S&W Product “Improvements” in 1990s

[TheTinMan]

Frame mounted firing pins don’t upset me. Transfer bars are OK if they don’t gum up the trigger pull. I have 3 Dan Wessons with barrel sleeves and shrouds so that concept doesn’t bug me. MIM is fine when done well and on most (but not all) parts.

One thing I hadn’t ever heard about is the change to EDM rifling sometime in the 1990s. I’m well past the halfway mark in life but don’t automatically assume it’s bad just because it’s new. However, this sounds like Marlin’s switch to “Microgroove” rifling in the 1950s. That was a cost cutting measure with negative effects for some bullets. Marlin only started going back to normal rifling in the 1990s on special editions. New Marlins (Ruger ownership) all have normal, cold hammer forged rifling.

Most of my revolvers are pre-1960. I own exactly one post-millennium - a 25-10 in .45 Colt which is not built like then-current production Smith & Wessons. So what’s the consensus on EDM cut rifling? More accurate? Less leading? Dog’s breakfast?

 

[Piwo]

In the newer guns from S&W I have noticed less leading and easier cleaning generally than the old cut rifling guns. It may be possible the bores are a little smoother. It may also be possible that the cylinder throats are better matched to the bore diameters too.

 

[Rock185]

Easier to clean, otherwise I haven't noticed any difference..

 

[minconrevo]

For a while, I was involved in the manufacture of ECM pistol barrels. Done properly, with attention paid to tight specs and careful quality control, a superior barrel can be produced. Under .00002" variation per inch of barrel is possible. Extreme barrel interior smoothness is possible.

Like so many things, it's all in the details.

 

[TheTinMan]

For a while, I was involved in the manufacture of ECM pistol barrels. Done properly, with attention paid to tight specs and careful quality control, a superior barrel can be produced. Under .00002" variation per inch of barrel is possible. Extreme barrel interior smoothness is possible.

Like so many things, it's all in the details.

Thanks - I had heard complaints that the S&W ECM barrels didn’t shoot lead well. Sounds like ECM is a lot like MIM - done right it’s less expensive and better than older methods. Without attention to detail and strong QC…

 

[BLUEDOT37]

The EDM/ECM rifling's clearly not as sharply defined, when viewed at the muzzle, as broach cut but it clearly doesn't make a difference in accuracy for me. I have way more EDM/ECM cut barrelled pistols & when they're right they're good shooters.

For me, either one will & can lead the barrel. I just stick with plated or jacketed bullets.

One thing I've noticed is that two-piece barreled revolvers, which are all EDM/ECM cut (from my experiences) have very uniformed shaped & smooth forcing cones. For some reason it appears on these barrels the forcing cone is done with the EDM/ECM process & are generally superior to the forcing cones on the one-piece barrel revolvers which have EDM/ECM cut rifling but then the forcing cones are reamed/chamfered (by hand) often with a less than stellar result.

.

686-6+, 2012, EDM/ECM cut rifling
.


.
.

627-5PC, 2014, broach cut rifling
.


.

 

[stansdds]

Smoothly cut rifling and forcing cones does not surprise me with EDM or ECM cut bores. No cutter to wear or chatter, so smoother finish, much like the MIM parts that some people seem to think are the spawn of Satan.

 

[brucev]

Thank you for posting your question and for the responses. Sincerely. bruce.

 

[TheTinMan]

Thank you for posting your question and for the responses. Sincerely. bruce.

I want to echo Bruce’s thanks for your responses.

EDM rifling is not Satan’s spawn after all!