I'm Confused

[tipiguy]

I am reloading for a .38 special.  I am using Alliant Bullseye powder.  On the Alliant website it said to use the following as a max load:

148 grain LWC  =  2.8 grains
158 grain LSWC = 3.6 grains

Does this sound right?  I always thought the heavier the bullet the lighter the charge because of the increased pressure.  Any advise would be helpful.

tipiguy

[Dusty Miller]

I think you're right, Tip.  Don't use that data until you get more info.

[JohnDY]

Could it be because a wadcutter is loaded flush with the mouth of the case and a semi-wadcutter is loaded with a portion of the bullet outside the case leaving more room in the case?

[John Traveler]

Gentlemen:

The loading manual writers try to discourage the practice of loading red-hot .38 special watcutter loads.  

One reason is as as JohnDY suggested.  A flush-seated wadcutter will develope more chamber pressure than the same weight bullet conventional nose bullet seated outside the case

The hollow-base wadcutter is intended only for target shooting velocities.  In the past some writers suggested loading to maximum velocity with  either conventional or inverted hollowbase wadcutter bullets to give impressive mushrooming effect.  This would often result in blown skirts and forcing cone bore obstructions.

I suggest that the standard 2.8 grain Bullseye loads are maximums to avoid the potential for bore obstructions.

[Flint]

The wadcutter is intended to be a target bullet, so it is to be driven no faster than necessary to get to the target.  Particularly a Hollowbase wadcutter will deform if driven much over 800fps.  The 158 grain bullet is intended for more serious work, and can be driven as fast as the bullet material and gun can put up with....

[Questor]

Those loads look reasonable to me. But that's why it's good practice to have multiple load manuals.  The comment about the target wad cutters is right.  That's a light load.

[Leftoverdj]

Flush seating WC reduces case capacity and increases pressure, hence the lighter charge. You can blow off the nose of a HBWC and leave the skirt stuck in the bore if you get too happy with the charge.

Nevertheless, 2.8 grains of Bullseye is a mighty light charge. It was a popular target load for many years, but almost as many shooters used 3.0 or 3.1.

If you are using solid base WCs, there is much hotter data available. Lyman Cast Bullet Handbook would be a good place to look for that. Personally, I adjust the charge according to the pistol I am using to get 800 fps.