Can someone explain this load data to me?

[0to60]

I have a box of 148 grain double ended lead wad cutters for .38/.357 and I'd like to load them up with some Win 231 that I have left over. I'm looking at winchester's published load data (http://data.hodgdon.com/main_menu.asp), and it shows a max load for .357 of 3.4 grains, but for .38 the max load is 4.0 grains. Why would the max load for .357 be lower than the max load for .38?

Consequently, I loaded 100 rounds with 3.2 grains. Now I'm wondering if this load is too light and I'm gonna run into leading issues. Unfortuantely, I don't know the brinell hardness of the lead.

 

[Jim Watson]

Beats the dickens out of me.
I note the .357 load gives about the same chamber pressure as the .38 although I can't see why it would. Loads for HBWCs are limited by bullet design not gun strength.

I have loaded several boatloads of .38 wadcutters at 3.2 gr W231. and see no reason to go higher.

You have more leeway with double ended wadcutters, if you want to use it.

 

[MichaelK]

I could suggest a couple of reasons. First, because the .357 cartridge is longer, and the full bore diameter of a wadcutter is sticking out of the cartridge, it may have been resting against the cylinder throat, which might raise pressures a bit.

Alternatively, they may have done the test in two different guns, with perhaps the .357 with a slightly tighter bore/chambers.

 

[Steve C]

The data you are looking at is for a LHBWC or Lead Hollow Base Wad Cutter so the data is lighter than what you can shoot using a flate base DEWC. The main difference between the 2 loads is the use of a WSPM primer for the .357 mag and a WSP primer for the .38 spl. Notice how the mag primer drives up the pressure in the lager volume case of the .357 mag even with .6 gr less powder.

If you use the "print" function on the website you will see more information on the test barrel and primers used.

 

[Smokey Joe]

Of wadcutters, and primers...

I shoot bullseye pistol with a .357 magnum revolver, so I like to use .357 cases rather than .38 cases.

Probably haven't loaded as many as Jim Watson, but at least one full boatload of target rounds.

My load for 148 grain DEWC's is 3.4 grains of Win 231, which does very satisfactorily. However, I NEVER have used magnum primers with this very light target load. No reason to, IMHO.

Have used CCI, Rem, and Win small pistol primers, and they all worked the same. No observable difference in accuracy.

Target pistol bullets are normally made quite soft, as the lead is cheaper than antimony to harden them. At "target" velocities, leading hasn't been much of an issue for me. (That is, 700-800 FPS. If you were to shoot the same bullet at, say, over 1000 FPS, it'd probably lead the bbl. like crazy.)

I use mixed manuf. brass, but all trimmed to the same length for crimp uniformity.

Legal weasel note: I have mentioned a particular cartridge loading that works for ME, in MY firearm. I'm not recommending it for your firearm; you will have to work up your own load.

 

[918v]

The intent is to keep the velocity of the HBWC to 800 FPS and less so the skirt don't blow off and cause a bore obstruction.

A magnum primer will drive up the velocity and pressure, so a reduced charge is necessary.

 

[rcmodel]

the .357 cartridge is longer, and the full bore diameter of a wadcutter is sticking out of the cartridge, it may have been resting against the cylinder throat,

Nope.
Hodgdon lists the OAL as 1.290".
The .357 mag MAX case length is also 1.290".
So they tested seated flush with the case mouth.

Besides that, any number of .357 cast bullets have full diameter driving bands sticking out of the case when seated to the crimp groove.

There is plenty of room in the chamber throat in any gun for a .358" wadcutter to stick out if it wants too.

I agree the use of a mag primer in the .357 data is the only logical explanation.
But I'm not convinced it would make that much difference.

I sent an email to Hodgdon yesterday asking the discrepancy between .38 Spl & .357 data.
If they answer me, I will post the reply.

rc

 

[Iron Sight]

It would be interesting to see an answer from Hodgdon on this.

Anxiously awaiting

I think they got some data mixed up?