Single or Double action pistol

Posts related to handguns (pistols, revolvers)
aadhaulya
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Re: Single or Double action pistol

Post by aadhaulya » Thu May 14, 2015 8:16 pm

Armed Defence wrote: @aadhaulya. :D My prayers are with NAGRI and all the gun right activists in India. I hope one day you people will be successful in getting the laws relaxed.
(y)

Today I read about a massacre in Karanchi. Hope all is well with you and your family.

Regards

Atul

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xl_target
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Re: Single or Double action pistol

Post by xl_target » Thu May 14, 2015 9:43 pm

CZ call it a "Safety Stop" but in at least one other place, they call it a "half cock safety notch".

Here is the operators manual for the RAMI.
It should answer all your questions about the operation of the pistol.
http://cz-usa.com/hammer/wp-content/upl ... 075_en.pdf
“Never give in, never give in, never; never; never; never – in nothing, great or small, large or petty – never give in except to convictions of honor and good sense” — Winston Churchill, Oct 29, 1941

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Re: Single or Double action pistol

Post by TwoRivers » Thu May 14, 2015 10:50 pm

The older hammer guns typically had two sear notches in the hammer, the first one with very deep engagement, making it almost (because it or the sear nose could break) impossible to pull the trigger to drop the hammer, this is the half-cocked position. The half-cock position served as safety. The second notch, or full-cock, is much shallower and allows pulling the trigger to drop the hammer.

A de-cocker is more involved, and does not rely on, or need a half-cock notch in the hammer, but uses a firing pin block to positively prevent the pin from reaching the primer, even if you were to drop the gun on its hammer. It does not simply drop the hammer to half-cock.

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Re: Single or Double action pistol

Post by timmy » Fri May 15, 2015 4:47 am

Half cock:

Please study this picture of a hammer from a Colt Single Action Army (the "six gun" featured in Western movies).

Image

The larger hole near the center of the base of the hammer is the pivot for the hammer.

The hole near the bottom of the base of the hammer is where the "hand" mounts. This is the part that pushes up to turn the cylinder when the hammer is cocked.

Near the hand hole in the base, you will see a small step. This is the full cock notch and the sear end of the trigger will rest here and hold the hammer in the cocked position when the hammer is pulled back far enough. Pulling the trigger will move the sear end out of the notch and allow the hammer to fall under the power of the mainspring.

You can see how dropping a heavy gun, which lands on the cocked hammer, could easily break off this step or the thin sear end of the trigger that engages it, firing the gun. This is why I say that the hammer must be positively blocked, not just the trigger or sear, for the gun to be safely carried when cocked. The full cock notch is too small, and so is the part that engages it, to make blocking the trigger an effective safety.

Now, move up the base of the hammer and you will see the half cock notch. You will see that it has a projection from it, so that the sear end of the trigger that engages it cannot be pulled. But this is not meant as a safety. It's purpose was to allow the hammer to be pulled half way back, so that the cylinder lock is released. The cylinder is locked when the hammer is fully cocked and when it is not cocked, so the cylinder will not rotate.

As the hammer is pulled back, the cylinder is unlocked so that it can rotate to the next chamber to be aligned with the barrel for the next shot. When the revolver is loaded, the cylinder has to be rotated to load the chambers. So, the hammer is placed in the half cook position and the cylinder can be rotated for loading.

If the gun was carried half cocked, it is possible for a brush branch or piece of clothing to pull the hammer back from the half cock notch and then release it before it was all the way cocked, and for the hammer to fall past the half cock notch and fire before the trigger could re-engage the half cock notch.

Half cock waS used during the old flintlock days and also the percussion cap days for loading. For both of these guns, the hammer was pulled back to half cock to reload these guns from the muzzle, and then the hammer was pulled fully back to fire. Leaving the hammer on half cock on a muzzle loader is the basis for the saying, "going off half cocked," meaning going off to do a talk before one is completely ready or prepared.

Half cock notches have persisted in firearm design for many years past their usefulness. Don't make the mistake of thinking that they can function as a safety.
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Re: Single or Double action pistol

Post by AgentDoubleS » Fri May 15, 2015 10:13 am

Timmy, it is a treat to read your detailed posts, i read them many times over; thank for the trouble you take to share your knowledge.

timmy wrote:This problem rules out many older semi auto pistols for self defense, because who wants to take the time to rack the slide to load the pistol when a self defense situation arises?
The only..and only! reason i opted for the IOF revolver instead of the pistol.

Cheers,
SS

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Re: Single or Double action pistol

Post by aadhaulya » Fri May 15, 2015 11:01 am

SS wrote:The only..and only! reason i opted for the IOF revolver instead of the pistol.

Cheers,
SS
After going through a lot of posts on the topic of self defense I have realized that no body on this forum or any one I know had the urgent need to start firing away. So I guess it is a personal choice between a revolver and pistol. I own a revolver but always wanted a pistol. Right now I am short on funds but soon I will get rid of the revolver and buy the IOF pistol.
The only reason for buying a pistol is that I find shooting a pistol more romantic :D :D
Though, look wise the revolver seems more appealing.

