Is this electrochemical machining (ECM) rifling?

[Carmady]

Is this electrochemical machining (ECM) rifling? It's on a 1996-2001 S&W J frame.

 

[Dufus]

S&W started using that type of rifling process in 1993, so I would say chances are better than good that your revolver was rifled using that process.

 

[ThomasT]

That looks like cut rifling to be because the ECM rifling looks like it has more rounded lands. I have a 442 and a 637. The 637 for sure has the ECM in its two peice barrel but the one piece barrel on the 442 appears to be cut rifling. But I ain't swearing to nuthin'.

 

[Carmady]

I'm not sure what I should be looking for, but I looks to me like the lower inside corners (where the grooves meet the walls going up to the lands) are rounded, not a sharp angle. Maybe I'm seeing it wrong, but the diameter is about 2 1/4" on the computer screen.

 

[ThomasT]

Your most accurate answer may come from the guys over at the Smith-Wesson forum. But I bet the poster Dufus is correct. But if they look rounded they are probablt not cut rifling but the ECM/EDM rifling.

 

[BurningAmmo]

If that rifling was on a Colt, all holy hell would break loose.

 

[Carmady]

^^^LOL That was good.

 

[4V50 Gary]

I can't tell from a picture of the muzzle but I will say that machining on the muzzle is pretty sloppy.