Safe loads for the Cowboy 45 Special

[TheTexasRAT]

WARNING: While some will say it is safe to use 45 Auto load data in Cowboy 45 Special cases, know that the maximum pressure in the 45 Auto is far greater than that of the 45 Colt pistols. So it is not good to use maximum 45 Auto data with cartridges to be use in 45 Colt guns.
45 ACP max pressure 21,000 psi
45 Colt max pressure 14,000 psi/14,000 CUP

CAUTION: If one proceeds in this endeavor they should get the most helpful "Midway USA LoadMAP 45 ACP" in order to be able to choose a safe minimum powder charge to consider (being the Midway USA LoadMAP manuals give pressure ratings for each charge weight). There are some starting charges that are well over the 14000 PSI of the 45 Colt. See the Alliant Bullseye load data on page 70, in the USA LoadMAP 45 ACP, to see just what could happen if one simply willy nillying picks out any old 45 Auto load data and tries it out in the Cowboy 45 Special cartridges in an original or replica 45 Colt revolver, as this starting load is way over safe working pressures of the 45 Colt. Also one should never go anywhere near the medium charge weight load data, as many of the medium charge weights for the 45 Auto are above the 14,000 psi of the 45 Colt gun's working pressure as well. And keep in mind that any load near the 14,000 psi range would defeat the whole reason behind the Cowboy 45 Special case for shooting light Cowboy loads to start with!

And while the 45 Auto Rim and Cowboy 45 Special cases are just a few thousandths of an inch different in length and diameter the 45 Auto Rim's maximum rating of 15,000 CUP [lower than the that of the 45 Auto] is still higher than that of the 45 Colt, so while the starting loads for the 45 Auto Rim can be used safely in the Cowboy 45 Special cases, the maximum 45 Auto Rim loads will still generate unsafe pressures. Always start low and work up with caution. And keep in mind you should be shooting for a light load in Cowboy competition to start with.

But why play around with fire? When one can find proven safe and effective load data for the Cowboy 45 Special cartridge.
Yes, actual Cowboy 45 Special load data can be found in the 17th edition of "Cartridges Of The World", page 486.

And upon these notes I hope y'all have a blast! The Good kind that is.

 

[needsmostuff]

Sooooo much more involved with the equation than the simple pressure limits listed.
Modern 45 colt guns step way beyond limits established for 100 year old guns.
Modern guns, modern steel.
Who made the gun?
Ruger or Italians?
How tight the chamber, how tight the throat?
Read some John Linebaugh writings cuz he backed it up with real life shootin.

 

[pisgah]

While I am in complete agreement that messing around with unpublished loads is unwise, I'll also note that many of the revolvers in which a ".45 Special" load might be fired are also chambered and sold in .45 ACP. In those cases, I would have no qualms at all about using .45 AR or .45 ACP loads in Special brass.

 

[TheTexasRAT]

Sooooo much more involved with the equation than the simple pressure limits listed.
Modern 45 colt guns step way beyond limits established for 100 year old guns.
Modern guns, modern steel.
Who made the gun?

Yes with a Ruger Redhawk on could most likely have no issues whatsoever 45 Auto +P-ing them. Yet that is not what Cowboy Action shooters use either. I do believe that they are stuck with single actions, that at least replicate somewhat an older single action revolver. So I was trying to stick to the intended audience's guide lines.

I personally have a Ruger Redhawk chambered in 45 Colt and I intend to trim brass down close to that of the Cowboy 45 Special cases and load them till my heart's content. I have faith that I'll stop well before the Redhawk lets go. Or at least so I hope. The amount of kick will be the determining factor as to just where I'll stop. If I was going to make them up for one of them Italian replicas or original 45 Colt models I would definitely be sticking with load data on the lower pressure side. Again the whole reason these cases came into existence was for Cowboy shooters who shoot very light loads in the first place, so hot rodding them, as I mentioned in the original post, would defeat their sole purpose in life.

Anyway I'll be sure and put John Linebaugh's book(s) on the list to get for my handloading library. Do you remember the title of the book(s)?

 

[TheTexasRAT]

While I am in complete agreement that messing around with unpublished loads is unwise, I'll also note that many of the revolvers in which a ".45 Special" load might be fired are also chambered and sold in .45 ACP. In those cases, I would have no qualms at all about using .45 AR or .45 ACP loads in Special brass.

Yet surely not in the Italian replicas or the original 45 Colt revolvers, right?