Regards

Atul

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timmy
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Re: Single or Double action pistol

Post by timmy » Sat May 16, 2015 3:57 am

SS, thank you for your kind remarks.

IFG is the best gun board anywhere, and I'm privileged to share fellowship here. One only needs to look at airgun_novice's and Brihaji's event posts of members to see what a fine group of people congregate here. We have stories by folks like yourself and Prashantji and experts on knives like Moin.

Being part of what goes on here is a great experience, and contributing a bit is a real honor.
SS wrote:
timmy wrote:This problem rules out many older semi auto pistols for self defense, because who wants to take the time to rack the slide to load the pistol when a self defense situation arises?
The only..and only! reason i opted for the IOF revolver instead of the pistol.
Yes, you have made the same decision I would have made. Both types have their advantages, but given the availability of guns and ammo, your logic makes lots of sense.

Besides, who would argue with the opinion of someone who drives what you drive? :-)
“Fanaticism consists of redoubling your efforts when you have forgotten your aim.”

saying in the British Royal Navy

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Re: Single or Double action pistol

Post by AgentDoubleS » Sat May 16, 2015 10:28 am

timmy wrote:
IFG is the best gun board anywhere, and I'm privileged to share fellowship here. One only needs to look at airgun_novice's and Brihaji's event posts of members to see what a fine group of people congregate here. We have stories by folks like yourself and Prashantji and experts on knives like Moin.

Being part of what goes on here is a great experience, and contributing a bit is a real honor.
I second that, Tim. It's a great forum to be on. Thanks to members like xl_target, tworivers,mundaire, GBM, Vikram, Grumpy and yourself who add a wealth of technical and legal knowledge to an otherwise firearm experience and knowledge starved populace like myself. I am sure i have missed many names. May this tribe continue to flourish!
timmy wrote: Besides, who would argue with the opinion of someone who drives what you drive? :-)
:D :D let me be immodest and say, Touche! :D
This reminds me, my wife and i just rode to Corbett land- Nainital, kaladhungi et al. Will post a few pics on motorcycle thread.

Cheers,
SS

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timmy
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Re: Single or Double action pistol

Post by timmy » Sat May 16, 2015 7:35 pm

SS wrote:This reminds me, my wife and i just rode to Corbett land- Nainital, kaladhungi et al. Will post a few pics on motorcycle thread.
I can't wait for that treat!
“Fanaticism consists of redoubling your efforts when you have forgotten your aim.”

saying in the British Royal Navy

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Re: Single or Double action pistol

Post by Armed Defence » Sat May 16, 2015 11:25 pm

@aadhaulya. Thanks for inquiring. My family is safe and sound.

@xl_target. Thanks dear, but the owner's manual is for the manual safety version of RAMI. I can't find one for the decocker version. Please share if you find it

@Two Rivers. Thanks bro

@Timmy. Thank you very much for taking the time for writing such details. All the other friends over here have said that carrying a RAMI decocked with the decocker is safe and there is nothing wrong in it. So, I want you too to endorse this statement. Of course, I will excercise full care while doing it, like carrying in a good holster, etc. Basically, the problem is that, in Pakistan, and I think in India also, carrying a loaded pistol is very uncommon, unlike USA. And when it comes to carrying a loaded pistol without the manual safety and just with a decocker, people would call you a careless fool. But I don't want to blindly follow others. When one is carrying for self-defense, one needs to carry it loaded

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xl_target
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Re: Single or Double action pistol

Post by xl_target » Sun May 17, 2015 9:56 am

And when it comes to carrying a loaded pistol without the manual safety and just with a decocker, people would call you a careless fool. But I don't want to blindly follow others. When one is carrying for self-defense, one needs to carry it loaded
People can call you whatever they want. In fact, throughout life, people will probably call you many things.
That doesn't make it true.
As for the ones who tell you that carrying a RAMI decocked and loaded is foolish, I have one word for them; ignorant.
They don't understand how a CZ75 decocker type works.

First lets see how your RAMI works. It is not magic and it is not Rocket Science by any means.
When the hammer is cocked on the loaded pistol, pulling the trigger releases the hammer. This causes the hammer to fall under spring tension and to hit the back of the firing pin. This causes the firing pin to be driven forward and to indent the primer of the cartridge. This in turn ignites the propellant, creating gasses under high pressure which forces the bullet out of the barrel. If the firing pin cannot contact the primer, the cartridge cannot fire.

The CZ75 use a very simple mechanism to prevent the above. Because of the firing pin block, the firing pin cannot contact the primer of a loaded round.... unless the trigger is all the way back.

