.40 cal. Longshot data question

[gamestalker]

I load a lot of jacketed for the .40 cal., usually bullet weights between 150 gr. to 165 gr., and occasionally 180's. And I almost always use Longshot.

But something that has had me scratching my head. Longshot generally has a pretty broad charge table, 135 gr. through 155 gr. and the 180 gr. and 200 gr. all have a good wide range. But when you get to the 165 gr. jacketed, the table looks very strange, as follows.

The start charge for the 180 gr. is .8 grs. lower than for the 165 gr., and has a max charge that's .2 gr. higher than for 165's, both with jacketed HP bullets. And the table for 165's is only .5 grs., where as 180's have a 1.5 gr. table.

Would someone please shed some light on this for me. I've been using the powder / data for a long time with absolutely nothing but positive results, so I'm not concerned, just curious about this.

GS

 

[horseman1]

I load 40 SW as well and use Longshot for my hotter loads, too. I have never had occasion to load for 165gr jacketed bullet, but have looked/stared at the Hodgdon data enough to have seen this anomaly as well.

Nosler and Hornady dont make one, so I cant find any of their data. Maybe someone with the Sierra manual could add some value, if Longshot data is listed.

H1

 

[gamestalker]

Sierra doesn't show Longshot, nor does Hornady, Nosler, or Speer. Hodgdon is the only place I've found jacketed data with Longshot.

GS

 

[KansasSasquatch]

In that case, Hodgdon probably tried lighter charges and found the results disappointing, and didnt bother publishing the lighter charges. But give them a call, they're pretty good about answering questions about their data.

 

[Toprudder]

I'm interested in this thread as I reload 40, and recently picked up a pound of Longshot to try (in other calibers, too).

I have noticed anomalies like this with the Hodgdon data as well. I always cross reference with Speer and Hornady manuals whenever possible. Too bad they don't show data for Longshot in this instance.

 

[ArchAngelCD]

I load a lot of jacketed for the .40 cal., usually bullet weights between 150 gr. to 165 gr., and occasionally 180's. And I almost always use Longshot.

But something that has had me scratching my head. Longshot generally has a pretty broad charge table, 135 gr. through 155 gr. and the 180 gr. and 200 gr. all have a good wide range. But when you get to the 165 gr. jacketed, the table looks very strange, as follows.

The start charge for the 180 gr. is .8 grs. lower than for the 165 gr., and has a max charge that's .2 gr. higher than for 165's, both with jacketed HP bullets. And the table for 165's is only .5 grs., where as 180's have a 1.5 gr. table.

Would someone please shed some light on this for me. I've been using the powder / data for a long time with absolutely nothing but positive results, so I'm not concerned, just curious about this.

GS

I don't know where you got that data but it's possible the 165gr bullet is very different than the 180gr bullet. That sometimes happens like with Hornady HAP bullets.

Hodgdon has 165gr and 180gr bullet data for the same exact Berry's Bullet and the data looks normal.

165gr - 6.9gr to 7.8gr
180gr - 6.3gr to 7.3gr

I see the data for 165gr Sierra JHC bullet and the 180gr Hornady XTP bullet is probably what you're talking about. It seems the Sierra bullet is the misfit in the mix. I have notices Sierra JHC bullets are slightly different than XTP and Gold Dot bullets.

 

[Ex]

I always figured the higher charge was due to lighter/shorter bullet. Shorter means less bullet in the case which means lower pressure... if I read this correctly...?

 

[Rule3]

I do believe ARCH has summed it up well.

Pretty much different bullets =different test=different results.

 

[gamestalker]

Well, it maybe a different bullet thing. But I've used this same data with numerous other jacketed bullets, and nothing seems odd or unusual. The Sierra JHP appears to have an average cup & core profile, nothing about the way it sets down into the case seems any different than the XTP, or any other JHP.

GS