cimerron 73 win clone

[Catch]

I'm shooting the above rifle in 45 colt cal. and even with different powders (mostly slower) am finding the cases with heavy black streaks on one side. Is this normal? Do I need a faster powder or maybe a harder crimp to start with..
or a larger bullet. The groove dia. is .452 the best I can tell. It likes the .454 cast wheel weights best. Should I change something or just clean the empties..........Thanks folks ........catch

[freakonaleash]

My cimmaron rifle in .45 does the same thing. Both black powder and smokeless. It really doesn't hurt anything, but I wish I would have bought a 44 40 instead.

[Randy Bohannon]

Try annealing your brass should stop the blow by.

[Larry Gibson]

I also have a Uberti '73 in 45 Colt. It will do the same thing if I size the cases in a carbide die. That die puts straight sidewalls on the cases. The Ubertis have standard SAMMI chambers which have a taper to them. Bottom line is you're resizing the cases too much. Three solutions; first is back the sizer out so you only size the fired case to the seating depth of the bullet used. You end up with with a slightly bottle neck cartridge similar to a 44-40. Problem here is with heavier loads, or ammo also shot in a revolver, chambering may become a problem. Second is to get the Redding dual diameter sizer for the 45 Colt. Problem there is it can be spendy. Third is to find an older steel FL sizer which sizes cases to the chamber taper. Problem there is you are back to lubing the cases before sizing and then delubing the cases after sizing.

I've opted for the third solution. I clean the cases. Then lube with a spray lube and size them in an RCBS steel FL sizer. I then clean the lube off by tumbling them in sawdust for 30 minutes +/-. The cases are then loaded on a Dillon SDB with the sizer removed from station 1. Goes pretty quick and the cartridges can be used in my '73 and both Uberti SAs.

[Baltimoreed]

Most lever guns in 45colt soot up the brass. My marlins and ubertis do it. You’ve got to load them hot to expand the brass and seal the chamber. But they clean right up in my tumbler. If it really bothers you you can use 44-40 brass and load it like your 45colt. 44-40 is much thinner and will seal the chambers but is trickier to load. It’s real easy to crush a case. Guys who shoot black powder always use 38-40 and 44-40. Keeps their guns cleaner.

[Frank V]

Sometimes soot on cases mean the case isn’t expanding enough to seal the chamber. With the 73 we do have to watch pressure though, even with modern replicas.

[indian joe]

Try annealing your brass should stop the blow by.

this !!!!!

[veeman]

Trade it in for the proper 44-40.

[BB57]

I posted this on other forums both recently and in the past, but it’s apparently worth repeating here. Neither Winchester nor Marlin ever chambered a lever gun in .45 Colt, at least until long after the black powder era, and for good reason.

The .45 Colt was designed for the Colt SAA / 1873 Army and Colt’s design goal was to pack as much black powder as possible behind the .45 caliber bullet while keeping the cylinder diameter to a minimum. To do so, they strayed from the methods used to minimize chamber fouling, gas coming back into the action and extraction forces associated with black powder fouling.

Normally, the conventions for a black powder round were to:

a) slightly taper the case to reduce extraction forces by ensuring the entire case body came out of contact with the chamber as soon as the case moved aft at all. You see that slight taper in the .32-40, 38-55, .38-70, .40-60, .40-65, .40-70, .40-72, .40-82, .45-60, .45-70, .45-90, .45-110, .50-110, etc.

b) in addition to the tapered body, a slight bottle neck was also often used as the bottle necked portion of the case was readily blown forward and would seal the case against chamber quickly even at low black powder pressures. The bottle neck, even a slight one, would significantly reduce the amount of fouling in the chamber as well as the amount of gas coming back into the action.

You see both approaches used on the smaller pistol class rounds Winchester designed for the 1873, 1892, etc. The .44-40, .38-40, .32-20, and .25-20.

You see both these features as well on other rounds like the .22 WCF, .25-35, .30-30, .32 WS, .33 WCF, .38-56, .38-72, .45-75, and .50-95.

Consequently, when Colt went for maximum volume and minimum size and opted for a parallel wall case with no taper and no bottle neck, it was stepping well off the reservation. Colt could do so because the Colt SAA used a rod ejector, a first in a revolver, and did not rely on an extractor engaging a rim for extraction. This meant Colt could also design the .45 Colt with a very thin and small rim as all it had to accomplish was head spacing.

However, Colt still hedged its bet a bit and used a .007” taper from mouth to base in the .45 Colt chamber. This meant as soon as the parallel wall case in the cylinder moved aft, it once again moved completely out of contact with the tapered chamber wall.

