jsp, jhp, jfp same weight

[Encoreman]

I have seen various load data and some confuse me. The question is say I'm loading a 158 grain jacketed bullet in a .357, does it matter whether the bullet is a jsp, jhp, or jfp using the same powder charge. I understand if it is a lead bullet that the powder charge would change. Thanks for your help. Mac

 

[steve4102]

Yes and no. Yes,You can use load data for different bullet designs of same weight. No, the OAL may not be the same. Always start low and work up.

 

[gamestalker]

With regard to the powder charge I would say yes, it is OK. I've been loading like this for decades without problems and have read in my books that it's not an issue for the most part. OAL is another story. If the bullets have a canelure just seat and crimp at the canelure and you'll be OK. But as with any new bullet you haven't loaded yet, start at the low end of the data and work up to where your happy.

 

[DWFan]

The first thing to look at is the seating depth. Don't take the cannelure location for granted. An example is the .357" 158gr bullets from Hornady and Sierra. The XTP HP and FN have the same seating depths and can use the same data but will give different overall lengths. The 158gr Sierra JHC seats deeper than the XTP and will generate higher pressures; possibly too high if maximum charges are used. Conversely, the 158gr Sierra JSP seats shallower than the XTP's and will lower operating pressures. The Sierra JHC and JSP will give the same overall length, however.

 

[noylj]

As with any bullet, period, start with the lowest starting load and never assume.
Most older manuals grouped all their jacketed bullets together for load data and, some, even included their lead bullets (I believe Speer did this until, maybe, just recently).
Learn how to find the best OAL for your gun and how to work up a load.