As I previously mention in an earlier post I have a Ruger Redhawk and plan on dumping a full 45 Auto charge of powder in and seeing what kind of kick it produces, then adjust accordingly to my personal preference. I'm not all that worried about working up with this particular revolver. But as with an original or Italian replica I would want to start at the bottom of 45 Auto data and stop low. But there is a load in the Midway USA LoadMAP that starting load is @15,600 PSI, so it is best to either have this manual or use the data listed in "Cartridges Of The World, 17th edition".

And it is because of post such as yours's and needsmorestuff's that I posted this thread to warn and caution them Cowboy action shooters against. Hope you can see my reasoning. If not I at least hope they will.

 

[needsmostuff]

Anyway I'll be sure and put John Linebaugh's book(s) on the list to get for my handloading library. Do you remember the title of the book(s)?

John Linebaugh was the guiding light behind bringing 45 Colt out of the shadows of antiquity and into modern handgunning. He managed to frighten most of the gun writers at the time until they saw that he was on the right track.
As luck would have it this was posted on another site so here you go.
Keep in mind when he refers to a Blackhawk this was before there was a "mid -frame Blackhawk which do not accept the same pressures well.

Dissolving the Myth

THE .45 COLT D ISSOLVING T HE M YTH, D ISCOVERING T HE P OTENTIAL by John Linebaugh When Colt's Patented Firearms Manufacturing Company came out with the .45 Colt in the Single Action Army or...

www.sixgunner.org

 

[NikA]

If you insist on limiting the pressure to 14ksi, .455 Webley data would be your reference point. Nearly identical case volume to .45 ACP with maximum pressure consistent with black powder cartridges.

 

[NikA]

Side note: .45 CS accuracy out of a .45 Colt cylinder is likely to be pretty unimpressive. Bullet will be fully released from the case with ~30 thou freebore prior to hitting the cylinder throats. A number of posts here about the convertible .45 Redhawk performance here support that conclusion.

I always thought .45 CS was more for load discrimination in .45 ACP SA revolver cylinders.

ETA: trimming usable .45 Colt brass to .45 CS length seems a bit silly as well. Dedicated cases are a similar price, and .45 ACP is dirt cheap by comparison.

 

[TheTexasRAT]

If you insist on limiting the pressure to 14ksi, .455 Webley data would be your reference point. Nearly identical case volume to .45 ACP with maximum pressure consistent with black powder cartridges.

I to included them as a side note at one time but then decide to refrain from recommending such due to I was not able to find any pressure data on them. And the 45 Adams which was a softer shooting round has 16,000 PSI and all the other British rounds that followed had higher velocities whereby higher pressures. Anyway being there is legit Cowboy 45 Special load data to be had why confound the issue, after all I'm trying to help people steer away from using iffy data as opposed to tested and proven load data. And I am sure that if one wanted to use black powder they could simply fill the case up to where the bottom of the bullet will set and be good to go without any question.

Side note: .45 CS accuracy out of a .45 Colt cylinder is likely to be pretty unimpressive. Bullet will be fully released from the case with ~30 thou freebore prior to hitting the cylinder throats. A number of posts here about the convertible .45 Redhawk performance here support that conclusion.

I always thought .45 CS was more for load discrimination in .45 ACP SA revolver cylinders.

ETA: trimming usable .45 Colt brass to .45 CS length seems a bit silly as well. Dedicated cases are a similar price, and .45 ACP is dirt cheap by comparison.

Just know I wasn't the one who created it. But it exist. On that note I have seen many recommend that people use any old 45 Auto starting load data for these. I just so happen to find a 45 Auto load data which its starting load is at 15,600 PSI of pressure, so I figured I should add some caveats to that before someone gets hurt.

From what they say on the Starline website, as well as any Cowboy shooting reloaders claim, the cases where made to reduce the useable case volume so reduced loads would not suffer from case over bore issues. That is way to much useable case volume for the small amount of powder. So they were design to make reduce loads safe and effective period. Not to make an accurate cartridge. And as far as I know they fit in the 45 Auto revolver cylinders too but remember they were for Cowboy Action shooting with original 45 Colt revolvers and or their clones, so it is more so a bonus that they fit the 45 Auto revolver chambering than the reasoning behind them.

And yes I know about the bullet jump as well and agree 100% with you on this. Just so you know I am not a SASS or Cowboy Action shooter, as I do not play games with guns. I reserve them for serious business, unless you count plinking. But I see plinking as target practice so to me it is serious stuff.

