squib festival w/ 2400 and fiocchi primers

[Boolseye]

Have been loading some 124 grain Lee boolits (TL356-124TC) in .357 mag cases with 12-13 grains of 2400. When they go, they shoot great, but I have had a huge number of squibs, powder doesn't burn, boolit lodged in the barrel, PIA.Thought it was the crimp, so I tightened that up–a few less squibs, but still too many. Can't be the powder (can it?). New, uncontaminated container. Besides, some go boom very nicely. Also a few hangfires (1/2 second or so). I'm gonna try some CCI mag. primers and an even stronger crimp and see what happens. Ideas?

[ku4hx]

I've always gotten some unburned powder when using 2400 but MV is surprising consistent. But for 2400, I limit boolits to the heavier ones for the particular cartridge and don't down-load. In .357 that's 155-160 grain cast boolits generally.

My records show I've used Alliant's top load suggestion of 17.5 2400 and gotten good success with a 125 JHP. If you want to continue to use 2400 I'd suggest a heftier 2400 charge is called for. But if you're wanting a gallery load, a faster burning powder seems to be indicated. I like Unique but that's a personal choice.

And, only because I've got so many empties, my reduced power loads in .357 Magnum are actually 38 Specials. Again, I favor 155-158 grain cast and 4.3 Unique clocks a hair over 900 fps.

[sqlbullet]

More powder or a faster powder. 2400 doesn't like to burn below its.pressure range. Like max loads you can't go below starting loads and expect optimum results except with specific powders.

[Boolseye]

Yeah, I did notice much better results when I got up around 13.5 grains. Thanks folks.
So, could it be the primers as well? I've never had an issue with Fiocchis before.

[snuffy]

Have been loading some 124 grain Lee boolits (TL356-124TC) in .357 mag cases with 12-13 grains of 2400.

Wrong boolit, wrong powder. You're shooting a 9mm boolit in a 357 magnum? That's about as bad a combination I can think of. Unless it cast way oversized, and is sized to at LEAST .358, you're pushing a smaller diameter than you should be with a slow burning powder. Never mind what type or make of primer you're using, it's the load, not the primer. Heavy crimping a small-for-bore-boolit won't make it work right.

Get a proper .357 boolit mold, sized appropriately, and use a faster powder. I saw someone here saying the 358-105-SWC lee boolit works great in 9mm AND .357, so I ordered and just received a 6 cav. Gotta heat up some lead later tonight.

[williamwaco]

Have been loading some 124 grain Lee boolits (TL356-124TC) in .357 mag cases with 12-13 grains of 2400. Ideas?


I have had very good results with that bullet in the .38 special and the .357 Mag.

I used much faster powders. Slightly under max loads of Bullseye or Unique produced 1.5 to 2 inch groups at 50 yards from a 12" Thompson Contender.

I don't think it is the primers. I think it was the primer that pushed the bullet into the barrel.

I think the problem is a combination of a bad match between bullet weight, powder burning rate, and charge weight.




.

[btroj]

How much bullet pull did you have? How firm a crimp? If you don't have strong crimp AND bullet pull you don't retard bullet movement early on and pressure doesn't build like it needs to for a good burn. Mag primers are not likely to help. Been down this road before.
And it is bullet pull and crimp, a strong crimp alone doesn't always do it.

Or as others have said, use a more suitable powder. This is a place where Unique or AA5 would be right at home. May not get quite as much velocity but they will always go bang.

[Larry Gibson]

Not enough bullet mass for consistent ignition with 2400 in a 357. As stated; "wrong bullet of the powder or wrong powder for the bullet". Either way the combination is wrong. Even with a 150 gr cast bullet 2400 will not begin to burn efficiently until serious .357 magnum psi's are reached.

Larry Gibson

[44man]

I can't add a thing to the knowledge presented.

[Boolseye]

Alright, I appreciate al the input. Thank you all.

You're shooting a 9mm boolit in a 357 magnum? That's about as bad a combination I can think of. Unless it cast way oversized, and is sized to at LEAST .358
The boolits drop out of the mold at .358. I don't size them. It's actually really accurate, so I think I'll keep working with it in the .357/.38. Its big enough for the bore of my S&W–more accurate than in my SIG, actually. My next mold is that 105 grain semiwadcutter you mentioned, though. Looks like a great boolit. Have fun casting 'em up!

I do appreciate the insight into the 2400 choice, though. As always, I welcome the knowledge of those who have been at this a whole lot longer than me!

[Boolseye]

switched over to Unique or faster powders. problem solved.