DAO conversion?
DAO conversion?
Now that I've got two P-64's I'm seriously considering converting one to DAO if that's possible. There was a thread a while back, that I can't find again, where someone was talking about filing the full cock notch off the hammer to convert the pistol to DAO. Is this safe to do? Will it work properly and safely in DAO mode? I'd buy a second hammer to do it with so I can keep the original hammer unmodified. My older P-64, circa 1968, has a very smooth DA trigger pull and at 30 feet I'm dead on with it shooting DA, but the SA pull is scary light. Since I'd like to use this pistol as a pocket gun I think going DAO makes a lot of sense. Thoughts and opinions are welcome.
DAO conversion?
That is an excellent idea and, on its face, the filing of the sear notch on the hammer should do the trick. You just need to make sure that the disconnector is always working - otherwise - you will turn it into a machine pistol, and that would be a very bad idea.
I always felt that the guns like Glock or Kahr have too light of a trigger pull to be really safe in a pocket, that is why I carry a Seecamp.
I always felt that the guns like Glock or Kahr have too light of a trigger pull to be really safe in a pocket, that is why I carry a Seecamp.
DAO conversion?
I was the one who did it (filed the single action notch off of the hammer). Yes. It worked.
As a safety measure I would load only two rounds for the first few tries. Fire ONE and then manually eject the other from the chamber and look for a dimple on the primer. Anything more than a very small dimple would be unacceptable to me. BTW, I would do this test first BEFORE you modify the pistol to establish a base line. Many pistols will leave a small dimple on the primer of the chambered round under normal circumstances.
As a safety measure I would load only two rounds for the first few tries. Fire ONE and then manually eject the other from the chamber and look for a dimple on the primer. Anything more than a very small dimple would be unacceptable to me. BTW, I would do this test first BEFORE you modify the pistol to establish a base line. Many pistols will leave a small dimple on the primer of the chambered round under normal circumstances.
Last edited by pshootr on August 1st, 2008, 11:55 pm, edited 1 time in total.
DAO conversion?
Thanks PshootR for posting. After looking closely at the P-64 I have to assume that with no full cock notch that the only thing preventing the gun from firing full auto once the full cock notch is gone is the hammer will not have the velocity to fire the second cartridge after riding the slide home.
The disconnector, if I understand it properly, disconnects the trigger group from the hammer once the slide moves rearward, preventing the hammer from dropping off the full cock notch if the trigger is held to the rear after firing. It seems to play no part at all once the full cock notch is gone.
I believe I will try this, but I also will take your advice and check for primer dimpling before I modify the gun. Although with the lightened Wolf 18 pound hammer spring, I'm not really expecting the hammer to have the force to fire the round if it rides the slide home. The last thing I want is an illegal weapon.
The disconnector, if I understand it properly, disconnects the trigger group from the hammer once the slide moves rearward, preventing the hammer from dropping off the full cock notch if the trigger is held to the rear after firing. It seems to play no part at all once the full cock notch is gone.
I believe I will try this, but I also will take your advice and check for primer dimpling before I modify the gun. Although with the lightened Wolf 18 pound hammer spring, I'm not really expecting the hammer to have the force to fire the round if it rides the slide home. The last thing I want is an illegal weapon.
Last edited by 3rdpig on August 2nd, 2008, 12:42 am, edited 1 time in total.
DAO conversion?
I think the P-64 would work the same as a Kel-Tec P-11 with this mod. To fire this way the firing pin would have to be welded to the breach face. That is how sub-machine guns which fire from an open bolt work.
DAO conversion?
I am no expert on modifications of this severity, but I wonder.....would the BATFE frown upon this sort of potentially dangerous modification?
I'm not a smith. My changes are limited to firing pins, springs, grips, etc, on several types of mil-surp stuff. I just wonder how far you can go before you do have an illegal weapon in your possesion, and not really even know it.
???
Fritzhund
I'm not a smith. My changes are limited to firing pins, springs, grips, etc, on several types of mil-surp stuff. I just wonder how far you can go before you do have an illegal weapon in your possesion, and not really even know it.
???
Fritzhund
"When the going gets weird, the weird turn pro"
Hunter S. Thompson: Fear and Loathing in Las Vegas
Hunter S. Thompson: Fear and Loathing in Las Vegas
DAO conversion?
Well I did the deed today. I first identified the full cock notch, then took 95% off with a belt sander, then took the rest off by hand with a 240 grit sandpaper and finished it up with 400.