Despite that taper in the chamber, the S&W Schofield revolver used a shorter version of the .45 Colt (the .45 Schofield) as the shorter case, lower pressure and reduced fouling from the smaller powder charge allowed the star ejector in the Schofield revolver to eject all six cases in the cylinder. The .45 Schofield was first a substitute standard and then became the standard cartridge for both the SAA and Schofield revolvers. Which meant for a time there were both .45 “long” Colt and .45 “short” Schofield cartridges in service.

Once the .45 Colt moved into the smokeless age, it ended up with a wider and stronger rim, and eventually it was even chambered in lever action rifles for which it had not been designed, and in which it would not have allowed reliable extraction with black powder loads.

——

In regard to the OP’s smoked case issue, 150 years after the .45 Colt was designed the SAAMI chamber dimensions for the .45 Colt still have that .007” taper. That means the case has to stretch to fill that gap at modern smokeless powder pressures, which when full length resized works the brass in the case body significantly more than cases like the .32 H&R, .38 Special, .44 Special, .357 Mag, .44 Mag, etc.

The gap is still very slight at the case mouth, but as there is no bottle neck, there isn’t any assist for the gas pressure to seal the case against the chamber wall. More gas coming back into the chamber is inevitable. (It’s also not significant enough with any smokeless powder to be an issue, and I frankly would not worry about it at all.)

You’ll get less smoking of the cases at higher pressures with “Ruger only” loads that exceed the standard 14,000 psi SAAMI pressure that do a better job of sealing the case quicker, but those higher pressure loads also increase the expansion of the brass and shorten case life.

You can extend case life a bit in higher pressure loads by partially sizing the case just enough to hold a new bullet and leave the bottom half of the case, where most of the expansion occurs in the tapered chamber, unsized.

You can also anneal the case. However, while that might extend the life of the case mouth and allow the softer brass to seal better at lower pressures, it doesn’t really address the expansion related work hardening at the base, unless you anneal down near the base of the case and take on the substantial risk of a too soft case head then failing under pressure.

The 1873 has a very slick and smooth action, but it’s a comparatively weak toggle link design. Modern reproductions are stronger than the originals due to better metallurgy, but the .45 Colt has a large base diameter and hot loads will just prematurely wear on the design and eventually result in excessive head space. If you want more performance from the .45 Colt, you need to get a Model 1892, which is a much stronger design far better suited to higher pressures.

I recommend just staying with the 14,000 PSI SAAMI limit with the Model 1873. If smoked cases are something that really bother you, then I recommend using a fast burning powder like Bullseye, Red Dot or Tite Group rather than a relatively slower powder like 231, Universal or Unique. You’ll lose a little velocity compared to a slower powder but it will be “cleaner”.

[Baltimoreed]

Very well written description BB57. Thanks for posting.

[Thundermaker]

Now you know why Winchester lever guns were never originally chambered in 45lc.

Annealing and a good crimp might alleviate the issue.

[Frank V]

Trail Boss is an excellent powder in the .45 Colt & you cannot seat a bullet on a double charge. A double charge comes to within about 3/8” from completely filling the case.

[indian joe]

whats been missed here is the difference in thickness of 45colt brass (at the neck end) compared to the winchester dash calibres - its a decent difference - take a look at a 44/40 case mouth and compare ...................

[Thundermaker]

A good case annealing, a good roll crimp, and a heavy bullet will help towards alleviating the problem.

[greenjoytj]

I have a Miroku/Winchester 73 rifle and Ruger New Vaquero revolvers both chambered in 45 Colt.
The load I use the most is 35 grains of 2fg O.E Black Powder and 9.2 grains of CFE-Pistol, a CCI 350 magnum primers in both loads with a Lyman 452664 bullet cast 20:1 alloy.

I was using Starline brass and was getting blow back fouling in the tight chambered revolver and the rifles looser chamber.

I annealed my the Starline brass (I’m sure I actually over annealed it, dull red heat on the case necks) and the blow back fouling was reduced by at least 90%.
I have some thinner cases Hornady and Winchester, I anneal them too and they reduce the blow back fouling even more.

[00buck]

I just shoot them
Clean them up and reload
I just accept that is the way it is.

[Walks]

The smokeless loads that shoot clean in My Marlin Cowboy will shoot dirty in My Uberti 1866.
It's a different story for My 2 Uberti 1873's in .44-40, they shoot Clean with smokeless and a whole lot cleaner then the .45Colt chambered guns with BP.
Using a steel sizer in .45Colt does help. I have an Old Lyman die set from the early 1960's.

[Griff]

The 45 Colt and 45 Schofield are not interchangeable... The Schofield uses a different rim than the Colt. Most Colt SAAs won't chamber the Schofield round. The rim is too thick. There was another "short" round that used the same charge as the Schofield but in a shortened Colt case. The 45 Colt Government. Don't mix up the two. The 45 Colt Government went out of production in the late 1920's or early 1930s.

The correct way to lessen the soot on your 45 Colt rifle is to anneal the cases.