Load variance between books with 115gr XTP

[dds51968]

I'm going to be loading SD rounds (not concerned with the legal part) and I'll be using 115gr XTP, Power Pistol, Federal primers and Winchester brass.

Lee 2nd edition says 5.9 - 6.7, Lyman 49th says 5.9 - 6.5. Lee has a OAL of 1.125 and Lyman has 1.090, they will be used in a CZ P09 and M&P full size. Why would there be a variance on max load and OAL between the two recipes?

I will be doing the proper work up in grains probably start at 6.1 and use an OAL of 1.125, 1.135 has always worked well with my 115gr plated loads in all 5 of my different 9mm's.

Can anyone tell me a recipe min/max/OAL from a different manual for the same components for comparison?

I realize it shouldn't matter, as I will need to develop a load that functions my specific weapon, it just makes me wonder about the variance.

Have a great Sunday folks.

David

 

[bush3755]

Different lots of a given powder will produce different peak pressures with a given set of other components in a given barrel.

The same set of components will give different pressures in different barrels.

Different pressure measuring systems will give different numbers for the same set of components in the same barrel.

Way too many different things out there to let all reloading data across many sources be the same.

Safest thing to do is use data with the lowest peak pressure or charge weights listed for the load.

 

[kcofohio]

Lee gets most of their load data from the powder makers. Alliant uses the GDHP for loads. Most of what Lyman uses is the Hornady XTP.

Chances are you have 2 different bullets in the data with different shapes and lengths.

As bush said, start at the low end and work up.

 

[JimKirk]

Even with identical guns ... maybe just a few serial numbers apart .... using the same identical ammo will yield different results....

That is the reason reloading manuals have a "starting" point .... they state that that load is safe in the gun they used to test it and the load "should" be safe in yours .... BUT the whole idea behind reloading is that YOU do the development of a suitable load in YOUR gun ... it is only a recommendation ... not 100% for every gun ....

 

[buck460XVR]

Go to the Alliant Powder webpage....they have a free online reloading manual there. As others have said, there is a multitude of reasons for conflicting data. As long as you start low and work your way up, all published sources have been tested and are safe.

 

[rg1]

Just for info:
Hornady 9th Edition 9MM Luger
115 Hornady XTP oal 1.075"
case Hornady---primer Win SP
Power Pistol
start 4.8--1000 fps-----5.2-1050----5.6-1100----6.0-1150---6.4-1200--and maximum 6.7--1250 fps.
tested in a S&W mod 39 4" barrel
Haven't tested any of these loads myself. Start low and work up.

 

[Sunray]

Lee gets all of their load data from the powder makers. Mostly Hodgdon. Lee tests nothing themselves. However, manuals will always be slightly different. Manuals reflect the conditions using the components and firearm given only.
Don't use cast data OAL included for jacketed bullets. A 115 grain jacketed bullet should be 1.169" OAL. According to Hodgdon, out of a 4" barrel. Mind you, barrels aren't the same.

 

[ljnowell]

Lee gets all of their load data from the powder makers. Mostly Hodgdon. Lee tests nothing themselves. However, manuals will always be slightly different. Manuals reflect the conditions using the components and firearm given only.

Don't use cast data OAL included for jacketed bullets. A 115 grain jacketed bullet should be 1.169" OAL. According to Hodgdon, out of a 4" barrel. Mind you, barrels aren't the same.

How can you assign a length to jacketed bullets by weight? Even identical weight billets of the same profile(like FMJ) will have different OAL because of ogive differences.

 

[Rule3]

If you are loading SD loads they I might suggest using a quality JHP bullet rather than plated bullets.

Use any of the big name HP (Gold Dots, XTP, Golden Saber etc)

A lot of research and development goes into JHP bullets.

Plated are just soft lead inside.

If the plated are just for practice then use the lower rates for the Hornaday data and use their max for the XTP bullet. They made and tested the bullet so use their data.

 

[dds51968]

Completely understood. I use LRN data for my Ranier, Berry's, and X-treme loads with titegroup. Thank you to all who weighed in.

David

 

[Gravedigger56]

Don't use cast data OAL included for jacketed bullets. A 115 grain jacketed bullet should be 1.169" OAL. According to Hodgdon, out of a 4" barrel.

I load my Hornady 115 FMJ and 124 XTP to a COAL of 1.160.

 

[gamestalker]

One thing I would like to add is, don't shorten the oal once you've developed the charge. This is true with any AL-ing handgun cartridge, but 9mm being the high pressure cartridge it is, oal changes with an already developed charge, can have catastrophic results when shortened.

GS

 

[dds51968]

To this point I've only set up my powder drop and seating die to accommodate this load. I will be making some test loads for a trip to the gun club in a couple of weeks to see what works best. I was loading all my target ammo at 1.135 with 4.2 of Titegroup with no problems, the OAL I'm going for will likely be around 1.125 or a scoatch less, I'll have to see how it actually functions though.

 

[gamestalker]

4.2 grs. of Titegroup for testing at varying oal's should be just fine for testing function. That charge falls into a pretty low table charge in most of my books, and below start charge in Hodgdon, so I think that would be just fine for testing oal function, IMO.

But what I was getting at, is once you've determined the full power self defense jacketed load you'll be running, I wouldn't go shortening the oal on that developed charge, without first taking the charge back down to a reasonable point, and then working it back up again at the new oal.

I know I've probably quoted this a million times, but Speer states that when they reduced the oal on an already developed load that was producing 28,000 cup, the pressures more than doubled to 63,000 cup.

GS

 

[TimSr]

Those differences in powder charge are pretty insignificant. You'll find much greater variations down the road that really make you search for a 3rd source.

OAL should be taken from a source that is using the exact same brand and type of bullet. What you are looking at is seating depth, and OAL is the most convenient way of measuring that provided the bullet length is known. If you cannot find a source for your specific brand and type of bullet, look at the seating depth in a known, in spec, round.