Roger GP100, what prevents cylinder forward movement when cylinder open?

[Rmiked]

I was watching a Utube on the GP100 discussing cylinder forward movement. The guy preferred to use speedloaders with left hand. When speed loading, since he didn’t have right index finger supporting the front of the cylinder, he would push the cylinder forward (down) with speed loader and it would bind on frame when trying to close the cylinder necessitating pushing it back toward hammer end of gun, slowing his reload times. What is the design feature that prevents forward movement of the cylinder when it is in the open position? I’m guessing the trigger assembly has an interfacing hook or notch that catches the lower cylinder shaft that slides in the frame. When the trigger assembly is installed it appears you can’t remove the cylinder assembly for the frame. Does anyone know? Thanks

[Rmiked]

Update: I watched a disassembly Utube on GP100. There is a hemispherical looking ball detent, staked in to the front of trigger assembly. It rides in a slot milled in to the lower cylinder shaft. Since you remove the trigger group down, before removing the cylinder assembly, it allows free forward movement of the cylinder assembly. I’m guessing there is a spring under that hemispherical ball decent because with the cylinder open, you can push it forward and it returns back toward hammer direction on its own. The disassembly Utube did not remove the ball so I couldn’t see a spring under it. A parts diagram for the GP100 calls it a “crane pivot lock plunger” with an associated “crane pivot lock spring”.

[Crazy Dane]

Link to vid because something sounds fubar. None of my Rugers have any forward movement that would cause it to bind up. I have my 3 inch on my desk now and what movement if any is imperceivable.

[Rick R]

I had to get my 3” WC out of the safe and give it a look see.

If you push hard enough the cylinder and crane will move forward slightly obviously against an internal spring loaded detent. Once pressure is removed the assembly immediately moves back. I had to hold the grip and shove my thumb against the star to get it to move at all. Way more pressure than required to use any speedloader I’ve ever seen. While in the forward position the cylinder will still rotate.

I sounds like the gun in the video you watched may need a trip back to the mothership.

[Rmiked]

He did send it back. And he changed his method of reloading using his right hand, which for him was slower. I’m trying to find the Utube again as I stumbled upon it. It was about 18 minutes long. He basically discussed several things he modified about his gun and use. A front sight fiber optic, comparing metal speedloaders requiring push down to release to plastic speedloaders requiring pinching motion to release cartridges. Roger tightened up the play issue and he thinks if he uses the push method speedloader it will get loose again. That’s why I wanted to know what the design feature is that prevents that forward movement. Perhaps the hemispherical ball detent on his gun was mis-shaped allowing more play? Ruger service was excellent according to him and they polished up his pistol real nice. It was not a stainless pistol, blued finish.

[Hizzie]

My Novak SP101 did that. Sent it back and they replaced the whole trigger guard assembly as it was out of spec. It has not happened since. Twisty speedloaders are the devil.

[Rmiked]

I found the link: https://youtu.be/H7cUV4q0tMU

[vtfarmer]

He did send it back. And he changed his method of reloading using his right hand, which for him was slower. I’m trying to find the Utube again as I stumbled upon it. It was about 18 minutes long. He basically discussed several things he modified about his gun and use. A front sight fiber optic, comparing metal speedloaders requiring push down to release to plastic speedloaders requiring pinching motion to release cartridges. Roger tightened up the play issue and he thinks if he uses the push method speedloader it will get loose again. That’s why I wanted to know what the design feature is that prevents that forward movement. Perhaps the hemispherical ball detent on his gun was mis-shaped allowing more play? Ruger service was excellent according to him and they polished up his pistol real nice. It was not a stainless pistol, blued finish.

What you call the ball detent is listed in the owners' manual as Crane Pivot Lock Plunger. Underneath it is the Crane Pivot Lock Spring. The spring pushes the plunger outward to keep the cylinder back (toward the grip). If the spring breaks, or collapses, it doesn't exert enough force on the plunger to push the cylinder back to its' proper position. I have a SP101 that does the same thing if I push hard when using a speed loader. The plunger and spring are staked in position, so it's a factory repair job. So far it hasn't bothered me enough to send it back. Springs can go bad. A few years ago, speedloading my 5" GP100 on the range, I gave the ejector rod a whack with my hand and collapsed the ejector spring. I picked up a used spring on Gun Parts and replaced that one myself.

[jtcarm]

I’m a weak-hand (left) reloadee but the only GP I run in competition is a 10mm with moons.

I have worn out an S&W crane that went back for replacement. It developed a divot in the yoke and would slip forward about 1/8” on a reload and have to be pushed back to close the cylinder.

It could have been fixed by a good gunsmith who knows how to peen it back flat, but I guess those are getting hard to find.

[Rmiked]

What you call the ball detent is listed in the owners' manual as Crane Pivot Lock Plunger. Underneath it is the Crane Pivot Lock Spring. The spring pushes the plunger outward to keep the cylinder back (toward the grip). If the spring breaks, or collapses, it doesn't exert enough force on the plunger to push the cylinder back to its' proper position. I have a SP101 that does the same thing if I push hard when using a speed loader. The plunger and spring are staked in position, so it's a factory repair job. So far it hasn't bothered me enough to send it back. Springs can go bad. A few years ago, speedloading my 5" GP100 on the range, I gave the ejector rod a whack with my hand and collapsed the ejector spring. I picked up a used spring on Gun Parts and replaced that one myself.

Was the repair of that staked part difficult to do yourself?

My mistake. You replaced the ejector spring, not the Crane Pivot Lock spring. Watching the repair videos, that ejector spring does not look difficult to replace.

I still am curious how hard it would be to replace Crane Pivot Lock spring?