454 Casull Bullet Selection

[ZGunner]

I'm loading for a 20" barrel Rossi M92 using H110. I'm noticing some load velocities for lighter bullets are starting at 1800 fps but the bullets are only rated for 1500-1600.

I've zeroed in on the 300+ grain Cast Performance Bullets because the data I find is within the bullets' velocity rating.

My question is, what are my options with the lighter(240-250gr) projectiles and how much speed will I gain from the longer barrel.

 

[TimSr]

Rating bullets for speed is done simply because most loaders cannot measure pressure. When they rate a bullet for speed, it is based on their guess as to what it will be loaded in. If someone offers a 45 bullet that is rated for 1500-1600, they are assuming it will be shot out of a pistol. Even though you gain quite a bit of velocity from your 20" barrel, the pressure is still the same. If the load data suggests load at 1500-1600 from a pistol, the same bullet over the same load should work fine in a carbine, even though velocity will be higher.

Terminal performance with expanding bullets is based on velocity on impact, but I assume that is not what you are looking at with cast bullets.

 

[Cheesemaker]

I always load Hornady's XTP MAG bullets (240gr and 300gr)in my 454's and 460S&W. The MAG is important as they are rated for higher velocities than the non-MAG.

Edit: The 240gr XTP MAG bullets are rated up to 2200fps - according to the Hornady website.

As far as velocity increase - hard to say exactly without chrono'ing. As a guess - I think you will see an increase around 300fps to 450fps over a 7.5" barrel. (This is the "ballpark" delta when looking at the Hornady manual and comparing a 240gr 44Mag 18" rifle and 7.5" revolver load).

 

[ZGunner]

Thank you for the replies. I'll look into the XTP MAG. Looks like I really need to get a chronic if I'm going to get serious about this stuff.

 

[Mauser69]

I do not know about the .454, but I have seen a number of comparisons of .357 load speeds between 20" rifles and 6" handguns - the speed differences vary a lot depending on the powder and specific bullets used, but they generally show a 500 - 700 fps increase for the lever gun, with really heavy bullets only getting a boost in the mid 400s. I do not know how that data from the .357 would compare with a bigger caliber, but I suspect the gain would be less.

If you check other load data sources for the .45 or .44 Mag, you might find comparisons. For example, Nosler lists data for the .44 in both handgun and rifle, but I do not think they use a revolver for the handgun, so those speeds might be artificially high. Handgun data tested with a 8.25" Douglas barrel, and rifle data tested with a 18.5" Ruger barrel. Various powders with same charge and bullets generally showed less than 200 fps increase in the longer barrel (all Nosler data is for jacketed bullets).