location of cylinder bolt notches

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c.r.

Single-Sixer
Joined
Apr 23, 2008
Messages
436
It is quite obvious the GP-100 has the cylinder bolt locted quite a bit to the right in the frame. It appears this puts the cylinder bolt notches location more between the chambers, rather than directly over the chambers. This must contribute to the strength of the GP, while still allowing a reasonable sized cylinder.

Do the Security Six and Speed Six, have the cylinder bolt offset like the GP? Or is the bolt more centered in the frame resulting in the bolt notches being directly over the chambers?

Thank you,
C.R.
 

Driftwood Johnson

Blackhawk
Joined
Sep 25, 2007
Messages
699
Howdy

So do all the Ruger single action models. That was one of the early changes Ruger made when he first started making single action revolvers way back in the 1950s. He moved the notches off center from the centerline of the chambers. With a Colt Single Action Army there are only a few thousandths of metal between the bottom of the locking notch and the chamber. That is one of the weak points of the cylinder, sometimes when a cylinder bursts from an overcharge the fracture actually starts at the bottom of the locking notch, rather than the thin spot between chambers. Moving the notch allowed Ruger to leave more meat in that area.
 

Boxhead

Blackhawk
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Mar 28, 2004
Messages
846
All said, the real question is the off-set really necessary? I'd look more to the barrel diameter and frame size at the forcing cone...
 

c.r.

Single-Sixer
Joined
Apr 23, 2008
Messages
436
Boxhead":qtro4gms said:
All said, the real question is the off-set really necessary? I'd look more to the barrel diameter and frame size at the forcing cone...

Is your question specific to revolvers chambered in 357? I'm aware of the reputation that S&W mdls 19/66 have for cracks appearing at 6:00 on the forcing cone.

However, what about the 5 shot revolvers? Isn't the location of the cylinder notches the weak point and not the barrel/frame?.........so t5 shot cylinders are used because they allow the placement of the notches to fall in between the chamber. I'm not specifically talking about the linebaughs, but let's use 5 shot 45Colts for example.

I suppose what I'm thinking is the location of the notches may not be weak point when dealing with saami specs, but as higher pressures are generated, is it possible the location becomes more critical?

Good question, you have me thinking.

~c.r.
 

Driftwood Johnson

Blackhawk
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Sep 25, 2007
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699
You are talking separate issues. Ultimately, a revolver is only as strong as its cylinder. The cylinder is the pressure vessel. Issues like cracks in the forcing cone are a separate issue. If the cylinder blows up it does not matter how strong the forcing cone was.
 

c.r.

Single-Sixer
Joined
Apr 23, 2008
Messages
436
driftwood, I agree with what you've said.

I suppose my previous post was poorly worded/thought out.

trying to clarify my question..............is Boxhead's question directed at Ruger's design?

I now believe that is what he's stating is there may be weaker areas on this revolver (or similar revolvers) than the location of the bolt notches.

~c.r.
 

Bucks Owin

Hunter
Joined
Mar 22, 2004
Messages
3,190
Driftwood Johnson":242nix47 said:
You are talking separate issues. Ultimately, a revolver is only as strong as its cylinder. The cylinder is the pressure vessel. Issues like cracks in the forcing cone are a separate issue. If the cylinder blows up it does not matter how strong the forcing cone was.
Right on amigo. Here's John Linebaugh's "lesson" regarding the cylinder being the "weak link" and how problems start at the bolt notch. This is a part of his article on "High Pressure Loads": :arrow: "Some may argue that their charge of 296 will act the same no matter how it is compressed. And it is true that this powder and its brother H-110 work best under mild compression. But when we push our powder charge well into the bottom of the case and cork it with a slug too long and heavy for that caliber we are changing several things.

We change the "dwell time" - the time the sits in the chamber (after the powder is lit) before it starts to move. The more time taken here the sharper the pressure curve becomes. The reduced capacity limits the working area of the powder which means it has to try and do its normal amount of work in a less than normal space.

We also change the burning rate. With retarded bullet movement due to excess bullet weight the burning rate of the powder increases (it burns faster) generating more gases and vicious circle is created.

And we change (or "shift") the problem area to the gun. The quick pressure curve that now lasts longer than normal due to increased dwell time, and the faster burning rate which generates more gas and more pressure than normal, hits the gun in the cylinder right at the base of the bullet. I have seem many cracked and blown cylinders to prove the blowup starts in the bolt notch. The great part of the pressure is put on a small part of the cylinder, usually near the bolt notch. With a normal-type load of proper bullet weight, not seated too deeply in the case, the pressure curve should flow through the cylinder well into the barrel throat and frame.

For a moment think of your cylinder and barrel frame area as a stack of washers with chambers and bores through them. If pressure was exerted through the whole stack, say for nearly 2", wouldn't that be stronger and safer than trying to apply the same amount of pressure on only the first few washers?

Thousands of rounds of testing here has proven to us that gun life is better with safe heavy loads using slow powders than it is with light loads using fast powders. Case life agrees. The fast powders "hit" the gun very quickly and the slow powders "take up the slack" so to speak, slower and with less hammering effect.

I have measured one of my early .500's on a Ruger frame recently that I know for certain has had over 1000 Proof-Class loads and a few hundred maximum loads. I cannot measure or detect any movement or wear in the gun. All loads used H-110 or WW-296 powders".
 

Enigma

Buckeye
Joined
Apr 17, 2002
Messages
1,994
Boxhead":1lbivi7s said:
All said, the real question is the off-set really necessary? I'd look more to the barrel diameter and frame size at the forcing cone...

I'd say it was. Skeeter Skelton noted one incident where his slightly overzealous reloading very slightly bulged a Colt SAA cylinder in that location.
 

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