As far as me personally wanting to trim perfectly good 45 Colt brass down to near Cowboy 45 special cases is because I want the least amount of bullet jump as possible when I load Lehigh Defense's .452" 220 grain Maximum Expansion bullets in them. I feel the Cowboy 45 Special case, as well as with using the moon clips and 45 Auto brass are too short for my tastes. Hence I'll be trimming some perfectly good high dollar Starline 45 Colt brass down to suite my desires. And I would rather it say 45 Colt on the head stamp than Cowboy 45 Special any day of the year. And if I go so far as to do the same thing with the moon clips (keeping bullet jump in mind) I would rather cut down some 308 brass to length than use the shorter 45 Auto stuff. Then again I never was a cheap-skate. Some have actually referred to me as "the last of the big spenders". Personally I would rather be broke than cheap!

 

[NikA]

As far as me personally wanting to trim perfectly good 45 Colt brass down to near Cowboy 45 special cases is because I want the least amount of bullet jump as possible when I load Lehigh Defense's .452" 220 grain Maximum Expansion bullets in them.

This was not clear from your previous post on the subject. Question: why not just seat the bullets deeper in the case to achieve the necessary OAL (using appropriately modified data, of course)?

.460 Rowland data might be a good starting point for this, 40ksi should be fine in a Redhawk.

 

[TheTexasRAT]

This was not clear from your previous post on the subject. Question: why not just seat the bullets deeper in the case to achieve the necessary OAL (using appropriately modified data, of course)?

.460 Rowland data might be a good starting point for this, 40ksi should be fine in a Redhawk.

I guess I did make it clear earlier because I didn't see any relevance in explaining it in great detail at the time. Anyway there are two very important reasons as to why I will not be seating the bullets deeper in the cases. One is because I like to crimp all my rounds and if there is a cannelure groove made for that purpose I feel I should take full advantage of them whenever possible. The stronger the crimp the better chances the pistol powders will have to ignite satisfactorily. So by modifying the case I get to take advantage of the crimp grooves. A much more important thing to do as opposed to worry about trimming down brass. Either way I suspect I'll get the same amount of usage out of each piece of brass. If I had the money I would have Starline make me some special cases, but their minimal order is 5,000 cases - way more than I would ever use. The second reason is the ogive starts immediately after the crimp groove and therefore seating the bullet any deeper would not allow for any kind of a proper crimp. either way I am going to have to develop a special charge for them. This is why I got a Ruger Redhawk so I have the best chances at not blowing the gun up taking guesses as to how much of what powder to use. Of course I will be looking over load data in the "Midway LoadMAP 45 ACP" manual as they list pressures for each load charge weight. I know that I am using a different bullet so the data will not be exact in my specific case usage, but again with a Ruger Redhawk I think I should be able to work things out without doing any harm to myself or the firearm . Hope for the best while preparing for the worst, right?

I know that I normally recommend sticking to publish load data to the T, especially if the firearm is not a Ruger Redhawk, and I know that I am taking a risk that I would never encourage others to do. So again please do not try this at home, as I am what you would call a certified nutcase, and all experiments will be conducted deep in the heart of the Big Thicket of South Texas where nobody else will be around. I have had a Judge for 5 years now but have been hesitant in developing this round for fear that if I over did it on the pressure I might just lose a perfectly good firearm. I finally got a Redhawk and feel perfectly safe to proceed. I am just waiting for the weather to get warmer now is all. I could go into great details as to why I want the temperature to be 100 degrees F when I do the testing, but just know for now after having read through a many a book on reloading to prepare myself for the day and I decide 100 degrees F to be perfect for testing. I could do it at 70 degrees F and rework the formula a little and get the same results most likely. Either way waiting for summer to come along.

Anyway I could go on and on about each detail in my head but I think I'll save it for a book after I pull it off.

 

[XUSNORDIE]

This was not clear from your previous post on the subject. Question: why not just seat the bullets deeper in the case to achieve the necessary OAL (using appropriately modified data, of course)?

.460 Rowland data might be a good starting point for this, 40ksi should be fine in a Redhawk.

NikA you are throwing gas on the fire here......let's put his flames out like others did.....don't want him to burn us here....

