XTP vs Jacketed

[ivan7382]

Im new here and also new to reloading. I have a question about something in the manuals I have been refering to. Is the load data for XTP bullets the same as a same weight Jacketed bullet (i.e. 158 gr XTP and a 158 gr JHP)? The reason I ask is they dont list the use of the same powders in the two different types so what if I wanted to use the same powder with both types of bullets?

 

[strat81]

XTP is Hornady's JHP pistol bullet designed for expansion. Start at the minimum and work up using JHP data.

 

[FieroCDSP]

It largely depends on what reference you're pulling from. That's why most of us have three, four, or five references to go from. What caliber and weight are you loading for, and what powder do you have availiable? Chances are, someone on here has loaded an XTP for it. Also which manual you're using would help.

One reason you'll find some bullets don't have a powder listed is space/pressure constraints. As your availiable case volume decreases, you'll get higher pressures and/or different burn characteristics. So a powder that might work for a 155grain bullet might not work for a 180, if not dangerously then efficiently.
Lead also has different characteristics from jacketed. Too hot a load and a softer alloy bullet will start to melt on the back end and lead the barrel considerably.

Also, these listed loads are tested in a lab environment with a specified set of variables. That's why you'll see the max load pressures being listed as being only recommended in the test barrel.

+1 on the post above also.

 

[ivan7382]

I have been using the Loadbook USA for 357 Mag and the Lee Second Edition Modern Reloading Manual. One thing that makes me ask about the difference is that in the back of the Lee book it says that XTP bullets are different than other bullets and that they require a different load. So I didnt think that I could interchange data for regular JHP and XTP load data.

 

[FieroCDSP]

Lee data is pulled from other sources. The listed loads are probably for the best expansion in those weights. There's no reason you can't use the starting data for the next higher weight XTP listed and then work up. Or just use the jacketed data, which should be pretty close. Use the starting load with those as well, as different bullets have different lengths and seating depths.

 

[Mark whiz]

I've used JHP loading data plenty for working up XTP loads, never any sort of problem. The only thing you might find is that different nose shapes and hollow point cavities can like slightly different powder levels. For instance the wider-cavitied Gold Dot bullets I've used like slightly lower powder charges than XTPs.

 

[strat81]

I load my XTPs a bit shorter in 9mm because of the nose shape.

If you like Hornady bullets, get yourself a Hornady manual or check the Hornady section of your Loadbook.

If you can't find the exact XTP/powder combo you have, use JHP data for the same weight and start at the minimum load given. Check your brass and primers for pressure signs as you work up.

 

[rcmodel]

For instance the wider-cavitied Gold Dot bullets I've used like slightly lower powder charges than XTPs.

That is because Speer Gold-Dots have Electroplated jackets, and XTP's have normal gliding metal jackets which are both thicker & harder.

It has nothing to do with the HP shape.


rcmodel

 

[The Bushmaster]

Load all JHP (not plated) bullets the same as your manual says. Just start at the lowest powder charge weight and work up watching for high pressure signs (not flattened primers).