Confusing .45. Colt manual data

[goathollow]

I'm looking to load 200 gr RNFP with Unique powder. I'm looking at the Hornady and Lyman Manuals as well as the Alliant web site. Hornady shows a starting load of 5.8 grains and max load of 8.6 grains. Lyman shows a starting load of 8.6 grns and a max load of 9.6 grns. The Alliant website simply shows 9.5 grns. I can see minor differences from manual to manual but Hornady's max load I'd Lyman's starting load. What am I missing?

 

[rcmodel]

What are you missing? Hmmm?
Well for starters, my Hornady manual is missing a 200 gr RNFP bullet??

It does show two 200 grain SWC's though.
But they are soft-swaged tumble lubed bullets, and won't take any pressure or velocity to speak of without severe leading.

Lyman shows a true cast & grease groove lubed RNFP bullet, made from Lyman #2 alloy, which will stand much more pressure and velocity.

Alliant data I have shows only a 200 grain LSWC, not a RNFP.

And you always reduce the single MAX load shown by Alliant by 10% for the starting load.

rc

 

[goathollow]

Ok, I should have started by saying I'm fairly new to reloading. I generally understand the difference between hard and soft lead bullets but I didn't realize a SWC was that soft. The difference now makes sense.

Is it safe then to presume that the LSWC is harder and similar to a LNFP?

Thanks

 

[rcmodel]

No not at all.

It's safe to assume soft-swaged LSWC bullets Hornady & Speer sell and show data for (in the Hornady & Alliant/Speer manuals) are softer then the real Cast bullets in the Lyman manual.

Hornady & Speer only sell soft-swaged tumble lubed pistol bullets.

Lyman only sells bullet molds, and you can cast & grease lube your own bullets harder then woodpecker lips if you want them to be that hard.

The Lyman manual also tells you what alloy each bullet tested was cast from.
There is an alloy hardness chart on page #81.

At any rate, the Lyman is the only manual you mentioned with RNFP data for the RNFP cast bullets you apparently have.

rc

 

[goathollow]

Ok got it. I will pay more attention to the type of bullet in the future. One more question if you don't mind educating me. If the SWC (Hornady) and LSWC (Alliant/Speer) are of similar hardness (or the lack thereof) why does Alliant show a powder charge that is 10% higher the the max load of the Hornady manual?

Harder than woodpecker lips....that's hilarious!

 

[rcmodel]

Who knows.

I do know Speer, which is also owned by the same group (Alliant TechSystems (ATK)), that owns Alliant, has never been as conservative on load data as Hornady in most cases.

You will find Hornady MAX loads are almost always lower then data from other reloading manuals.
Part of that is the unique shape of Hornady bullets, which often have more bearing surface / friction.

But part of it is, Hornady data is just generally more conservative then other sources.

Notice the difference in bearing surface between a 200 LSWC and a 200 LRNFP.

Photos courtesy of Missouri Bullet Co.



rc

 

[goathollow]

Thanks for the education. It is quite helpful!!

 

[GaryL]

One of the other variables that RC didn't get into with reloading data is some will use a standard test barrel and some develop their data on actual firearms. So you can see different results all else being equal.

Cross referencing can be confusing, but it can also be educational.