444 Marlin load question. . . . two books are much different

[R00KIE]

I loaded my first batch (18 rds) for my new 444 today. . .

The only powder I could aquire here was H4198
The only bullets I could find were Hornady 240gr XTP
I have once fired Remington brass and I used Remington 91/2 primers


The discrepency here is in my two load data books. . .
The Hodgdons book that came with my Lock and Load kit shows H4198 49.2gr. for a 240gr bullet and that shoots 2499 fps
But My hornady 7th edition shows H4198 and 240gr XTP for a maximum load of 46.5gr 2300 fps . . . and thats the red top pressure box
Both of these using a 24" bbl of course.

So my question is. . . Is Hornady being "safe these days" or is the Hodgdons book just way out of line? Any thoughts for me?

 

[Sam1911]

Well, Hodgdon makes the powder (or at least imports it?) so I'd trust them...

Actually, you'll find discrepancies between load books of a few percentage points of charge weight for almost any cartridge you'd care to try. There are too many variables in the test procedures all the different manufacturers use to make perfectly repeatable recipes, down to the tenth of a grain -- or in larger rifle cases, even down to a few grains. Everyone who gets into reloading notices this. Most find it a little unsettling at first, but we come to expect it.

Pick a starting load somewhere near the bottom of the lower range and work your way up in small steps. Watch your accuracy, of course, but also look for pressure signs. Sticking cases and flattened primers can indicate dangerously high pressures, but they usually don't show up until you're in the danger zone. Watching your velocity is generally the safest route. If you get a steady, regular, increase in velocity as your charge weight goes up, things are more likely to be ok. If you see that a load jumps WAY up in velocity, STOP. And never exceed the published maximums.

-Sam

 

[Randy1911]

They are both correct. The reason for the difference is the method and componets used to arrive at the result. Start with the lower of the two and work up slowly and watch for pressure signs. All boois will differ because of this. My Lyman #48 shows a max load of 49.0 for that powder and bullet.

 

[Kernel]

This illustrates the need to reduce by 10% and work up to your own maximum. Never shoot someone elses max load without first working up to it.

Published loads will vary. It’s not uncommon for ten sources to show ten different sets of numbers. There’s so many variables, and reloading isn’t that of an exact science.

In your particular example I wonder how COAL may play into it. I believe the 240gr XTP has two crimping grooves (I know the 300 gr .429 XTP does). If that’s true, it’s possible the load with more powder used the second groove - the groove that would produce the longer cartridge.

Longer cartridge = more room for powder = higher velocity. Just guessing. Might be nothing of the sort.

Be advised there are Contender only loads published for the .444 Marlin. Stay away from those, IF you're shooting a lever action.

 

[zeke]

Another reason to have multiple manuals/references. Even the manufactures manuals make mistakes, that carried through for years. In the 444 rifle, hodgen appears to have reversed h4198 with imr4198, after the 4th edition. Ya might want to also check their 444 encore pistol loadings, particulary the differences between imr-4198 and h-4198.

The latest Speer manual perpetuates a similiar apperent mistake with 748 charges in the 30-30 rifle, using the 130,150 and 170 fnsp's.

Just reinforces the need to start low and work up, using multiple references.

 

[R00KIE]

good info, thanks guys!