Hornady 115 gr XTP HP loads #35540

[mofosheee]

Hello Forum;

I'm using AA#2 for Hornady 115gr HP's.  This particular bullet / powder combo is not listed in the Western Powders load manual.  

Am I correct in understanding the following as a general rule for all reloading?

"for a particular powder one can safely use data for the same weight FMJ as long as they start about 10% below maximum and work up to a safe load"

The COAL's for my barrel plunks fine at 1.075" and anything longer doesn't work.   Published COL is 1.100  which throws everything out the window and puts me in unsafe territory

(or am I overthinking?)

 

From the Western table; 115 SIERRA FMJ 3.7gr  971fps 4.6gr 1,088fps  34,202psi 1.100COL

 

Thanks all!

 

[AHI]

YES

[MemphisMechanic]

You’re thinking correctly. Start at 10% under max and let a chronograph be your guide.

[mofosheee]

Thanks again!

[BC17A]

This page from the Hornady manual might help.

[MemphisMechanic]

Also I think you’re up to the same thing I’m up to. I’ve got 600 total rounds to load with 147 and 124 JHPs for “rainy day” ammo. 

I’ll be running longshot in mine, simply because it’s the only slower-burn powder I have on hand. 
 

We won’t talk about charge weight. +P stuff is something I tend to leave off the internet.

[mofosheee]

Thanks BC17A and Memphis for the great info..........was unable to find the published Hornady data that you attached. 

I'm relatively new to reloading. My approach to reloading is to scour the net for published data (prefered) ask questions.

The range where I can use a chrono is temporarily shut

 

One looming question...........

looking at the Hornady chart attached,  Why is it not preferable to max out the COL for any particular barrel?

I can get dummy  Hornady 115gr XTP HP bullets @ 1.16" to chamber and eject just fine in a 9mm.   The Hornady chart shows 1.075"Yes I realize velocity changes

[AHI]

#1 the length listed is the length they tested

#2 the length listed should fit in all guns chambered in that caliber. Notice I said SHOULD 

      did not say would.

#3 provides optimize bullet pull retention.  Thar fore optimizes pressure for a "clean" complete burn or the

      propellant (powder)

#1 and#2 are the main reasons

Edited March 24, 2020 by AHI

[mofosheee]

Then 1.075" it is.  Thank you

[zzt]

On 3/24/2020 at 8:39 AM, mofosheee said:

looking at the Hornady chart attached,  Why is it not preferable to max out the COL for any particular barrel?

 

Lengthening the OAL over the published load data does two things.  It reduces pressure and velocity.  Decreasing OAL from published increases velocity and pressure.  For max and +P loads, be very careful.  .025" shorter OAL in a max 9mm load is a significant difference.  In a PCC or a gun with an unsupported chamber, I would quit well below max (.3-.4gr). 

 

If it were my barrel I'd spend the $10 to get it throated so it took the longer OAL.

[mofosheee]

Thanks for the info zzt

Understand the OAL issues you cited.  Trying to stay out of the no go zones.

And yes, I intend to send barrel out as soon as things settle down.  

[MemphisMechanic]

Also, someday you might buy another gun or give some of the ammo to a friend. This is the kind of ammo that you want to feed in everything.  

[mofosheee]

1 hour ago, MemphisMechanic said:

 This is the kind of ammo that you want to feed in everything.  

      I'm seeing that.  Thank you!