Purpose of Recutting Crown?

[Axel Yup]

I am looking to have some work done to a S&W J-frame. Teddy Jacobson offers an option called "recut crown 45 degrees and polish bore."

What does this work entail and how does it help?

Axel

 

[Tom B]

The crown is at the exit end of the barrel and protects the rifling from any dents or damage so that the exiting bullet leaves the barrel true. Recrowning is just redoing the crown with a more "true cut" than comes from the factory and this is supposed to increase accuracy.

 

[Axel Yup]

Tom B,

Thanks for the info. When the crown is "recut 45 degrees," what does this angle refer to?

Axel

 

[Michael Carlin]

The centerline of the bore 45 degrees would be half way between parallel and a right angle. 45 is an odd angle for a crown, usually the figure I see for competition rifles in 11 degrees, which I presume to actually be 79 degrees. Confusing, isn't it.

To me you cut the barrel off at 90 degrees, so the correct figure should be 11 degress short of that, or 79 degrees. A 45 degree crown is very radical IMHO.

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michael

 

[Daniel Watters]

Michael, the 45 degree crown is actually quite common for field/service grade firearms. It helps insure that the end of the bore is protected from nicks and dings of daily service. True, it is not the best choice for a benchrest rifle, but a J-frame S&W doesn't require that level of accuracy either.

 

[Walt Welch]

Axel; be sure and have the smith recut the forcing cone; this is often very rough in J frames in particular, and your revolver will benefit from a more gradual angle on the forcing cone, as well as smoothing it.

Be very careful that the smith doesn't lighten up the rebound slide spring and main spring too much; you will get a better trigger pull, but the one I had became unreliable and would misfire on occasion.

Hope this helps, Walt