What to size for Rossi 454 Casull?

[357shooter]

Hi guys,

A new Rossi 454 is on the way, so I've gotta get the other items in order, such as sizers, moulds etc... I've assumed sizing to .454 (over groove size) is best, but I looked at the SAAMI chamber specs. It looks like .454 might not chamber.

Does .454 chamber in your Rossi? Or is .452 the way to go?

Thanks

[missionary5155]

Greetings
What will chamber in my Rossi may not chamber in yours.
When your new treasure arrives slug the throat area or make a chamber cast. Measure your brass thickness at the mouth and you have a good idea what you can do.
Have worked with a couple levers that required brass neckturning to get a fat enough boolit to chamber without stressing the lever.
Mike in Peru

[357shooter]

Thanks Mike, I will make a casting of the chamber. I want to order a custom mould, which takes 6-8 weeks to get turned around. Getting it ordered sooner rather than later is my goal. I typically order them with a "min-size", which means it'll come between the minimum and, up to plus .002. So having a reference point from another Rossi would be helpful. If a couple of guys have them and they take a max of .452, that's what I will order. If a few shoot will chamber and shoot well with a .454 I'll order that size. Otherwise I'll have to wait it out.

[missionary5155]

Howdy
Well then I would go with a .454. It sure is alot easier to size down to .453 or .452 thatn to bump up to .454. But in the long run I would patiently wait till the chamber was in my hands unless you know it will be 6 months...
Mike in Peru

[357shooter]

Thanks. Maybe I need to be more patient!

[RobS]

My LSI Rossi 454 has a .452 barrel on it so I shoot .454 and my wife's Braztec Rossi 45 colt is either .452 or .4525 which also enjoys a .454" boolit. My 454's chamber is much tighter than the wife's 45 Colt with her's being almost sloppy in my opinion. I tore both down when I received them and adjust the ejector springs, made new magazine followers as well as cleaned up all the internals with a fine file and stone. The ones I own are both shooters and I'm sure you'll enjoy yours.

As to boolit design. The RCBS 45-270-SAA feeds in both as does the 454424 or similar variants. The RCBS 45-325-FN U also works if you are after a commercial mold that is a heavy but you'll have to size it down. You will probably not be able to load a LFN style design (.320-.340" meplat) unless the nose length is .380" or less; .380 if the nose profile is a secant and probably around .370" with a tangent nose profile. The Lee 452-300-RF or similar to a WFN shoots fine on the shorter COAL which is something like having a .320" nose length IIRC.

[357shooter]

My LSI Rossi 454 has a .452 barrel on it so I shoot .454 and my wife's Braztec Rossi 45 colt is either .452 or .4525 which also enjoys a .454" boolit. My 454's chamber is much tighter than the wife's 45 Colt with her's being almost sloppy in my opinion. I tore both down when I received them and adjust the ejector springs, made new magazine followers as well as cleaned up all the internals with a fine file and stone. The ones I own are both shooters and I'm sure you'll enjoy yours.

As to boolit design. The RCBS 45-270-SAA feeds in both as does the 454424 or similar variants. The RCBS 45-325-FN U also works if you are after a commercial mold that is a heavy but you'll have to size it down. You will probably not be able to load a LFN style design (.320-.340" meplat) unless the nose length is .380" or less; .380 if the nose profile is a secant and probably around .370" with a tangent nose profile. The Lee 452-300-RF or similar to a WFN shoots fine on the shorter COAL which is something like having a .320" nose length IIRC.

I replaced the ejector springs and followers in my other Rossi's, with a little cleanup the action is very smooth. So the 454 will feed SWC designs?

That's kinda nice. My 357 has a problem with 358-429's, so I might give the 454424 a try.

I ordered the Lee 255-RF so I'd have something to cast right away. I was working on a design on the Mountain Mold site, which I've had excellent results with. I was thinking of a .400 nose and .320 meplat and secant ogive. Sounds like that may not work, or would be marginal at best. A shorter nose .380 nose is in the ballpark I was thinking, so I might go that route.

Thanks for the info.

[RobS]

The 454 of mine had no problems with the two 45 caliber Keith SWC I worked with. You will likely not be able to run a .400" LFN style design because the nose will hit the top of the chamber before the head of the brass makes it past the cartridge guides. I know that a LFN with a secant nose profile design works well at .380 as I designed one for a double up use in lever action and Ruger SRH. I also know that with my 454 a tangent profile design of the same nose length and meplat didn't want to chamber however it will in my wife's 45 Colt Rossi which is manufactured by Braztech. I did end up modifying the cartridge guides on my 454 lever so it would feed my .380" nose length, tangent profile designs which have a .340 meplat.

[357shooter]

RobS, More good info, thanks again. Who are you using for the custom molds? I've been working with some tangent ogive and secant ogives in my 357. Lee put a hold on customer work, and is expensive. I really like the Mountain Molds site and their molds are a joy to cast with. If you have another source I might give them a try too.

I've been using the Cast Bullet Design software from TMT for awhile too. Based on your feedback, I took a 454424 design, turned it into a secant ogive, and added .015 to the nose, the Mountain Mold software measures the nose differently (into the crimp groove) and I've found that I need to add that much to get what I want. I figured that would work, because the main dimensions match the 424 mould. It came out to be a 270 grain bullet. After messing with the length, a 255 with the same nose looks like a good plain base design for low to midrange 2400 loads.

I'd still like to try a longer nose, because the affect on pressure and velocity using H110 is pretty interesting. At least according to Quickload, which has proven to be very accurate and very reliable.

[RobS]

I use AccurateMolds for just about everything custom these days and have quite a few designs over there.