? Thanks in advance.

 

[testuser79]

It depends a lot on the source and when they're writing.

As you pointed out, to ensure proper ignition for most primers, I'd say 8 lbs is roughly the minimum, so you'll reach the limit of reliability before you reach a safety limit. I installed a competition spring once on a 686, and it seemed too light for general carry, especially in a coat pocket, etc.

Prior to the Glock, I think many would say 8 lbs or heavier with a long trigger pull. By the time you reached 5 lbs, you needed a safety, at least for 80 or so years. Many firearms writers in the 1980s were critical of the safe action back then due to safe concerns, over time that turned into, 5 lbs was OK with no safety and a hard sided holster. Some would morphed that argument into 5 lbs was and no safety and you should only carry a handgun in a hard sided holster.

Honestly, I don't like commenting on trigger pull threads. Usually you'll suggest a limit and several people will ring in and tell you how unsafe an owner you are because you're relying on any margin of mechanical safety.

For me, I'm comfortable 8 lbs with minimum with no safety, nearly all of my revolvers are setup that way 8-10 lbs. Then again, I have a NY trigger on the one Glock I have...seems about right to me.

 

[turkeestalker]

Lee this is just my opinion mind you, but I don't believe that a safety mechanism would ever be "necessary" on a modern DAO revolver any more than it would be on a modern SA revolver that uses a transfer bar safety system. The revolver is never cocked unless you put your finger on the trigger and pull, the same as a SA is never cocked until you pull the hammer back and manually cock it. Ultimately what it boils down to is keeping your finger off the trigger until you intend to pull it and fire. Without a finger on the trigger, it can not and will not fire by itself or accidentally without the trigger pulled fully rearward.

 

[Lee Enfield]

Let's say it's a 4.5 lb or less trigger weight on a DAO revolver that you have on hand. Say you're chasing feral hogs, or you're in the presence of a pack of wolves, or for self defense in a home invasion all within a 50 meter range (assuming no rifle or other firearm is handy), but you're concerned about accidentally discharging the revolver while running or when jostled in close quarters. Setting aside for a moment that it should rely upon the competence of the shooter to keep the finger off the trigger when not intending to fire... would a safety lever to keep a lighter/easier trigger pull in check makes sense here, or will the safety lever get in the way in the heat of the moment? I'm sure it depends on the individual... so what would you want, given that setup?

 

[Venom1956]

its not only the weight of the trigger but more so the length of the trigger pull. You'd be hard pressed to find a way to get a DA revolver trigger to travel all the way back by accident even if it is light. if it has a 20lbs trigger but needs to travel an 1/4" inch its alot more likely to discharge then 4lbs DA trigger with a normal travel.

 

[Snyper]

Let's say it's a 4.5 lb or less trigger weight on a DAO revolver that you have on hand.

A more realistic figure would be 2-3 times that amount.

The number you use is closer to a single action pull weight, or a typical hunting rifle

The odds of a double action weapon firing by accident are very near zero.

The trigger has to be pulled fully to the rear for the hammer to fall, and that won't happen unless a person holds the gun and applies the pressure intentionally

 

[Lee Enfield]

The premise is that the trigger weight on the DAO is intentionally made substantially less to SA weights.

Would a safety lever make sense in this setup, or is it still highly unlikely to discharge "accidentally"?

 

[MrBorland]

Let's say it's a 4.5 lb or less trigger weight on a DAO revolver that you have on hand. Say you're chasing feral hogs, or you're in the presence of a pack of wolves, or for self defense in a home invasion all within a 50 meter range (assuming no rifle or other firearm is handy), but you're concerned about accidentally discharging the revolver while running or when jostled in close quarters. Setting aside for a moment that it should rely upon the competence of the shooter to keep the finger off the trigger when not intending to fire... would a safety lever to keep a lighter/easier trigger pull in check makes sense here, or will the safety lever get in the way in the heat of the moment? I'm sure it depends on the individual... so what would you want, given that setup?

Right now, the most aggressively-tune revolvers have a DA trigger pull of about 5 1/2lbs. And those are competition DAO revolvers tuned by top gunsmiths, and will only shoot ammo that uses fully-seated Federal primers. Not exactly the gun for the scenarios you describe.

Secondly, the transfer bar and rebound slide act as internal safeties, but the transfer bar relies on the shooter keeping their finger off the trigger. Pulling it while running or jostled is a shooter error resulting in a negligent discharge, and might very well happen with a stock trigger pull. No safety will protect against unsafe gun handling skills.

