Deacon,
The reason I ask about the statement
"Their barrels have rifling set up for FMJ bullets. Unless you use a very hard cast bullet, it will not play well with non-jacketed bullets" is because there is a lot of “common knowledge” floating around the internet and it even pervades the S&W collectors community. Once it is said it gets repeated without evidence or even measurement.
The M1917 started out as an “Americanized” version of the S&W the British bought chambered in the .455 Mark II Webley cartridge, it was basically a S&W Hand Ejector (First Model). Now go look up the dimensions for a .455 Webley, they are larger than the .45 ACP. Some of the early M1917 revolvers in .45 ACP even used that original .455 Webley barrel, you have to know the vintage of a M1917 to even guess what the rifling dimensions might be.
BUT, then they started producing barrels specifically for the .45 ACP and it will surprise you to know what the land and groove dimensions were. The ones I have measured have the Lands at Ø.443 or Ø.444 and the Grove diameters were Ø.454 or Ø.455. They can argue all they want, I have actual measurable barrels and the tools to measure them.
SOOOOO… What does shallow groove mean? Shallow as compared to what? The Nominal dimension for the Lands on a National Match 1911 .45 ACP barrel are Ø.4410 +.0015/-.0000 for the lands and Ø.4505 +.0015/-.0000 for the groove. That means the nominal groove depth is .00475”. Sounds pretty shallow when you look at it that way. You can take a DEAD SOFT H&G 68 200gr SWC and almost stack the holes (a bit of an exaggeration) at 25 yards using a Ransom Rest. The Jacketed 230 Match and 185 Jacketed Match ammo really don’t do any better.
Look at this illustration: This is what Kimber was using 29 years ago when Jerico first started making the 1911s.
Does anyone say the 1911 barrel with a .00475” groove cannot shoot anything except Jacketed or HARD lead bullets?
I have rebarreled a S&W 1917 and have the M1917 barrel around somewhere in my mountain of boxes from storage. I have owned a couple as well, I mainly shot either lead 230gr bullets or H&G 68 SWCs through them. Based on the one I put a shortened 1950 barrel on and my experience with shooting a lot of S&W .45 ACP revolvers I can tell you the barrel rifling is pretty much the same as you find on a S&W 1950, a S&W 1955 and the current Model 25s which are just the new numbering for the 1955 (the 1950 became the Model 26). The major differences are the barrel profile and rib changed from the M1950 and remains the same today on the Mod 25. The other difference is that the newer M25 and M625 no longer have the pin through the threads on the top of the barrel extension locking it to the frame.
Look at these pictures:
Both barrels are M1950, I no longer have any loose 1955 barrels. Both of those barrels have a Land diameter that will pass a Ø.443+ gauge pin and the groove diameter is Ø.453- That is a groove depth of .0050” (sounds awfully close to .00475”, but then again, what is 250 millionths among friends?) Those cylinders will pass a Ø.454+ gauge pin.
A tuned M1950 or M1955 will also shoot incredibly tight groups with almost anything you stuff in them. They even shoot well (but not as good as .45ACP) when .45 Colt cylinders are added to them. That is with the same bullets too. The advantage of the .45 Colt is that you can shoot those 250gr bullets and even heavier if you have a mind to. I even have box of .45ACP loaded with 250gr bullets around here somewhere. They don't feed reliably in a 1911 but shoot "okay" in a revolver, they were loaded decades ago and I ran across them during a move.
Deacon, this is no reflection on you, you're just repeating what the "experts" say it is... It's too bad they are not diligent students or good at collecting data. I’m sorry, but I get a bit tired of reading things I know there is no basis for. I know I don’t know everything (not even a trillionth of a fraction of everything) but there are some things I do know. I also know there is a LOT of bad advice, conventional wisdom and “that’s the way it was done back then” for Black Powder. Most of it is WRONG.
I think I will start a topic of "Things we all know, but are wrong about Real Powder". But not now, I would get pissy about it.
I'm sorry, but I've been cooped up in a convention center, got home late yesterday and just finished "doctoring" 2 one week old chicks who had "Pasty Butt", replaced 3 Guinea Keets that didn't make it from last week and it seems to have made me grumpy.
I almost swallowed my tongue at the Farm Store early this morning when I was getting replacements (they guarantee them within reason), and the guy at the register asked if I wanted to "exchange" the Keets for new ones. The woman next to him just rolled her eyes. I told him, "I don't think you would have wanted me to bring those in and slap them on your counter..." Well I do get some simple pleasure from people's obtuse reasoning...
~Mako