I noticed one thing after reassembling the gun for the final time and doing a function test. When I pull the trigger and fire the gun in DA mode, if I hold the trigger back I can push the hammer forward, pushing the firing pin forward against it's spring. If I continue to hold the trigger back and rack the slide (and of course the hammer rides forward with the slide) I can't push the hammer forward and depress the firing pin, something is blocking it, until I release the trigger and pull it again. So there is firing pin block that only allows one strike of the firing pin per pull of the trigger. I expected there was, but couldn't visually ID it, couldn't find a detailed description of the fire control group and couldn't test it while the full cock notch was there.
This gun cannot fire full auto in DAO mode unless that mechanism fails AND the hammer has enough force to strike the firing pin hard enough to ignite the primer after riding the the slide forward, which I tend to doubt it does, specially with the lighter hammer spring.
That being said, I certainly will test it several times with only two rounds in the gun. Can't be too careful after making these kinds of modifications.
Fritzhund - I was concerned also about this as well, but since DAO guns that work in the exact same way are legal and sold every day, modifying a DA/SA gun to operate the same way should be legal as well, as long as the gun cannot fire full auto. Which I now believe this one cannot unless the firing pin block fails, even then I think it would be unlikely. But the BATFE are a law unto themselves, and they've stated that a failure of a double barrel shotgun that makes it fire both barrels at once makes you a criminal in possession of a full auto weapon. They've also shown that if they want you they'll just confiscate a weapon you own and modify it until they do get it to fire full auto.
I noticed one thing after reassembling the gun for the final time and doing a function test. When I pull the trigger and fire the gun in DA mode, if I hold the trigger back I can push the hammer forward, pushing the firing pin forward against it's spring. If I continue to hold the trigger back and rack the slide (and of course the hammer rides forward with the slide) I can't push the hammer forward and depress the firing pin, something is blocking it, until I release the trigger and pull it again. So there is firing pin block that only allows one strike of the firing pin per pull of the trigger. I expected there was, but couldn't visually ID it, couldn't find a detailed description of the fire control group and couldn't test it while the full cock notch was there.
This gun cannot fire full auto in DAO mode unless that mechanism fails AND the hammer has enough force to strike the firing pin hard enough to ignite the primer after riding the the slide forward, which I tend to doubt it does, specially with the lighter hammer spring.
That being said, I certainly will test it several times with only two rounds in the gun. Can't be too careful after making these kinds of modifications.
Fritzhund - I was concerned also about this as well, but since DAO guns that work in the exact same way are legal and sold every day, modifying a DA/SA gun to operate the same way should be legal as well, as long as the gun cannot fire full auto. Which I now believe this one cannot unless the firing pin block fails, even then I think it would be unlikely. But the BATFE are a law unto themselves, and they've stated that a failure of a double barrel shotgun that makes it fire both barrels at once makes you a criminal in possession of a full auto weapon. They've also shown that if they want you they'll just confiscate a weapon you own and modify it until they do get it to fire full auto.
Last edited by 3rdpig on August 3rd, 2008, 5:56 pm, edited 1 time in total.
DAO conversion?
3rdpig
That "something" that stops the hammer from falling on the firing pin before the trigger is released is disconnector - a part that you so quickly discounted in one of your posts above.
Disconnector in this pistol works with the trigger bar removing it from the hammer, with safety(it drops the hammer to a safe position when the safety is being engaged) and with the slide disconnecting the trigger/hammer group from enagagement until the slide is in its full forward (battery) position.
That was exactly why I cautioned you to make sure that it works correctly after your "modifications" - nothing less and nothing more.
That "something" that stops the hammer from falling on the firing pin before the trigger is released is disconnector - a part that you so quickly discounted in one of your posts above.
Disconnector in this pistol works with the trigger bar removing it from the hammer, with safety(it drops the hammer to a safe position when the safety is being engaged) and with the slide disconnecting the trigger/hammer group from enagagement until the slide is in its full forward (battery) position.
That was exactly why I cautioned you to make sure that it works correctly after your "modifications" - nothing less and nothing more.
DAO conversion?
...and by the way, any modifiactions that would make this a fully automatic pistol could land you in jail.
DAO conversion?
3rdpig 
It appears that you have done some research......
Wow, a fully automatic double barreled shotgun. 1 BOOM 2 BOOM
Then what happens???
Thanks for the update. I like to read about the obscure mods.
Fritzhund
It appears that you have done some research......
Wow, a fully automatic double barreled shotgun. 1 BOOM 2 BOOM
Then what happens???
