Problem with load data for 460 S&W Magnum

[ngnrd]

I picked up a 460 S&W Magnum a few weeks ago, and I can tell you that there is definitely some odd reloading data out there for it. I'm going to have to be very careful working up loads for it.

I bought some 300g Hornady XTP-Mag bullets and Hodgdon's Lil' Gun powder to work up some loads with. But, having looked at multiple data sources, I discovered that there are significant differences in the listed starting/maximum powder charges between the different component manufacturers. For instance, the Hornady data for this combo lists charges between 29.3g and 38.4g. But Hodgdon lists the min/max for this combo at 40g and 44g.

That's right... The STARTING load given by Hodgdon is higher than the MAX load given by Hornady.

So... what do I do with that?

As a comparison, Hodgdon's data for their other powders listed for this bullet (Win 296, H4227, and H110) all overlap the Hornady data - some more than others. I can understand one manufacturer's data being more conservative than the other's, but the difference in the given loads for Lil' Gun has me baffled. I would think they would overlap at least some.

Is this something fairly common that I have just never run into before, or is it a rare case?

 

[buck460XVR]

If the info from Hodgdon includes H4227, you are looking at old data, since they no longer distribute it. Some of the old data for the .460 S&W is all over the place. Hodgdon seems to be aggressive and Hornady seems to be a tad more conservative. In my XVR, I tend to stick closer to Hornady's data more so than Hodgdon's. First off, the .460 is a powerful enough round that one does not need to hotrod it for it to be effective. Secondly, my XVR is one of those with tight throats and it tends to not like hot loads. The Hornady XTP-MAGs(both 240 and 300 gr) are great bullets for .460 applications as are the Speer 300 gr Deep Curls. Stay away from bullets intended for .45 Colt velocities unless you are loading down to prevent excessive forcing cone and top strap erosion. Speaking of excessive forcing cone and top strap erosion, have you heard of the suspicions from this occurring with the use Lil' Gun? A coupla years back, Lil' Gun was almost the Holy Grail of magnum handgun powders, but lately because of these suspicions, I hardly hear of it's use in revolvers anymore. Since I never got the claimed velocities and it's accuracy in my handguns was never as good as H110/W296 and IMR4227, it was easy for me to discontinue it's use. Since then I have gotten to where I use IMR4227 almost exclusively for my XVR. It gives me great accuracy with 300 gr pills and it is not near as temperature sensitive as H110/W296. Something to think about if you will be shooting your .460 like me, in temps that range from 90* to -20*.

 

[56hawk]

Do any of your sources list the test pressure? SAAMI max for the 460 is 65,000 psi. I ran into this problem with the 500. SAAMI max is 60,000psi, but the loads in my manual only went up to 45,000 psi. I was able to load seven grains over max with no signs of pressure.

 

[ngnrd]

If the info from Hodgdon includes H4227, you are looking at old data...

That's interesting, because I pulled the data straight from Hodgdon's online Data Reloading Center. I would think that if they no longer considered the data to be valid, they would pull it.

Anyway... Thanks for the heads-up about the possible flame cutting issues with Lil' Gun. The previous owner gave me an unopened can with the sale, so I thought I would give it a shot.

I also have a box of 300g Speer Deep Curl "Casull" to load up, and the data I've seen for Lil' Gun with the Speer bullets is more in line with the lighter Hornady data. I just don't understand how the Hodgdon data can be so much hotter. It's baffling.

 

[ngnrd]

Do any of your sources list the test pressure? SAAMI max for the 460 is 65,000 psi.

Hodgdon lists pressure data, but not what device the load was tested in (revolver, test barrel, T/C, etc). Their 40g starting load shows a pressure of 46,300 psi, and their 44g max load has a pressure of 53,600 psi. My other sources don't list pressures.

I'm not necessarily looking at running super hot loads. I just want to be safe while doing my work-up.