Don't take my word for it, try it yourself. Take the slide off the pistol and use something to push the back of the firing pin in. You will see that it will not protrude from the hole in the "bolt face". Now push in the spring loaded firing pin block and then push the firing pin forward. You will see that it now protrudes from the bolt face. Only when the trigger is all the way back does the firing pin block get pushed out of the way. The firing pin block is steel and while it is in place, you will have to crush it to get the firing pin to move. Keep in mind also that once the pistol is decocked, you now have a heavier and longer trigger pull to fire the pistol. Once fired (as the hammer is now cocked by the action of the recoiling slide), subsequent shots are in the single action mode, with a shorter lighter trigger pull. Hence the DA/SA designation for the action type. With this type of mechanism, as long as the pistol is mechanically functional, if you keep your finger off the trigger, it is not possible for it to fire.

Image
This is a SIG slide but your firing block is in a similar position on your RAMI.
SIG calls it a firing pin safety lock but it functions the same way as your RAMI firing pin block does.

http://cz-usa.com/hammer/wp-content/upl ... z75_en.pdf
Here is the generic CZ75 operators manual.
Look on the top of page 23 where they address decocking pistols equipped with a decocker.
Decocking
Serves for the lowering of the hammer from the cocked position to the hammer safety
notch position. There is no necessity to manipulate the trigger and hammer manually. This
device is especially useful when a cartridge is loaded in the chamber. In this state, when the
hammer is decocked, the pistol is safe for all normal handling and yet is ready for immediate use.
The above is a quote from the factory CZ75 manual.
Is the factory's word good enough for you?

You can ask Tim to endorse whatever you want, it doesn't mean a thing. As far as you know he's just a guy on the Internet.
Besides that Tim doesn't own and carry a CZ75 decocker equipped pistol: I do but I'm just another guy on the Internet.
You should investigate and learn how your firearms function, for yourself. Don't take the word of a guy on the Internet.
“Never give in, never give in, never; never; never; never – in nothing, great or small, large or petty – never give in except to convictions of honor and good sense” — Winston Churchill, Oct 29, 1941

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Re: Single or Double action pistol

Post by timmy » Mon May 18, 2015 12:03 am

Armed Defence:

1. I do endorse what XL is saying -- including what he says about me and about himself

2. He is correct in telling you that I don't have a CZ75, so I don't have the same perspective on your question that he does.

3. I would have responded to your question, had XL not responded, by telling you that I'm not hands-on familiar with a CZ75 and that you should listen to what he says.

4. Furthermore, I would have pointed out what XL did: there is no substitute for knowing how your gun -- any gun you have or might buy -- works. It is well and good to listen to other opinions, and it is also well and good to separate the sources of those opinions into more and less helpful categories. But XL's principle here should hold as an iron and golden rule on these forums: each of us has to take ultimate responsibility for our own safety and the safety of those around us, when we handle guns.

It is also all well and good to align yourself with those who you respect. But those folks will not be around if you blow your foot off, or worse. No matter how respectable someone may be, they can still be wrong. And no matter how closely you align yourself with someone you respect, you can still misunderstand them.

When it comes to a bullet flying through the air, relying on what I said above is not sufficient. You must also know of your own knowledge what makes things tick in your firearm.

This is not to say that even you, with every kind of learning, can make yourself infallible. There is wisdom to be found in many counsellors, it is said, and checking your own knowledge with others you know to be knowledgable is a wise thing to do.

Regarding XL, he is a very sharp individual. He's had a lot of experience with guns. So if you read the last two sentences of his post, that is even more reason to listen to him.

Read his post carefully, and test it out for yourself.

It would be very flattering to accept your kind words and tell you "thus, it is so," but here at IFG, we would like to encourage a love of firearms based on knowledge, not on the personality of ourselves or others.

That said, you should always feel welcome to ask about something and to offer your own opinion here! :-) Those who love guns and those who want to learn about them are the sort of folks who are good at telling their friends and neighbors what is fun and safe and enjoyable about legal gun ownership, which is what we stand for.

PS, yes, I can say that I know XL. He is a good man and he has your gun interests at heart.
“Fanaticism consists of redoubling your efforts when you have forgotten your aim.”

saying in the British Royal Navy

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Re: Single or Double action pistol

Post by Armed Defence » Tue May 19, 2015 10:11 pm

@xl-target. Thanks for the detailed reply and the CZ 75 manual. Actually, the thing is that I don't have enough experience with firearms to understand their mechanism by opening them. So, I was trying to find answer to my question on the internet. I found conflicting views by people on different websites. Here on IFG, I got the chance to ask this question from you people, living in USA, as Americans know a lot about guns because of the relaxed gun ownership laws. I am happy that I am satisfied now. And thanks for the advice about knowing one's guns. Only a well wisher gives such advice :D

@Timmy. Thank you very much. As said above, my interest in guns is new and I haven't even practiced enough to start carrying a loaded pistol. I am gathering knowledge about the gun present in my home, because it will ultimately benefit me.

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Re: Single or Double action pistol

Post by timmy » Wed May 20, 2015 2:36 am

Armed Defence, you are choosing the path of learning and practice, which is wise. I know your involvement with firearms will be enjoyable and rewarding because of your choices!
“Fanaticism consists of redoubling your efforts when you have forgotten your aim.”

saying in the British Royal Navy

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