Thanks for the update. I like to read about the obscure mods.
Fritzhund
"When the going gets weird, the weird turn pro"
Hunter S. Thompson: Fear and Loathing in Las Vegas
Hunter S. Thompson: Fear and Loathing in Las Vegas
DAO conversion?
3rdpig is right I believe. The P-64 uses a rebounding hammer, a safety notch on the hammer and a disconnector. When the hammer falls it goes all the way forward and then rebounds to a position where the sear will engage the hammer's safety notch after the disconnector releases the sear. The operation of the slide causes the disconnector to release the sear. If the disconnector sticks in the down position the gun won't fire. It would be impossible for the disconnector to stick in the up position unless someone ground off the top of the disconnector because the slide hits it and drives it down. If it refused to go down the slide would be unable to cycle.
DAO conversion?
Sorry not to have gotten back to this thread sooner, work reared it's ugly head.
I shot my DAO P-64 this morning and the DAO operation works fine. There is NO marks whatsoever on the primers of the rounds under the hammer after firing.
But, I'm back to getting light primer strikes. This was a problem I originally had with this gun before the DAO conversion with Wolf ammo. I solved the problem by going to Silver Bear ammo, even with the 18 pound hammer spring I only got 1 light strike in 50 rounds, which I considered to be acceptable. With DAO operation I'm getting one light strike per 6 rounds, which isn't acceptable at all. I've had several revolvers over the years that I've lightened up the hammer spring and gotten light strikes in DA mode but not in SA mode. So I think the problem existed before and is just excerbated because all shots are now DA instead of 1 out of 6.
The gun is clean and well lubricated. Unless there's a problem with the firing pin I'm thinking I just need to go to a heavier hammer spring, 20 or 22 pounds. I think I'll put the stock spring back in for now and see if the problem goes away, and if it does then I'll order a 20 and 22 pound spring and use the lightest that offers reliable ignition.
I shot the gun quite well at 11 yards, well enough to keep all rounds in the black on a B-12 reduced silhouette target. So besides the light strike problem I'm very happy with my DAO P-64, I think when I get the right hammer spring in place it will be an excellent pocket pistol.
I shot my DAO P-64 this morning and the DAO operation works fine. There is NO marks whatsoever on the primers of the rounds under the hammer after firing.
But, I'm back to getting light primer strikes. This was a problem I originally had with this gun before the DAO conversion with Wolf ammo. I solved the problem by going to Silver Bear ammo, even with the 18 pound hammer spring I only got 1 light strike in 50 rounds, which I considered to be acceptable. With DAO operation I'm getting one light strike per 6 rounds, which isn't acceptable at all. I've had several revolvers over the years that I've lightened up the hammer spring and gotten light strikes in DA mode but not in SA mode. So I think the problem existed before and is just excerbated because all shots are now DA instead of 1 out of 6.
The gun is clean and well lubricated. Unless there's a problem with the firing pin I'm thinking I just need to go to a heavier hammer spring, 20 or 22 pounds. I think I'll put the stock spring back in for now and see if the problem goes away, and if it does then I'll order a 20 and 22 pound spring and use the lightest that offers reliable ignition.
I shot the gun quite well at 11 yards, well enough to keep all rounds in the black on a B-12 reduced silhouette target. So besides the light strike problem I'm very happy with my DAO P-64, I think when I get the right hammer spring in place it will be an excellent pocket pistol.
DAO conversion?
It's expensive, but Cor-Bon uses very soft primers.
DAO conversion?
I put the factory hammer spring back in and shot it today. It functioned flawlessly. So now I know it works with the stock spring, which is 24 lbs according to Wolfe's site, but not with the 18 pound spring. I guess my only other option is the 20 lb spring....I wonder if that much of an increase is enough to make the difference? It sure is a heck of a lot harder to keep the rounds on target with the factory spring.
DAO conversion?
You can improve the P-64's double-action trigger pull by polishing the hammer strut and the area of the hammer between the safety notch and the full-cock notch. Do not touch either notch, just the curved area between them. If using the factory main spring rolling up a piece of sandpaper and polishing the inside of the coil spring may help a little too. If you want to remove the serrations in the trigger's face I have found the easiest way is to remove the trigger and clamp it face up in a vice and then use a standard size semi-round file to remove the serrations. The standard full size semi-round files have a semi-round side that just about exactly matches the curvature of any pivoting trigger I've ever had on a handgun. Of course, it wouldn't be any good on a sliding Colt 1911 style of trigger, but then I don't remove the serrations on those anyways.