Manuals start and max loads are way different

[ikie]

I am new to reloading. I checked with Lee's bool Modern
Reloading 2nd edition and it has for a 124gr. bullet XTP useing unique powder that the start grains is 5.1 and the maximum is 5.8.
I also checked with Hornady's book 7th edition and it has using unique stating at 4.0 and max at 5.0. I was wondering what starting load should I use. Don't wont to start at the max load. thanks for any help.
It is for a 9mm glock.

 

[Sam1911]

Maybe this is a trick question, but you should probably start with the load they so helpfully named a "starting load."

 

[Doc7]

From the OP it seems like one book has the "Starting Load" (5.1) as higher than the "Max Load" (5.0) of the other book, Sam1911.

I have neither books nor experience here so cannot help.

 

[Sam1911]

Ah HA! Yes, ok...sorry it didn't make sense on the first reading.

You can start at 4.0 and work up.

 

[JRWhit]

As informed by others here, Lee's book has a list of manufacturers data. I would check with what's comparable on Alliants website. Most likely it will have data for Speer bullets but it gives you a baseline. Find a middle ground between listed or if unsure start with hornady's starting load and work up from there.

 

[JRWhit]

http://www.alliantpowder.com/

Here is there address.

 

[ikie]

Thanks for the quick and good advice. I think I will start at Hornady's low start load and work up.

 

[James2]

The manuals show what the load developers found in their testing with their loads and in their test guns/barrels. There are going to be differences.

It is our responsibility to work up our own loads in our own guns. As always, start low and work up, looking for signs of high pressure as we go.

Yes, you will find lots of different loads if you want to look around. I prefer to use data from the maker of the bullet if it is available. Check their website.

Quite a diff in your two sources. I would be tempted to start around 4.5 gr.

 

[Jim Watson]

Just to add to the general hilarity, Lyman shows 4.5 - 5.0 gr Unique for 124 gr 9mm.

 

[taraquian]

I just made a batch of 124 XTPs using LEE data verified by Alliants data, nothing blew up. Yet.

 

[oneounceload]

I would go by the powder maker's website - it is the most up to date, they have the pressure testing equipment, and it is their name and reputation on the line

 

[gamestalker]

Providing both books reference the same bullet and powder combination, either start load will suffice just fine.
GS