HS-6 works wonders in .38 Special +P. But current published loading data is so watered down that it stops well short of the pressure limit.

Speer Number 8 (aka "The Atomic Manual") lists the starting load as 7.0 grains of HS-6 under 158 grain lead bullet. That load exceeds the lame maximum charge on current Hodgdon website. The Speer Number 8 maximum was 8.0 grains... I've tried it and it's full power no doubt.

There are those who go into a catatonic trance and scream when Speer Number 8 is mentioned. Fine. Speer Number 10, published in 1979 (back when +P actually meant something) writing in the .38 Special section, states "+P working pressure is 22,400 cup."

SAAMI later watered down the .38 Special +P specification. In its 2015 publication, "American National Standard Voluntary Industry Performance Standards for Pressure and Velocity of Centerfire Pistol and Revolver Ammunition for the Use of Commercial Manufacturers", the pressure spec for .38 Special +P was lowered to 20,000 CUP. The nominal velocity for a 158 grain bullet is listed as 880 fps from a 4" vented test barrel.

Based on the performance of some historical hi-speed factory loadings (158 grain bullet at ~1090 fps), the "new" .38 Special +P level is fairly weak sauce.

Take a look at the current Hodgdon HS-6 data for .38 Special with 158 grain cast bullet, and it stops at 16,200 CUP. Having tried Hodgdon's low pressure .38 Special HS-6 loads, the results are dismal - unburnt powder, low velocities, mediocre accuracy. It's obvious how watered down the Hodgdon HS-6 data is in .38 Special. No data is provided for +P loads with a 158 grain lead bullet. Why?

Oddly enough, Hodgdon decided to provide 158 grain cast bullet data for .357 Magnum: 7.0 grains of HS-6 gives only 15,500 CUP. Hmmmm, something fishy is going on here...

A little bit of analysis indicates that whether you intend to stay within the current 20,000 CUP +P limit, or the traditional pre-watered 22,400 CUP limit... you can increase the charge accordingly. Pop a magnum primer in the .38 Special case, and bump up the powder charge to normal levels and you have something really good. My personal HS-6 loads with 160 grain LHP bullets make 985 fps in 4" barrel revolver, and 900 fps in a 2" gun. The loads are very accurate and hit POA in fixed sight revolvers.

Buffalo Bore sells loaded factory ammo at these levels. Their choice of powder is unknown, but obviously the pressure levels are safe.

Note these pressure figures are for copper-crusher CUP, NOT transducer PSI. The numbers are not the same. Hodgdon still lists its 38 Special and 357 Magnum pressure data in CUP... I'm surprised because you are now able to see how weak these loads have become since the SAAMI downgrading. Once pressure figures are expressed in PSI, you have no way of comparing them to older CUP data.

As always, YMMV, and practice safe and prudent loading practices. Inexperienced reloaders should adhere to published data. What is acceptable in your guns is YOUR RESPONSIBILITY.

Happy trails!