I guess I did make it clear earlier because I didn't see any relevance in explaining it in great detail at the time. Anyway there are two very important reasons as to why I will not be seating the bullets deeper in the cases. One is because I like to crimp all my rounds and if there is a cannelure groove made for that purpose I feel I should take full advantage of them whenever possible. The stronger the crimp the better chances the pistol powders will have to ignite satisfactorily. So by modifying the case I get to take advantage of the crimp grooves. A much more important thing to do as opposed to worry about trimming down brass. Either way I suspect I'll get the same amount of usage out of each piece of brass. If I had the money I would have Starline make me some special cases, but their minimal order is 5,000 cases - way more than I would ever use. The second reason is the ogive starts immediately after the crimp groove and therefore seating the bullet any deeper would not allow for any kind of a proper crimp. either way I am going to have to develop a special charge for them. This is why I got a Ruger Redhawk so I have the best chances at not blowing the gun up taking guesses as to how much of what powder to use. Of course I will be looking over load data in the "Midway LoadMAP 45 ACP" manual as they list pressures for each load charge weight. I know that I am using a different bullet

Just take a rest, vanish before being run off as usual, and write the 10 million plagiarised post to validate your whatever and write your book. Those interested in the obvious and unusual will waste money on it. Spare us until then.

Multiple bourbon night......did i spell plagiarised correctly? probablynot don't care. Rack time!

 

[NikA]

@TheTexasRAT, you might look into using a stab crimp created by a modified Lee collet die to crimp bullets below the level of the case mouth. Alternatively, .45 Schofield brass might be the correct length for your project as manufactured. In either case you're going to need to pursue a custom crimping solution because your cases will not be a length for which crimp dies are typically made.

Slight constructive criticism: thread would have been more thought-provoking if you had just started with discussion of the planned custom application. Your OP could really be a single sentence: "published .45 CS data is available in CotW," but since you have neither experience in loading nor apparent intent to load .45 CS, why focus on that rather than what YOU want to do, which is load specific bullets to a custom seating depth/OAL safely?

 

[TheTexasRAT]

Schofield brass is longer as well and would still have to be trimmed some if I am to keep it at 45 Colt OAL. Basically it comes down to which head stamp as nothing came out to the exact length. I know at the time I only had a Judge with a 3" cylinder but I knew I would be getting a regular 45 Colt someday and wanted the end product to be able to fit in it too. Yeh I was always wondering about the crimp once I trimmed the brass, and I know that if I stick with existing case lengths that I could get a crimp die already on the market. I also know that I could lathe down a crimp die. And I could always send in the a case and have a custom crimp die make to suite what ever I come up with. Either way I would want it to fit in regular 45 Colt cylinders with 45 Colt head stamp as a goal.

As to the constructive criticism, the post was not for me and what I am planning on doing. I had though about using Schofield brass as well as the Cowboy 45 Special among others, yet none where exactly the desired lengths so I decided I would simply trim down the 45 Colt brass by Starline (I really like the look of their Head Stamp). But in my studies along the way I found people recommending 45 Auto starting load data for the Cowboy 45 Special. So I looked into using 45 Auto loadings for what I am wanting to do and found some that have starting load data that is higher pressures than what would be considered safe in the SAA 45 Colts and the replicas thereof. Hence the whole reason for this post was to try and help others that are actually wanting to load the Cowboy 45 Special brass by helping them understand not to just take the advise of people on the web about 45 Auto load data without knowing the pressures of the starting loads. That is why I mentioned getting the "Midway LoadMAP 45 ACP" to aid in figuring which specific load data could be used and when to stop on the scale being its show pressure reading at each charge weight. And I also though to try and steer them from trying to find another cartridge of similar case volumes being that the pressures are different and why play with fire when there is actual tested safe load data for the case for which was developed for the intended use thereof. So I titled it to try and draw the attention of the target audience, which is people thinking about getting into reloading with plans on using the Cowboy 45 Special brass for their SASS and Cowboy Shooters alike. My dad, uncle, and aunt being one of them.

Now as for my project, I thought to buy as many reloading manuals as I could find to get the load data for any and all cases with similar useable case volumes to try and get as much data before I played with fire. I also wanted to read the first half of as many of them as I can get my hands on for knowledge of my endeavor. I've gone as far as getting the wildcat books as well to try and glean any knowledge upon the subject of developing a load where there has never been one. After all the experts advise is stick with what has been published, yet there is nothing published for the bullet and case length combination in which I plan to use. And yes I will develop this round at all cost. I am 3 thousand dollars into the books alone and still planning on buying more. I also will be getting more tools and want to build a room dedicated specifically for this hobby. If you think about cost wise I am probably going to make 500 of these rounds at a cost of around $15,000. Talk about not saving money by reloading. But I have some other projects in mind as far as that goes. So I will be able to stay busy throughout my retirement years playing around in my well furnished Handloading room. But at this point I am not really seeking answers from the internet forums on this project as I have pretty much studied it out and have prepared well to this point. Other than the dies of which I figured on having custom ones made to order. There was a pressure trace tool that has been discontinued due to the maker retiring. I missed getting one by one year. So I will just have to do it the old way and measure the case swell and judge by ease of extraction.

