Need hep with sizing Dies.

[glowe]

Hello everyone.

I slugged my 2 pistols last night. The wood dowel broke in my 7' .357. That was fun trying to get that out, anyways.

Info.

--S&W, 686+ 7". slug measured .355
This was hard to measure, with 5 rifling in the barrel, I can't get a true measurement.

--IWI Jericho 9mm. Slug measured .353

I was thinking that I could get way with only one sizing die for both.

There will be a beautiful Magma Star Lube-sizer at my house in 4 weeks.

What do you guys think? What sizing die would be the best. At $50 a pop I would like to get it right the first time.

Thanks

Greg

[captaint]

IF there was one size - I would try .358. Not everyone will agree. That .353 groove diameter for the 9mm sounds small. Are you measuring with micrometers ?? They are the best - always for slugs. You should measure your cylinder throats in the revolver. Cylinder throat diameter is most important in a revolver. My .02. enjoy Mike

[glowe]

IF there was one size - I would try .358. Not everyone will agree. That .353 groove diameter for the 9mm sounds small. Are you measuring with micrometers ?? They are the best - always for slugs. You should measure your cylinder throats in the revolver. Cylinder throat diameter is most important in a revolver. My .02. enjoy Mike

I'm used a good quality caliper to measure it. I measured about 10 times from different spots to get the over all size.
I have a micrometer, so I'll re-slug and measure.
For the Cylinder, Do I slug each one?

[runfiverun]

i'd just try the 358 first.
then look closer if there is an issue.

[williamwaco]

You are measuring the wrong diameter.
You are measuring the bore diameter instead of the groove diameter.
The high spots on the slug correspond to the grooves in the bore.

See:

http://www.google.com/imgres?hl=en&sa=X&tbo=d&biw=1321&bih=665&tbm=isch&tbnid=NuERhAScsemTEM:&imgrefurl=http://firearmshistory.blogspot.com/2010/05/rifling-terminology.html&docid=1e_GtwrCRglekM&imgurl=http://3.bp.blogspot.com/_59GYpEVAu0U/S_NyVDPVw7I/AAAAAAAAAFI/bnE9unBLDZw/s1600/boredia.jpg&w=429&h=419&ei=iij3UKOZLfLU2QXLvoC4Ag&zoom=1&iact=hc&vpx=518&vpy=122&dur=610&hovh=144&hovw=148&tx=114&ty=111&sig=107900492181417674669&page=1&tbnh=141&tbnw=145&start=0&ndsp=28&ved=1t:429,r:3,s:0,i:94


Note that the the high and low spots on the slug are reversed from the barrel bore.

You are right. Measuring a 5 grove bore is difficult. There are several threads here about doing it.

Now:

I never slug bores. But then, I have only been loading for about 60 years. Maybe I will get around to it next year. If you get a .358 die, you will be fine.



.

[Old Caster]

Williamwaco said it exactly right. Measuring a bore is very difficult to get right. I just try .358 and if that doesn't work (it has every time so far) I would try .357. I have only reloaded 56 years so I defer to WW's 4 more years. My first loads were shotgun with Lee Loader.