Which is best in a .357 for ACCURACY? .38 spl cases or .357 magnum?

[Conditor22]

Lee 358-158-RF 13 bhn PC'd sized .358 seated to the crimp groove
over Lyman #4 max 2400 load in 357 cases, 1 hole group at 50 yards out of an IMI Timberwolf.
I quit testing

[wv109323]

I think you can get excellent accuracy with both. I think the difference will be so insignificant that you can not tell the difference shooting off hand. The .357 cases will eliminate chamber cleaning.

[RED BEAR]

I would have to say 357 cases. But will also say i seriously doubt you could tell the difference. I certainly don't shoot good enough to.

[StrawHat]

I competed in PPC for about 14 or 15 years. Shot good enough to get into and stay in the Governors 20. My main competition revolver was a Davis built S&W Model 64 with a slab sided barrel and a bunch of stuff not seen. My Distinguished Revolver was a S& W Model 686 with a 6” barrel.

I shot reloads in practice and Federal factory for competition until the day I realized my practice scores were equal or perhaps an X higher than competition. Some of that is normal but after a year, I just went with reloads. I used a cast DEWC in 38 Special cases. I do not recall the lube but I only lubed and groove. Primers were CCI and cases were degraded by head stamp, I believe I used Federal in competition. I seated the boolits long to get into the throats.

The point I am trying to make is the scores with the 686 (chambered in 357) were good enough that at some point I retired the Davis gun and just shot the 686. So, at least in those two revolvers, three decades ago, the 38 Special case shot great from the magnum chamber.

Kevin

Today, either of those revolvers would tire me out!

[Lance Boyle]

Lathesmith, a member of this forum, can make an excellent powder through expander (powder funnel in Dillon parlance) for the Dillon powder dies. The powder funnel is a game changer for loading cast bullets, including wadcutters. You can ask for the dimensions you want but essentially the key is an expander that expands the case to a larger diameter and to a greater depth in the casing. Add to that a Lyman style "M" die "step" to help align the bullet in the casing and you'll have an outstanding set up.

If you have a lathe and some suitable round stock, you could probably make one yourself. It's not a complex part.
If you'd rather have one made, Lathesemith's work is top notch and I highly recommend him.

His work is very good, I bought items from him before, star size dies from him before I bought the lathe. I have been contemplating making the special wad cutter powder funnel, I have the tool steel rod stock on hand. It’ll be easier than the custom expander I made for my RCBS .38-55 cowboy dies. One of my first projects beyond fooling around. I admit it took me three tries to get the threads right. Anyone need a .382 expander with reverse threads? Yea, I did that.