Any ill effect firing DA/SA revolver in SA?
- Thread starter HankC1
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Darkstar888
New member
Absolutely not. Carry on.
Theoretically speaking, your firing pin probably won't last as long. The SA hammer strike is actually quite a bit harder than the DA hammer strike.
The key word is theoretically. Firing pins do occasionally break in modern revolvers, but it's not something that I would worry about.
The key word is theoretically. Firing pins do occasionally break in modern revolvers, but it's not something that I would worry about.
shootniron
New member
Some folks just have to be different.
Jim Watson
New member
For a lot of years, target shooters went SA with their K38s and Officer's Model Target double action revolvers. Didn't hurt them a bit.
Jim Watson
New member
By me, for one.
If I tinker with a revolver, I test it with CCI primers in slow double action. This will expose unreliably weak springs that perform ok in single action and with other brands of primer.
If I tinker with a revolver, I test it with CCI primers in slow double action. This will expose unreliably weak springs that perform ok in single action and with other brands of primer.
Hahaha, this does NOT need a citation, this can easily be seen by the naked eye. Single action very easily throws a far, FAR heavier hit than double action, especially with a S&W revolver. Beyond obvious.
If you run in to Jerry Miculek, he will "cite" it for any non-believers.
Sheesh... a citation... really.
If you run in to Jerry Miculek, he will "cite" it for any non-believers.
Sheesh... a citation... really.
springer99
New member
If the hammer strike is much more powerful in SA than in DA, will that give you any increase in muzzle velocity?
No, you won't hurt your revolver by cocking the hammer and a firing SA. Most folks I know don't do that except when hunting or shooting long range silhouette though.
No, you won't hurt your revolver by cocking the hammer and a firing SA. Most folks I know don't do that except when hunting or shooting long range silhouette though.
The difference isn't in the spring, it's in the different amount that the spring is compressed in SA vs. in DA.
Experimentation/observation will show that the hammer drops from farther back (more spring compression) in SA than in DA. Usually it's not difficult to see the difference. That would indicate more spring compression which means a harder strike.
One can also construct an experiment to observe the difference in the strength of the firing pin strike by using an object such as a short section of brass rod that will easily fit down the bore but is fairly close to bore diameter. You want it to be big enough that the firing pin will hit it when it's in the chamber but not so large that it binds or catches on anything.
Cock the hammer and drop the rod down the bore. When it's against the breechface, point the revolver upwards and pull the trigger. Measure the height that the rod jumps out of the bore. Do this several times and take the average height.
Now repeat the test, but this time, pull the DA trigger until the cylinder locks in place and hold it there. Then drop the rod down the bore and finish the trigger pull. Repeat this several times and take the average height.
Compare the average heights.
With my GP100, there's very little difference but I have one DA/SA autopistol where the rod jumps nearly twice as high with the SA pull as the DA pull.
I want to re-emphasize the word "theoretical" in my previous post. There's a difference in how hard the hammer hits the firing pin and it's measurable in some cases, but IMO it's not a practical concern--just an interesting factoid.
Strafer Gott
New member
Double action puts more strain on the firearm. The alloy double actions are worn out and long gone, but I still have the single actions.
This discussion actually brings up a related subject... one of shaving off hammer spurs and turning a stock revolver in to a "double action only" revolver. (And for the nit-pickers in the audience, I simply mean removing the spur and not actually altering the notches in the hammer internally and wholly removing even the physical ability to cock it without a spur.)
On one hand... removing the spur removes mass from the hammer. With the same exact mainspring pushing that hammer (now of less mass), that hammer should (will!) speed up as it's now of slightly less weight.
You can come up with a mathematical formula regarding the energy and how it has changed, but that result seems to me as though it might be equivalent or at least loosely related to the discussions we have about external ballistics and bullet energy. We know that the formula for energy seems to favor velocity over weight and we also (somewhat!) know that it simply does not always equate to better terminal performance. The easy example is a .223 vs .45-70 against an attacking bear... when you compare energy you can make an argument for similarity, but even a casual observer can guess the better real-world choice no matter what the energy numbers tell us.
So when you shave the spur off the hammer of a double action revolver and you do not change the mainspring, that hammer falls FASTER. But does it hit HARDER? I believe that it does not... but typically, not so much that it makes a difference.
But it can be an interesting discussion.
On one hand... removing the spur removes mass from the hammer. With the same exact mainspring pushing that hammer (now of less mass), that hammer should (will!) speed up as it's now of slightly less weight.
You can come up with a mathematical formula regarding the energy and how it has changed, but that result seems to me as though it might be equivalent or at least loosely related to the discussions we have about external ballistics and bullet energy. We know that the formula for energy seems to favor velocity over weight and we also (somewhat!) know that it simply does not always equate to better terminal performance. The easy example is a .223 vs .45-70 against an attacking bear... when you compare energy you can make an argument for similarity, but even a casual observer can guess the better real-world choice no matter what the energy numbers tell us.
So when you shave the spur off the hammer of a double action revolver and you do not change the mainspring, that hammer falls FASTER. But does it hit HARDER? I believe that it does not... but typically, not so much that it makes a difference.
But it can be an interesting discussion.
Are you saying that you had two revolvers that were identical for practical purposes but one was shot in DA while the other was shot in SA and the one shot in DA wore out first? That would be strong evidence that the DA was harder on the gun, especially if one could document similar usage (round counts) for each gun.
Or are you saying that you had two different revolvers where one was an SA only and the other was a DA/SA or DAO and the DA/SA wore out first? That would be harder to interpret as the difference might be that the DA/SA design was simply not nearly as sturdy as the SA only design. That wouldn't be particularly surprising as SA designs tend to be much simpler than the DA/SA revolvers and don't require design features like sideplates which make the overall design weaker.
What typically broke on the revolvers you wore out?
Or are you saying that you had two different revolvers where one was an SA only and the other was a DA/SA or DAO and the DA/SA wore out first? That would be harder to interpret as the difference might be that the DA/SA design was simply not nearly as sturdy as the SA only design. That wouldn't be particularly surprising as SA designs tend to be much simpler than the DA/SA revolvers and don't require design features like sideplates which make the overall design weaker.
What typically broke on the revolvers you wore out?