Questions about my 357 load please take a look

[milsurpaddict]

This is my first loading of 357 magnum. Looking at the case it appears that the Lee tumble lube lines are seen from the outside of the case like the boolit is to big. However when I measure this boolit it measure 3578 and the weight is right at 158. The round fits in my cylinder but I want to make sure this is not to big of a boolit.

5538355384

[btroj]

That is a good thing. Good neck tension. That is more important than crimp in getting good, consistent ignition.
It looks awful short. Could the bullet be seated out more and still fit the cylinder?

[wv109323]

No the bullet is not too big for the nominal diameter of the .357 Magnum. The Boolit should actually .358.
Where you may run into a problem is that the neck sizer is sizing the case neck too small. Most reloading neck sizing dies size for a jacketed bullet of .357. There is a possibility that seating a .3578 bullet in a .357 (or less) neck may "size the bullet" to something less than desirable.
The test of course is in group size. If they shoot well you have no problem.

[JLDickmon]

looks OK to me..
like WV said, you may want to mic the expander ball, but only if they group like garbage..
in which case, I would pull a bullet or two and mic them as well, to make sure the neck tension isn't sizing them down even further..

[swheeler]

This is my first loading of 357 magnum. Looking at the case it appears that the Lee tumble lube lines are seen from the outside of the case like the boolit is to big. However when I measure this boolit it measure 3578 and the weight is right at 158. The round fits in my cylinder but I want to make sure this is not to big of a boolit.

5538355384

I think you answered your own question.

[uscra112]

Never knew that there were neck sizing dies for straight wall cases. [smilie=s:

Do look to your expander die. For boolits, the expanded case should be at most a finger-tight fit to the boolit. If you are having to press the boolit home, it is too tight. Pull one or two of your boolits after seating it, but before crimping, and mike it. If it's gotten smaller, your expander needs to be larger.

Just to complicate matters, I've found that I have to have different expanders for different makes of brass. Some are thinner/softer and expand easily, others that are thicker/harder have enough springback that they need a bigger expander. For target ammunition, I've just started using a plug gage to check every expanded case before I prime, to eliminate outliers. The results are interesting.

BTW I have often gotten excellent results by seating a SWC boolit that deep, rather than in the crimping groove. But be warned that deep seating will very quickly raise pressure, so the powder charge always has to be reduced.

Boolit must be at least as big as your chamber throats, and better if it's .001 bigger. Measuring chamber throats can be done by driving a lead slug through them and miking it, but the best way is to buy a few precision gage pins

[saint_iverson]

Looks good, but I would like to second btroj - the boolit does appear to be seated low. Generally not a problem though if the powder is not being compressed.

I know that I use 2400 and that stuff takes alot of volume, seating the boolit too low and compressing the charge can lead to problems. Some powders can handle the compression just fine, others not so much.

I have not used the TL358 however... Regardless, it looks nice!