How hot?

[Blind Hawg]

How “hot” is a .44 mag 240 grain JHP over 22.2 grains of 2400 in a Rossi 92?

[Archer]

It exceeds book max from at least 4 manuals by at least .7 grains.

It might be fine out of the 92 especially in cold weather with cold weather/gun/ammo.

I probably wouldn't run it in hot weather.

My go to load was 20.0 grains of 2400 at 1.6" OAL with a 240 grain bullet and a WLP or FMP primer.
I used that mostly out of a Win 94. It annoyed the neighbors out of the Kodiak with the magnaporting or the 629 with the factory comp.

[Ohio3Wheels]

Not sure what bullet brand you're using so I used the Speer since that bullet file was loaded. Quickload shows the SAAMI max in the 44 Mag at 36000 psi it shows this load at 43113 psi. Based strictly on QL data I'm not sure I use that load but YMMV.

Make smoke,

[Archer]

Safest bet is to pull any rounds loaded to that level and start over.

The argument can be made that the 92 action is built in .454 and .480 Ruger and the .454 pressures run higher than you are probably going to see in the .44 based on the QL data.

ON THE OTHER HAND...
You are potentially significantly exceeding the .44 pressure limits.

There is a safety factor built into the system BUT...
Regarding the brass cases if you have a sloppy chamber, if the chamber is somewhat unsupported because it has a 'feed ramp' cut into it, if the brass you are using has been previously fired that safety factor can be greatly reduced. I have seen factory brass show a pin hole in the side of the casing after a single firing and resizing cycle.

Regarding the rifle, the 454 and the 480 as I understand it have a threaded magazine tube and receiver instead of the slip fit on the other calibers to help prevent inertia from firing pulling the mag tube forward while the rifle recoils. We have seen the mag tube pulled forward in just that manner on at least one member gun reported on this site. Even if the action and the brass handle the pressure you could wind up with the recoil attempting to remove your magazine from the gun.

Another reason to pull the rounds is the fact that you never know when ammo is going to find it's way to another weapon that may not be as robust. I've seen rounds 'borrowed' at the range, seen ammo come into a gunshop for 'disposal', seen guys selling or giving away dead guy stuff that includes reloads without any providence or data. I have personally disassembled a couple hundred .30-06 rounds that I was gifted rather than trust that they were safely loaded. I found at least three bullet weights in the sack of mixed stuff.

[Blind Hawg]

I've since reduced to 20 grains.

[GasGuzzler]

Probably in bad taste for me to mention but I've been close to 18 grains of 2400 in a Ruger .357 Blackhawk with a 180-ish bullet. Nothing looked weird afterwards but I'm not sure that or a 19+ grain L'il Gun load with a 180+ in .357 is a good idea again for me either.

240 grain bullet is not heavy at all for a .429 magnum but that's still a stiff load of slow-ish powder.

I don't have many books but none of them agree on hardly anything.

[Blind Hawg]

36,000 psi per SAAMI. My 1987 Speer #11 says "none of these loads exceeds 43,500 psi. I need a new manual. Why the discrepancy?

[GasGuzzler]

Powders aren't the same as they were 33 years ago and neither are the lawyers.

[Archer]

36,000 psi per SAAMI. My 1987 Speer #11 says "none of these loads exceeds 43,500 psi. I need a new manual. Why the discrepancy?

Data has been presented in various ways over the years. Internal ballistics has been a black art and evolving science for the past couple hundred years or more. Copper Units of Pressure are NOT the same as Pounds per Square Inch. Do NOT confuse CUP listings are equal to PSI listings. Pressure transducer measurements typically reported in PSI are generally considered to be more accurate and more repeatable than CUP measurements.

SAAMI Spec:
https://saami.wpengine.com/wp-content/u ... g-Copy.pdf

Page 14 (PDF page 23) lists CUP pressure limites for .44 Magnum.
Page 54 lists chamber and cartridge drawings w/ dimensions.

Page 22 (PDF page 31) lists PSI pressure limits for .44 Magnum.

I do not know if the European standards (CIP) differ from the SAAMI published data for .44 Mag or not. I do know that SAAMI specifications for some European rounds may be lowered in deference for well used military firearms that may have made their way to the U.S. market. (In other words attempts at lawyer proofing the round in question at the expense of performance OR 'in deference' to firearms that may have been produced before propellant enhancements may have raised the potential pressure of a given round. (Say 6.5x55 Mauser, 8mmx57 Mauser etc.) Meanwhile the CIP ratings assume you aren't stupid enough to put maximum loads in a weapon that's not in good repair or that you haven't worked up a given load from a safe level watching for problem signs.

In addition, MANY manuals publish heavy load data designated for use ONLY in premium weapons know to be particularly strong actions. These generally include data for heavily build Ruger or Freedom Arms revolvers or potentially for use in TC Contender/Encore weapons that are known to have robust actions and no cylinder gap to worry about. Such loads are typically considered safe for use in those weapons KNOWN to be overbuilt and are usually recommended with restrictions against their use in lessor weapons, weapons that are not in perfect repair and condition and may be listed as for use ONLY in virgin brass. Those load exceed specifications for the caliber. (Hornady for example lists a T/C only load that exceeds the load your initially posted load at 22.8 grains with a WLP while Lyman's T/C-Encore loads max out at a mere 19.5 with a CCI 300 primer.) Care must be taken not to mistakenly use one of these 'special' loads when you are not loading for a firearm that is over designed or when you want to stay within spec limits.)

Current Speer data is available online their 240 grain .44 Magnum Rifle loading data can be found here:
https://reloading-data.speer-ammo.com/d ... um_240.pdf
Note they max the charge weight at 21 grains with a CCI 300 (standard large pistol primer) for 2400 (and that primer choice changes dependent on powder.)
(They do not list 240 grain handgun data online except for 240 grain LSWC possibly because it is the exact same pressure limits for handguns and rifles.) LSWC data:
https://reloading-data.speer-ammo.com/d ... 0_LSWC.pdf

BTW General search for Speer data starts here: https://reloading-data.speer-ammo.com/reloading

I also have two Speer manuals in my reloading library:
The 12th edition limits 2400 at 17.7 grains for 2400 using CCI 350 primers.
The 15th edition limits 2400 at 21 grains using CCI 300 primers.
Note the shift in the primers from Magnum to Standard over the years.
Max pressure is listed at 36000 PSI or 40000 CUP.

[Blind Hawg]

I would have thought the primers would have shown some signs.