 

[Lee Enfield]

The scenario would be for a hypothetical revolver with the given variables... if such a revolver were to be made, would you think a manual safety lever be implemented (i.e. would a manufacturer decide to add one, say, because the entire scope of skill, accidental scenarios need to be considered given the easier trigger pull, etc.)? Or, even with a lighter trigger pull (and assuming a "close" trigger distance), would you think it to be unnecessary?

 

[MrBorland]

You're asking 2 different questions: Would it be implemented? and Would it be necessary?

In the extremely unlikely event such a revolver were made and were actually functional, I think there's a chance it'd have an external safety. Not because it's functionally needed (it wouldn't be), but because the company's worried about liability and feels they need it to cover their butt.

 

[turkeestalker]

but because the company's worried about liability and feels they need it to cover their butt.

Exactly, a lawyer button so to speak. Would non-gun-owners who know little about firearms in general much less double action revolvers be all over the idea? Most likely yes, but only for their lack of knowledge and understanding.

You do bring up a good point in that being faced with a high stress self defense situation, would a person typically have the where with all to NOT put their finger on the trigger prior to being ready to fire? Probably not, honestly I don't think I'd refrain from having my finger at the ready myself. BUT, if there were some form of manual safety on such a revolver, I'd also have that disengaged at that point. Is that foolish? Maybe... but it's still the way I figure it would probably be for me, understanding that in such a situation nothing will be the way we think it may.
There was a study done by some law enforcement agency back I think in the late 90s that determined that the human hand can apply 25 lbs. of pressure just from a reaction to being startled, and that is not taking into account what stumbling or what not could cause as you suggested. I need to find that info and post a link.

I found where I read that, and I quote, " in 1991, the Federal Law Enforcement Training Center conducted a study that found the human hand was capable of convulsing suddenly and involuntarily with up to 25 pounds of pressure under a startle response". The article is a good one and may help with a bit of insight if anyone is interested in reading here is the link.

http://www.breachbangclear.com/a-critical-look-at-trigger-pull/

 

[michaelcj]

I believe Venom has the answer here.

I just now walked in from annual qualification for work.

S.W. Model 10 2" absolutely stock for weight of pull but bearing surfaces polished and machine turned. Probably a bit over 8.5 but smooth.

My old Davis PPC gun built on a SW 10 frame. 6" bull with full under lug and Aristocat Rib. Bobbed DA only hammer. Coil spring main. Over travel stop screw. This one is probably right at about 5 lbs.. Never had a fail to fire.
[took that one out for kicks and to freak out the young guys / gals]

Both are completely safe without any additional safety mechanism [except the operator].

Third gun is a 1911…. lots of redundant safeties there including the operator [as above].

Mike

 

[Snyper]

The scenario would be for a hypothetical revolver with the given variables..

Any answer is pointless speculation, since there's nothing realistic about the 'hypothetical revolver"

A safety won't stop fools from pulling triggers by mistake

 

[lee n. field]

Just curious about this... I understand that DA revolvers don't need a safety lever because of the heavier trigger pull that act as a "safety". It's also subjective depending on the individual's "feel" for the trigger weight, and the individual should have the greatest control over safety and the trigger. But, what if the trigger weight was reliably reduced... typically at what trigger weight threshold (range) would a safety lever be "necessary" (or, below what minimum trigger weight?)? Thanks in advance.

You'll never get that low, in a double action revolver. It would be unreliable before it would be unsafe. IMHO.

--"Lee N. Field", not to be confused with "Lee Enfield"

 

[wpsdlrg]

Bear in mind that there is one other aspect to revolver safety, while holstered, that hasn't been considered here. That is, the cylinder. In a holster or firmly seated in a pocket holster, etc. there is friction against the cylinder, thus making it much more difficult to turn.

Why does that matter ? Because, in order for a DA revolver to fire, three things have to happen simultaneously. The trigger must be pulled, the cylinder must turn (to the next chamber).....and the hammer must be cocked. Stop any of these from happening.....and NO bang. So, in most cases, a holstered revolver is "bound up" simply by the friction against the cylinder.....making an A.D. MUCH less likely (nearly impossible, with a proper holster fit).

