The SEVEN Levels of 45 Colt Maximum Working Pressure

[mike454]

Dec 2, 2021 20:24:22 GMT -5 aciera said:

Yup.....we need not mention Ross’ loads. Lol

I own Ross's Freedom Arms 83 in 45 colt, One of about 60 made, and can tell you that judging from the breech face he was running the old 45 colt pretty hard in that gun!

[chuckhammer]

Dec 9, 2021 18:40:10 GMT -5 savit260 said:

Dec 2, 2021 0:53:21 GMT -5 chuckhammer said:

Based on shooting many of my own .45 Colt handloads over the past 7+ years in various revolvers and leverguns, and also reading everything I could find on the subject from John Taffin, John Linebaugh, Paco Kelly, Brian Pearce, and Randy Garrett, I've assembled the below list of maximum acceptable pressures for each firearm listed.

Looking to get some feedback from others on this topic. Did I leave something out? Do you have experience to the contrary? Fire away.

***Black Powder Only
- First Gen Colt SAA & New Frontier
- BP-only modern clones
- Traditional load is 250-260 gr bullet over 38-40 gr of FFFG.

***14,000 psi (SAAMI max 45 Colt)
- Second & Third Gen Colt SAA & New Frontier
- Modern SAA clones (Uberti, Cimarron, Beretta, etc.)
- Modern S&W Model 3 "top break" clones

***23,000 psi (SAAMI max 45 ACP +P)
- S&W 25 & 625
- Ruger New Vaquero
- Ruger "mid-frame" Flattop Blackhawk
- USFA SAA
- Modern Winchester 1873 clones
- Modern Henry 1860 & 1866 clones

***30,000 psi ("Ruger Only")
- Ruger Blackhawk & Old Vaquero
- Freedom Arms 97
- Dan Wesson
- El Dorado
- Abilene
- Thompson/Center Contender

***40,000 psi
- Marlin 1894
- Winchester 1894AE
- Henry Big Boy

***50,000 psi
- Typical custom five-shot cylinder conversions
- Ruger Redhawk
- Modern Winchester 1892 clones

***65,000 psi (SAAMI max 454 Casull)
- Freedom Arms 83
- Certain custom five-shot cylinder conversions (as specified by maker)
- Thompson/Center Encore

Curious as to why the New Frontier would be listed listed with 1st Gen. Black powder SAA's ?

Just the first generation of each of those Colts, both SAA and NF. The other generation Colts are also grouped together. No distinction that I'm aware of between SAA and NF in terms of pressure level.

[bigbore5]

You forgot the BFR. It's good for 65,000+.

[Encore64]

Also, the Uberti and Pietta Replicas are available in 45 ACP. They're good for the same data as the Ruger New Vaquero...

[chuckhammer]

Yes, good points. I'll update it.

[alamogunr]

Found this thread by accident and printed the first post. A lot of the information is available in different places but this is all in one place.

I have one question: Several years ago I had a SST Ruger Bisley .44 Mag rechambered and re-barreled to .45 Colt by David Clements. I've always considered it to be capable of the same level as an original Ruger Blackhawk.45 Colt. My head tells me there would be no difference and the gun would be capable of the same 30,000 psi as listed in the OP. My head doesn't always come up with the right answer so I'm asking the question. What say the experts?

Someday this gun along with others will go to my sons. I don't want them to be considering this gun capable of handling "Ruger only loads if the rechambering has somehow compromised the strength of the cylinder. I've never pushed it because I've gotten to the point in my life where excess recoil is not pleasant.

[Encore64]

I can assure you rechambering that gun didn't weaken it. It's fully capable of Ruger Only Loads.

[callmaker]

JRH used a 44 Mag cylinder rebored to 45 Colt to fix my Ruger Bisley.
Mine lives it’s life on “Ruger only” data.

[Encore64]

I'm not aware of any Published 40k Loading Data for the 45 Colt. I wish that there was some good pressure tested data in this range.

I'd almost argue that the TC Contender could easily hold this pressure.

Most 45 Colt Brass measures only .002-.003" larger than 300 Savage, 250 Savage, 444 Marlin, etc that I've shot in my TCs for 30+ years.

Those are bottleneck cartridges that hold high pressure longer and increase backthrust much more than a short, straightwall cartridge. They operate at much higher pressure.

[patrick1948]

45 Colt SAA 2nd and 3rd gen can be had with 45 acp cylinders .I question that 14,000 number. From my 50 yrs of shooting and reloading.

[blackmamba]

Here is a great article which lists some 40K loads for 5-shot custom 45 Colts.

www.singleactions.com/FiveShot45Colts.html

[Encore64]

I've always questioned what we know as fact and what we think we know.

Often, I read about cylinder strength based on thickness alone. There are so many other factors.

Which steel is used, proper hardening, etc are also huge factors.

It's no coincidence that Ruger uses Carpenter 465 in their 454 and 480 Guns.

A stainless cylinder made from 17-4 is much stronger than 410, etc.

It's just too complicated for anyone to develop data for individual guns.

Even rechambering Ruger and S&W 45 ACPs to 460 Rowland questions what I've been sure of for 40+ years.

Clearly, I'm not suggesting anyone to go rogue and overload their guns. Just pointing out there are more factors involved than meets the eye.

Yet, we accept the "facts" without question...

[chuckhammer]

Jan 25, 2022 23:36:10 GMT -5 blackmamba said:

Here is a great article which lists some 40K loads for 5-shot custom 45 Colts.

www.singleactions.com/FiveShot45Colts.html

Thanks for sharing. That's a great article but I don't see any 40k load data. He shows standard, Ruger-only 30k data and then his own 50k data he developed for his 5-shot cylinder.

We do need some 40k data, preferably with a variety of suitable powders and bullets. If only I had pressure testing equipment...

[Encore64]

I didn't see any 40k Data either. I do the same as Lee and maintain safe data. But, don't have pressure testing equipment to confirm.

Can't complain about 45 Colt Data. It's been widely exploited and we have lots of loads available.

Guess it's human nature to want more. It's just such a versatile cartridge.

[blackmamba]

Sorry if I mislead, I didn't reread the entire article before I posted it. Still lots of good info there. At the ragged end of Ruger Only loads, one or at most 2 grains more of any of the slow powders like 2400, Accurate #9 and 4100, 296/H110, etc., are gonna push you to 40 kpsi.