Cylinder stop notch lead-in ?

[Tampa-XD45]

The screen print below is from David Olhasso's website.  What does the highlighted service accomplish?

 

 

[Fishbreath]

I believe it reduces the chance of skipping a chamber when pulling the trigger fast—deeper lead-in cuts give the cylinder stop more time to start moving, and less distance to travel when it reaches a notch.

[Bill Sahlberg]

I have never had any issues with my 627s 38/357 but David is stating specifically the 929s 9MM which have many MIM parts that the early 627s didn't have.

[Bill Sahlberg]

I have never had any issues with my 627s 38/357 but David is stating specifically the 929s 9MM which have many MIM parts that the early 627s didn't have.

[revoman]

This was done to my revolvers a long time ago by Mark Hartshorne with Pinnacle Custom and I have never had problems with the notches getting peened and that was the reason I had him do that on his recommendation.  One less thing to worry about. 
Oh and the reason I had it done in the first place is I was at a match in Wisconsin and it happened and the rest of the match went downhill quick. 

[Tampa-XD45]

1 hour ago, revoman said:

This was done to my revolvers a long time ago by Mark Hartshorne with Pinnacle Custom and I have never had problems with the notches getting peened and that was the reason I had him do that on his recommendation.  One less thing to worry about. 
Oh and the reason I had it done in the first place is I was at a match in Wisconsin and it happened and the rest of the match went downhill quick. 

Can you post a picture of one of the notches that was modified?

[revoman]

When I get home I can but basically he centered the entrance into the notch and then cut the entrance and notch just a minute deeper. I doubt if pictures will show it. One way to see if the cylinder stop is lined up to the center of the notch is to look at the marks on your cylinder and if they are not centered going into the cylinder ramp(that is not what it is called I just don’t know the name) before it enters the notch itself the it is not aligned properly. That is how it was explained to me. 

[testosterone]

22 hours ago, Tampa-XD45 said:

The screen print below is from David Olhasso's website.  What does the highlighted service accomplish?

 

 

i can take a picture a little later, the scallop cut is increased pretty dramatically.

As jay said, this is a modification made to alleviate chamber skipping.

Personally, every single n frame I have ever owned developed chamber skipping sometime in the first 10-20k trigger pulls, some much faster, like a 625 flaking out after less than a 1000 rounds 3 stages into area7 and I was actually not a thousand miles behind lentz for once...

Dave has commented that nobody is as abusive to the guns as I am, but I think i'm partially just unlucky.

[testosterone]

On 1/24/2023 at 11:22 AM, Tampa-XD45 said:

The screen print below is from David Olhasso's website.  What does the highlighted service accomplish?

 

 

 

 

 

with and without, as you can see this is not a slight adjustment, its a significant cut.   the image looked more focused on the phone, but if you look at the factory cut, you can see how the lead in runs and how the final resting spot is not centered on the notch(before of after), but the wider/deeper notch makes it less abrupt.

 

 

Edited January 25, 2023 by testosterone

[testosterone]

23 hours ago, Bill Sahlberg said:

I have never had any issues with my 627s 38/357 but David is stating specifically the 929s 9MM which have many MIM parts that the early 627s didn't have.

 

One of the theoretical improvements that I think started on the 929's is the cylinder stop has an angle on it that is something close to the ball cut, this way its not riding in on the trailing side before dropping in.  most of the parts are mim though which is not "bad" on its face necessarily, I think i've seen some arguments from prominent gunsmiths that they can be better from a consistency point of view.

[Tampa-XD45]

On 1/25/2023 at 12:14 PM, testosterone said:

 

 

 

with and without, as you can see this is not a slight adjustment, its a significant cut.   the image looked more focused on the phone, but if you look at the factory cut, you can see how the lead in runs and how the final resting spot is not centered on the notch(before of after), but the wider/deeper notch makes it less abrupt.

 

 

Thanks for the picture.  Neither of my R8 cylinders lead-ins are centered.