Recently while in my LGS discussing S&W revolvers when the owner asked if anyone had any idea why S&W decided on 8 3/8" barrels. Why not something more standard like 8" or 8 1/2"? He had us all scratching our heads. Would any of you have the answer?

I dont remember the organization (NRA?) but there is/was a pistol competition that restricted the sight radius (distance between sights) and the 8 3/8" was built to conform to those rules.

Incidentally, the 8 3/8" barrel is the only barrel found on a Registered Magnum that is not a 1/4" increment

29aholic has the basic answer.


But as an aside:

When it comes to barrel lengths in S&W revolvers, I've found they vary. Many were advertised as 4 inches or 6 inches for instance but a careful measurement will find they are often an eighth of an inch or quarter inch in variance.

I just bought a 6 inch Model 27 produced in 1975.
But I measured it and it's really a 5 3/4 inch barrel.

Over the years I've found many variances among Model 14 and 15 revolvers.

Today, maybe with the new standard for so called 4 inch revolvers to be 4.2 the lengths are truer.

"United States Revolver Association" (USRA) rules prohibited revolvers with a longer sight radius than 10" for competition. The longest barrel that stayed within the rules was 8 3/8". I always wondered why S&W did not just set the front sight back 1/2" to comply with the rule instead of shortening the barrel!

__________________
Gunsmithing since 1961

Yeah I had two 4" 29-2's one was 3 7/8" and one was 3 3/4" I called Roy on it and he told me it was just a finishing variance

IN the land of commerce, enterprise, and good ole American economics, it may well have been how many combos of barrel lengths could be harvested from an exact 20-ft. piece of round, cold-rolled stock, tool steel.

__________________
wanna do right-- not right now

I have always suspected this, a "finishing variance."

I've had a mental image of a Smith worker screwing in a 6-inch barrel, not quite getting it right, and redoing the threading so that now it's a 5.5 inch barrel.

Again not quite right and by the time he's done, it's a 3 3/4 inch barrel.

I'm sure it doesn't work that way but I've always had fun imagining it.

Nope. At worst a barrel would have to be taken around another turn (1/36 of an inch shorter) in this scenario. If you start taking .500" off the back end of the barrel, problems with the length of the ejector rod need to be dealt with.

Bruce

Interesting question, gives us guys who like the long tubes something to lust after...