Does anybody know what the throats would be on a .45 ACP cylinder?

The reason I ask is because my 3rd Gen Colt's regular .45 Colt cylinder has .455 - .456" diameter throats.  If the .45 ACP has .451 - .452" throats I bet the Cowboy Special could be a tack driver.

Are you asking about Colt cylinders? 

…however double action revolvers, the 1917 colt /smith and the Model 25 /625 smiths. They are cut for 45acp in moon clips or 45Autorim but will not fire loose 45acp/45cs as there is too much space between the case and firing pin. …

Sorry, my experience with ACP revolvers finds this to be incorrect, at least with S&W. Yes, the double action revolvers are indeed, cut for the use of moonclips.  But, the ACP cartridge will still headspace on the case mouth and fire.  It will not extract or eject because there is no rim.  That is why the moon clip was developed and patented by S&W.  For S&W, building a revolver to fire the 45 ACP, was easy.  Getting the cartridges out of the cylinder, in an efficient manner, was the hard part. 

At the request of the Army, S&W permitted their competitor, Colt, access to the moon clip so they could also design a revolver to fire the 45 ACP cartridge.  Colt promptly stuck their foot in it by cutting the chambers straight through, no throat.  This prevented the revolver from using loose ammunition.  Once the Army discovered this, they made Colts correct the problem and fix any revolvers returned to them. Considering they were also building the Model 1911, they should have know how to cut a chamber.

Just one note on actual S&W 1917 revolvers. 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.

Yes, indeed, the rifling is cut just as the Army specified it be cut, for Hardball.  However, target competitors soon figured out how to make the ACP revolver competitive…with lead bullets.  Hard lead bullets are really not an answer to this problem. The proper size bullets are what matters. My personal load development has shown that a .454 diameter cast bullet, with a long bearing surface, produces great accuracy in a lot of revolvers. And very good accuracy in the rest. Here is the bullet, on the left.

I have more than a few ACP revolvers. I do not try to find a specific load for each one. Instead, I have found one load that gives acceptable acceptable accuracy in all of them. The SAECO 453 over a hardball dose of powder. 

…

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…

~Mako

Who told you that?

The S&W Hand Ejector First Model, aka New Century, aka Triple lock, was introduced to the Army in the 45 S&W Special cartridge. Once the Army chose the Model 1911 in 45 ACP, S&W introduced the New Century to the public chambered for the 44 S&W Special.  The British Army was a bit short of sidearms to fight WWI so they contracted with S&W to buy revolvers chambered for the 455 cartridge. Even before the first shipment of the Triplelock was delivered, the British Army complained it was too heavy and the complicated mechanism would jam in the mud of the trenches.  S&W redesigned the revolver and produced the Second Model Hand Ejector, less the third locking mechanism, less the shrouded ejector rod.  It was this revolver that was used to create the Model 1917 (or Government Model as it was called in the factory).  Joseph Wesson realized the US would be dragged into WWI and in 1915 tasked a group of engineers to build a revolver that would fire AND eject the 45 ACP cartridge.

The 45 ACP Second Model Hand Ejector, aka Model 1917, was the result.

… 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.

~Mako

The barrel dimensions were specified by the Army.  Did the barrels you measure have the Army acceptance stamps on them?  Unfortunately, many of the 455 First Model Hand Ejectors, aka New Century, aka Triplelocks, were rechambered for the 45 ACP cartridge. These were not ever accepted by the Army.

The Model 1917 was also the first S&W revolver to have a heat treated cylinder.  It was a requirement of the Army.

… 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.
…

~Mako

At some point, when the Model 625 was introduced, the rifling was changed.  It reverted to the common S&W 5groove rifling.  I am not sure if the rifling pitch is different from what the Army required. Also in the 625 series, S&W engineers decided to go the route of Colt and cut deep charge holes that REQUIRED the use of moon clips. But, that was sporadic enough as to be poor quality control.

Kevin

With so many worried about our dependence on tech-luxury, here's a few hacks from our frontier past...
Survival Hacks When Less is More: Alternate Uses for Common Old West Items

How Did Old West Travelers Treat Life's Little Emergencies Without Towns or Stores Nearby? Here are Some Ideas on Making Do With What Little You May Have in Your Bullet Pouch, Bedroll, and Saddle Bags

Anyone reading this will know a few hacks of their own. Either a grandparent's sage advice or friendly conversation with a venerable elder, reminiscing about "back in my day..." has left you with some gem of advice that you have used to impress friends with. Here's a few more for the collection...


When traveling the 19th century American Frontier, a variety of problems can come up and in many cases, the only thing available is in the bullet pouch, pockets or saddle bags. These little 'hacks' are more than just interesting topics, they were essential nuggets of knowledge that many of our frontier ancestors used. I used some content from my previous article on frontier medicine since it was appropriate to explain the medical properties of some everyday items. The rest is from my new book coming soon.

For more reading, follow the link:
https://www.frontieramericanillustratednews.com/post/survival-hacks-when-less-is-more-alternate-uses-for-common-old-west-items-1

Mako, MP Molds makes the 454-423 Plain Base Solid which looks very similar the the Lyman 452423 .45 cal 242 grain bullet.

https://www.mp-molds.com/product/mp-454-423-pb-solid/

I do have this mold from them. Although it says .454" mine always seem to drop closer to .452" with plain lead or 1:20. I haven't used it much, I usually use the Lyman/Ideal 454190.

Going for groceries, Rita is making shrimp mac and cheese tonight, I'm making Sloppy Joes tomorrow and some homemade bread, going to make plenty and freeze.  Going to make extra iced tea and put it in quart jars undiluted.  Give us stuff for the rest of the week without having to do much.  A friend of Rita's is taking her and my youngest taking me, different hospitals.  Then Rita's daughter is going to pretend she is a responsible adult and going to stay here Tuesday night.  We are both supposed to do it outpatient but things can change.

I'll be praying.

Slim

Tornado
Thanks, I have one on the way. Looking forward to RXing it.
Macon