45 Colt & Unique

[bishopgrandpa]

THE GUN THAT WAS MADE FIRST BY RUGER FOR THE .44 MAGNUM ROUND. Lately Ruger has produced some special run of guns in .44 Magnum chambering that again have the fluted cylinder feature. Also a few early Bisleys were fitted with FLUTED cylinders in .44 caliber. However most were unfluted roll marked cylinders. But the most important factor we have found here is there is very little difference in strength between a fluted and non-fluted cylinder. The strength of the cylinder can vary more from the quality of the material and the tensile strength of the part due to different points of hardness. When steel is heat treated it can easily vary a couple of points. This is only a few thousand pounds of tensile strength but this is likely to mean more to absolute strength than the difference in the design of the part in the argument between "fluted" or NON-Fluted". The important fact is that the initial part (in this case the cylinder) was OVER ENGINEERED to account for these variables. They are amply strong to safely handle any safe load. To DEFINE SAFE: ANY LOAD THAT DOES NOT EXCEED THE INDUSTRY'S RECOMMENDED MAXIMUM OPERATIONAL PRESSURE.. In the case of the .44 magnum, this is 40,000 CUP. Not to exceed 43,500 ABSOLUTE MAXIMUM.

The Ruger Blackhawks and Bisley models chambered for .45 Colt are approximately 80% as strong as the same Ruger chambered for .44 magnum. This means we can load the .45 Colt to 80% of the pressure of the .44 Magnum round and still maintain the 100% safety level. 80% of 40,000 is 32,000.

To check our findings we again turned to H.P White Labs and their findings paralleled ours. Ruger Blackhawks in .45 Colt caliber were destroyed in controlled test conditions at approximately 60,000 CUP pressure levels.
From an article by Linebaugh

[Walks]

.45 Colt Loads

Went back to the Lyman #38 Handbook. They had some rather HOT LOADS with Unique back then.

Shows the #454424 with a real hefty charge of Unique, the #454190 too.
No loads shown with the #452423 - 240gr, but the #454309BNWC - 237gr, is shown. And yes the #452423 is .452dia, it was designed for the .45 Auto Rim.

A bit warmer then I'd shoot in My NM Blackhawk, but not by much.
Don't shoot those warm Ruger loads anymore. That's what a .44MAGNUM is for.

I have one of those "new" Vaquero's in .45Colt, treat it just like I do My Colts & Spaghetti clones. Std Pressure loads.

[DougGuy]

I have one of those "new" Vaquero's in .45Colt, treat it just like I do My Colts & Spaghetti clones. Std Pressure loads.

I too have one of the three digit prefix New Vaquero models. Ruger chambered these in 45 ACP, and they are safely rated to 45 ACP+P 23,000psi, which means the 45 Colt cylinder is also safe to this level due to the same thickness cylinder walls in each caliber.

Before Osammy signed off on the EO making conversions manufacturing, I fitted a 45 ACP cylinder to mine, then reamed it to 45 Schofield. I figure Ruger gave us a danged fine tier 2 platform, lets reduce the case capacity, therefore increasing load density, and have some fun with some mid level 45 loads. I got a 250gr LBT OWC to 1200fps using 21.5gr H110, and still stayed (according to QuickLoad) under the 23,000psi ceiling the gun is rated for. I found it snappy but not sharp, not nearly as punishing as Ruger Only loads in the full size BH or Original Vaquero. It will be my woods walker in deer season.

I don't think I would meet this level of performance with Unique before I ran out of headroom, but I am sure I could get 950-1000fps in Starline's Schofield brass with a sensible load of Unique.

[USSR]

I too have one of the three digit prefix New Vaquero models. Ruger chambered these in 45 ACP, and they are safely rated to 45 ACP+P 23,000psi, which means the 45 Colt cylinder is also safe to this level due to the same thickness cylinder walls in each caliber.

Yep, same holds true with the S&W Model 25's - rated for 23,000psi, so Tier 2 load levels are fine.

Don