sizing cylinder throats

[mehavey]

...curious if it would take alot longer to wear out throats.

You're not going to wear down throat surfaces using cast lead -- of pretty much any hardness.

[fredj338]

Pin gauges are the way to go if you are starting in this. I bought a set of Starrett expandable hole gauges in 1969 and with a good Starett micrometer have been measuring the inside diameter of any hole since that time with these. Take a little time to get the feel for these, but then giver very accurate results.

^^THIS^^ I bought a set of pin gages, pretty cheap. It lets me quicky measure any ID accurately. IMO, a must for revo cast bullet shooters.

[Three44s]

Could you explain in threads are cut in separate operations?

The two components involved in a thread crush condition are the barrel and the frame. They are machined separately by necessity, likely by different machinists. Assembly is likely performed by a third person.

Three44s

[castmiester]

The two components involved in a thread crush condition are the barrel and the frame. They are machined separately by necessity, likely by different machinists. Assembly is likely performed by a third person.

Three44s

thread crush barrel and frame.. that is a given. Machined separately..... what for ?

[Tatume]

thread crush barrel and frame.. that is a given. Machined separately..... what for ?

I suppose it is possible to machine a frame and barrel from one piece of steel, but it would be cost prohibitive to do so.

[DougGuy]

With a Ruger, they calculate how much "interference" fit they need to torque the barrel so the front sight (which is already installed on the barrel) is rotated up to 12:00 when it reaches the specified torque.

If the gun shoots to the left, they torque the barrel some more so it moves the sight blade to the left, this makes the barrel point more to the right. Here is where it gets thread choked.

You really don't need to worry about thread choke in a .357 because the barrel stub (the threaded portion of the barrel that screws into the frame) is much thicker than a 44 or 45 caliber barrel.

45 Colt barrels are the worst ones for thread choke because the barrel walls at the threaded stub are thinner than any other caliber they produce on a single action frame and torquing the barrel distorts the inner bore easier, creating choke as they tighten.

[castmiester]

With a Ruger, they calculate how much "interference" fit they need to torque the barrel so the front sight (which is already installed on the barrel) is rotated up to 12:00 when it reaches the specified torque.

If the gun shoots to the left, they torque the barrel some more so it moves the sight blade to the left, this makes the barrel point more to the right. Here is where it gets thread choked.

You really don't need to worry about thread choke in a .357 because the barrel stub (the threaded portion of the barrel that screws into the frame) is much thicker than a 44 or 45 caliber barrel.

45 Colt barrels are the worst ones for thread choke because the barrel walls at the threaded stub are thinner than any other caliber they produce on a single action frame and torquing the barrel distorts the inner bore easier, creating choke as they tighten.

Thanks for the clarification Doug ! Guess the frame is harder than the barrel according to your explanation ?