And you are right about my experience in handloading as that I am a newbie (5 years in now), but just know this newbie is dedicated to the cause. That being said most of my knowledge and understanding comes from books, YouTube videos, reloading forums, and people I know personally that give me one on one advise. And I was not really seeking advise here just yet, but now that I found this place, while looking into timing issues with my Redhawk, I may from time to time do just that of asking around for specific advise. But then again I have most of the bases covered already on my first three projects. And I just bought a shop manual by Jerry Kuhnhausen on the double action Ruger revolvers to work out the timing issues with the Redhawk, so I will be good there for now (at least until I get it read through). But I thank you for trying to be helpful with this endeavor and if I run into any unforeseen issues I'll be sure and entitle a post here specific to the troubles at hand.

 

[TheTexasRAT]

NikA you are throwing gas on the fire here......let's put his flames out like others did.....don't want him to burn us here....



Just take a rest, vanish before being run off as usual, and write the 10 million plagiarised post to validate your whatever and write your book. Those interested in the obvious and unusual will waste money on it. Spare us until then.

Multiple bourbon night......did i spell plagiarised correctly? probablynot don't care. Rack time!

XUSNORDIE my friend, it is twice now (or thrice but who's counting) that you have not taken you own advise, and are the only one at this moment throwing fuel on a fire. If you want a fire to go out it would seem you would stop fueling it. There is wisdom to be had in the old saying that goes something like this - Doing the same thing over and over again but expecting a different out come is the definition of insanity. Stop the madness, it ain't working the way you think. Just know every time you troll my threads you keep them front and center of the forum. Not to mention displaying your level of wisdom.

As far as writing my book you bet you will find a special place in it cautioning people against taking any of your wacky advise. Yet I'll digress and let you fade into a your drunken stooper.

P.S. - being I do not nee validation from others my flame will always burning bright! There's no putting this flame out! If you do not want to get burned, mind your own business wherefore you won't be meddling mine. One last thought you might try Unwatch-ing my posts and clicking the ignore button so your life can go back to the way it was before you began trolling me.

 

[NikA]

@TheTexasRAT, have you measured your Redhawk to determine what the max OAL is for your setup? I seem to remember that SAAMI .45 Colt OAL is based off the shorter SAA cylinder length. Since you're specifically looking at custom loads in excess of SAAMI pressures, shouldn't really matter whether your cartridges fit into those cylinders.

 

[TheTexasRAT]

Yes I found out that the Redhawk cylinder is 1 3/4". But I am also wanting the round to be able to chamber and shoot safely out of other 45 Colt revolvers. The bullet itself is designed to work around speeds 900 fps and I have seen it tested up to 1,000 fps and under 900 fps. At the higher speed the talons bend overly backwards, and at speeds under 900 they do not fully open. So this dictates that it should be loaded for 900 fps for optimal results. And at these speeds it is absolutely safe for the older SAA and its replicas. And I am also wanting to get a Ruger New Vaquero two which I will also want this round to fit. I will also be using Lehigh defense's .452 220 grain Xtreme Defense bullet but it has less OAL when seated to the crimp groove. But these are two of my special loading that I will need to keep at 14,000 psi if I am going to be able to use them in other revolvers as well. I basically bought the Redhawk as a test crash dumby of sorts being I would be hard pressed to destroy it in my testing. I am a bit timid to try developing the unknown in the other lower pressured revolvers. So I hedged my bet with a Redhawk. I could have gotten a Super Redhawk or even a 460 Magnum, for the extra safety margin but I though that their extra long cylinders would cause too much of a jump causing the tests to be a bit distorted. Turns out the Redhawk's cylinder is a little long but hopefully not enough to overly skew the results. So basically even though the Redhawk can handle excessive pressure, as it is my pressure testing barrel of sorts, I am not looking for higher pressure rounds. The Redhawk was a bit costly but safer than taking a chance of destroying any of the lower pressure revolvers. Once it is developed I can share the load data in my book and any and all will be able to load this cartridge up for self-defense and shoot them out of any 45 Colt revolver safely, not just the Judges and Governors. It is my way of trying to make 45 Colt great again. If I do not achieve the goal I at least get a great self-defense round out of it which was my original intension. So to be able to crimp in the cannelure groove while fitting in normal cylinders and staying within regular standard pressure is my end goal. Anyway as I stated before come this summer I will be blasting away at this goal. After these I have other thoughts as well. Plan three is to lathe me up some .452 caliber 220 grain silver bullets. I love this hobby, its a blast.

