Load Suggestion For M66-4 in 4"

[Northrunner]

I recently purchased a M66. Fired 24 rounds of .38 through it before I even got it home. What a sweet revolver...
I've loaded rifle hunting rounds for years, but never any pistol rounds so now I need to go out and buy some pistol powder, bullets, etc. I generally try to find a powder/bullet combo that does well and stay with that so I don't end up with too many types of powder.
Can you suggest a standard .38 load and a little less than standard .357 load? Thanks...

 

[Forester]

4.5 grains of unique under a 158 grain lswc in a 38 case.

For the 357, I use 14 grains of 2400 under the same bullet. I would call that a full house 357 though. You might try reducing that load a bit but then you are not using 2400 to it's full potential.

 

[epj]

Depends a bit on whether you want a fairly light target load or something with a bit more uuumph. Unique is good for medium warm to fairly hot loads, not so good for light. Bullseye and 231/HP38 (same powder, different name on can) are long time favorites. They will go from one end to the other, but are a bit dirty loaded light. I use Clays for light to medium loads, 231 for heavier loads. Universal Clays is also a good substitute for Unique, probably a little cleaner. Check the Hodgdon wensite for exact load recipies.

 

[tbury]

My standard 38spcl paper punching load is 3.5 gr of Bullseye behind a 158gr lswc. This is a excellent target load at 75' or 100'. I agree with the suggestion of looking at Hodgdon's data site. Titegroup is another powder that will work well in this caliber. 2400 is a long time favorite for hotter 357 loads but I do not go there that often anymore.

 

[OKFC05]

Hodgdon Powder for 38 (HP38) is my standard powder for .38 loads. Having tried almost everything else--and a couple dozen different powders will get the bullet out the muzzle--I haven't found anything better suited for .38.
And a near max load of it in a .357 case behind a Speer 135gr SB bullet duplicates the factory Speer load, which is easy to shoot in a model 66.

 

[Spotteddog]

What everyone's already said!
Congratulations on getting what is arguably the most versatile K frame ever produced. Trouble is, she's SO versatile it almost allows for TOO many loading choices! Wonderful gun!

 

[Wayne M]

A Hard 158SWC over 6.5gr of AA5 and a WSP at the back is a great hot 38 load. The same bullet over 12.5rs of AA9 and a Winchester SP will give you in the neighborhood of 1250fps in the 357 case and is not hard on the machinery.

 

[Bugs100]

3.1gr of Red Dot gives me 840 fps with 158gr cast

 

[Paul5388]

I have a M66-2 and I have never found a published load that would hurt it. Of course, I don't shoot a gillion rounds every time I break it out, like some are prone to do, and that may enhance its longevity.

I do avoid ball powders, especially with light bullets. I mostly use cast SWC bullets in the 158-170 gr range, whether it's .38 Specials or .357s.

For my guns that are .38 Special only, I shoot wadcutters, which reduces any possibility of mix ups with the hotter loads intended for the .357s.

 

[Skip Sackett]

HP-38 and Winchester 231 are the exact same powder and is ideal for the 38spl and light 357mag loads. If there was one powder that I WOULD use for everything, 40S&W included, it would be HP-38/W231. And I load for the 380 to the 45Colt!

I cast my own bullets too and have chosen a mould for the .357" firearms I have. It is a 160gr LSWC. Anything in that range will be great in your M66.

So, HP-38 and a 158gr - 170gr LSWC in either cartridge and you are good to go.

Plenty of data for those loads here: data.hodgdon.com

 

[ArchAngelCD]

I agree, W231/HP-38 is my favorite .38 Special powder. I reload more .38 Special ammo than anything else and I use W231 for most of it. I also like a heavier bullet when loading 38/357 ammo, I'm not a big fan of 110gr or 125gr bullets. I shoot mostly lead because of costs and lead bullets shoot just fine.

My powders of choice are W231, W540 (in the form of HS-6) and W296 when I load most handgun ammo.

 

[Swissman]

I'm a Accurate-Arms-Powder-Addict

This are the loads that let me win many competitions against my shooting-buddys.
(This means: "Free beer for Swissman" after shooting)

.38 Special:
Primer: CCI 550Small Pistol Mag.
Bullet: Speer JFP 158 grain (or JHP 158 grain is OK too)
Powder: Accurate #2, weight: 3 .8 grains
I give them a light crimp.


.357 Magnum
Primer: CCI 550Small Pistol Mag.
Bullet: Speer JFP 158 grain (or JHP 158 grain is OK too)
Powder: Accurate #2, weight: 6.1 grains
I give them a good crimp, but I do not torture the casemouth.

Using this data is at your own risk.

Swissman

 

[Joed49]

For a good .38 Spl load try 5.0 gr of Unique and a 158 gr jacketed bullet. For a midrange .357 try 6.5 gr of Unique in the .357 case. I rarely shoot a high energy load in my K frames anymore. But, when it comes to carry they are full house.

JoeD