What to do when 231 and HP-38 are NOT the same?

[matteekay]

Howdy!

 

I just picked up some Eggleston Munitions 147gr LRN bullets to use in .38 Special cases. It's been hard to find load data for this weight and case; there's a lot of 148, but it's all for hollow base wadcutters (which require a unique load due to the bullet skirt and the extra room in the case). Lo and behold, though, I was going through my "load book" (that's basically a photocopy of a bunch of manuals - you know the one) and found a Lyman lead bullet that's nearly identical. It even has load data for my preferred powder, HP-38/231. However...

 

 

Looking at the lower chart, the two show different charge weights and max charges. This is probably from a very old manual... does anyone know which would be more accurate for today's iteration of HP-38?

[superdude]

Use the most current data available, which is available at the Hodgdon website. 

 

http://www.hodgdonreloading.com/

[matteekay]

3 minutes ago, superdude said:

Use the most current data available, which is available at the Hodgdon website. 

 

http://www.hodgdonreloading.com/

 

Thanks, I started there but they don't have a bullet that's close to this one. Aside from the afore-mentioned HBWC, all they have is a 146 JHP - I don't think I should use that load data to throw lead.

 

For the record though, the max they list is closer to the HP-38 measurement about. It's also saying it's a slower velocity. 

[leewongfei]

Loading books have become a bit more conservative over the years with how much powder to use. Additionally, the bullet hardness isnt being taken into consideration. One manufacturer could be printing data from soft lead, rather than hardened lead. this is why most people recommend you start off with a lower charge and work your way up.

[anachronism]

Use the data for  Lymans 358212, which is a 146 gr cast bullet. You already have it, and the data includes pressure data as well. Your bullet manufacturer shows some data for 38 Spl, call them and ask them for data. It's a weird weight for a 38 Spl RN.

[RePete]

Before Hodgdon got the WW powders, HP 38 was a bit different.  It was a blend of different batches of WW231.  Since it is the same powder.

 

You must be careful when looking at old manuals.  Go to the powder manufacturers web site.

 

Also, contact the bullet manufacturer and ask them.