 

[vlavalle]

WARNING: While some will say it is safe to use 45 Auto load data in Cowboy 45 Special cases, know that the maximum pressure in the 45 Auto is far greater than that of the 45 Colt pistols. So it is not good to use maximum 45 Auto data with cartridges to be use in 45 Colt guns.
45 ACP max pressure 21,000 psi
45 Colt max pressure 14,000 psi/14,000 CUP

CAUTION: If one proceeds in this endeavor they should get the most helpful "Midway USA LoadMAP 45 ACP" in order to be able to choose a safe minimum powder charge to consider (being the Midway USA LoadMAP manuals give pressure ratings for each charge weight). There are some starting charges that are well over the 14000 PSI of the 45 Colt. See the Alliant Bullseye load data on page 70, in the USA LoadMAP 45 ACP, to see just what could happen if one simply willy nillying picks out any old 45 Auto load data and tries it out in the Cowboy 45 Special cartridges in an original or replica 45 Colt revolver, as this starting load is way over safe working pressures of the 45 Colt.

First, there is no .45 Colt Special. However, there are various forms of .45 Colt ammo. The standard SAMI pressure is 14,000 PSI, but many ammo manufactures have gone well beyond that with the 'newer' .45 Colt capable hand guns from the last 40 years or so. These are called +P, and these vary quite a bit as well. I own a Ruger .45 Colt Flattop Convertible, and with a cylinder swap I can shoot either .45 LC or .45 ACP.

Buffalo Bore makes several .45 Colt cartridges, which are well above the SAMI standard. These .45 +P ammo manufacturers all give warnings about what handgun can actually handle these very hot +P .45 Colt loads. With these very hot loads, the PSI goes well above 36,000. In fact, the max Buffalo Bore .45 Colt cartridge produces 1,344 ft. lbs. of ME Buffalo Bore) or 1,405 (Garrett from 7.5" barrel), which is not too far from the max .44 Mag load of 1,533.


I have actually fired a few of these very hot .45 Colt loads, and they are WAY more powerful than the most .45 ACP round (Atomic at 1,225 FPS, which delivers 616 ft. lbs.). But my Ruger is a flattop, so I have been warned that this is not rugged or strong enough to fire the top 2 o3 loads made by Buffalo Bore. I have shot the round that delivers 1,216 ft. lbs., and I have to use two hands (I normalyl shoot with just one hand, arm extended all the way out), with a glove! Image what the 1,344 ft. lbs. round would be like!

So, this whole discussion about the 'weak' .45 COLT ammo is totally misleading. I have been looking for a .45 Colt DA revolver that will allow me to shoot these max .45 Colt rounds, and it may turn out to be a .45 Redhawk Ruger, or a Casual.

For those who are interested in this caliber, and would like to find more info on it, go to https://www.americanrifleman.org/content/the-misunderstood-45-colt-p/. This gives a very good description on the 'new' .45 Colt +P ammo, and what guns are safe when shooting them. One of the very powerful .45 Colt rounds is made by Garrett, and I have three of these Garrett loads listed in ballistics file under the .45 Colt caliber section. Each if these Garrett rounds is currently (10-12-25) selling 50 rounds for $100 ($2/rd). The third one has an ME of 1,405 ft. lbs. (7.5" barrel).

 

[NikA]

@vlavalle, .45 Cowboy Special is a cartridge case specification, a case with .45 Colt rim dimensions cut to .45 ACP length.

45 Cowboy Special Brass - Large Pistol - Brass Cases

I don't know of anyone that loads it commercially, so you may not have encountered it in your previous research.

 

[TheTexasRAT]

vlavalle said: First, there is no .45 Colt Special. .... ... ... So, this whole discussion about the 'weak' .45 COLT ammo is totally misleading.

While there is no guns chambered in 45 Special there is such a thing as far as cases go. These cases where wildcatted for the sole purpose of being used in CAS and SASS events, so the participants could have a WEAKER LOADING all the while optimally burning the lower powder charges, as it is not safe to use the 45 Colt cases with such extremely reduced charges.

Cowboy 45 Special - https://gunsmagazine.com/ammo/the-cowboy-45-special/