 

[44 AMP]

typically at what trigger weight threshold (range) would a safety lever be "necessary" (or, below what minimum trigger weight?)? Thanks in advance.

I have an answer, but you aren't going to like it.
The only weight range were a safety is "necessary" is 0lbs (zero) and under, at which point the safety becomes the trigger.

Handy, useful, effective, even a "good idea" a safety can be all these things, but it is never necessary.

Two of the great lies (or myths, if you prefer) common in the modern era are that "safeties are necessary" and "safeties make the gun safe /are infallible".

Neither is true, and never has been.

(happy to discuss my reasoning, in detail, if you like.)

 

[DPris]

An un-answerable question, really.
It's not a matter of trigger weight that indicates a "need" for a safety & the DA revolver simply doesn't need one.
Denis

 

[Crankgrinder]

People who reduce da trigger weights as you describe don't use them for carry pieces. They are range toys or competition pieces if done so, an I believe there has already been mention of the reduction in its reliability that will inevitably take place before this level is reached. Da revolvers rely on spring energy to force the hammer down in order set it off. If this energy is insufficient, it doesn't go bang.

 

[Lee Enfield]

What's the lowest effective trigger pull weight on a DA you've seen?

 

[Driftwood Johnson]

What's the lowest effective trigger pull weight on a DA you've seen?

Howdy

I just put my super sophisticated trigger gauge (a digital fishing scale) on a few classic S&W 38 M&P revolvers. Most of them broke at about 10 -12 pounds. These are classic S&W double action revolvers, pretty much stock, just the way they would have been when carried by a policeman.

A few things about safeties and double action revolvers. First off, the trigger pull on a double action revolver is much longer than on a single action revolver. The trigger on a typical S&W K frame has to move back about 1/2" under about 10 pounds of force, before it trips the hammer. Not so with single action. Once the hammer is already cocked, it only travels a tiny bit, probably less than 1/32", and it usually only takes two or three pounds to trip it. Later on, I'll check the actual trigger pull needed on a K frame Smith.

Check out how far the trigger has moved in these two photos of a K frame Model 17-3. (Yes, with the modern short action, the distance the trigger travels before it trips is a bit less than it travels in single action full cock, but not all that much.) A Double Action Only Smith will be no different.

Now consider this. The Trigger Guard is called that for a very specific reason. It guards the trigger from inadvertently being pulled. Long ago, spur trigger revolvers were fairly common. These Tip Up Smiths are all from the 1860s and 1870s. The very first S&W revolver built in 1857 had a spur trigger. But these were all single action revolvers. In order to fire them, you had to first deliberately pull back the hammer. Let's not talk about dropping the gun, we are talking about misfires while it is in the hand.

For a long time, S&W was making Double Action revolvers that had no safety of any sort. Just like today, there was a trigger guard. Whether single action or double action, the trigger still had to be deliberately manipulated to fire the gun.

Starting in 1887 Smith and Wesson started building what they called the Safety Hammerless models. These were Double Action only models. There was no exposed hammer. And they incorporated a Grip Safety very similar to what is still on the Colt 1911. Here is a photo of a S&W 38 Safety Hammerless Third Model, made in 1896. The grip safety can clearly be seen at the rear of the grip. Just like with a 1911, when you hold the gun in your hand, the grip safety is automatically depressed and the gun can be fired. If the grip safety is not depressed, the trigger will not move and the gun cannot fire. Because of the squeezing motion that depressed the grip safety, these guns were often referred to as Lemon Squeezers. They were very popular and production of them did not cease until about 1940.

But frankly, by the time S&W started making side swing revolvers in 1896, they realized that a safety of any sort on a Double Action revolver was pointless. That is why there is no sort of safety on a modern Double Action revolver. It is pointless. You have to deliberately pull the trigger pretty far and pretty hard before the thing will fire.

I will add that there was one very unusual modern Double Action revolver that S&W put a safety onto. It was a special order of the Model 12 M&P built in 1966 for the French police. This revolver had a sliding safety mounted on the side plate on the right side of the gun. The safety looked pretty much like the normal thumb latch that is on the left side of all S&W revolvers. In this case, sliding the latch forward locked the gun, sliding it backwards unlocked it. For those who are familiar with S&W double action revolvers, I cannot imagine a more awkward arrangement. Operating it would have required holding the revolver in the left hand, while the latch was pulled back with the right hand. I will bet a donut that most of these things either had the safety removed, or it was simply never engaged.