Should i size?

[Three-Fifty-Seven]

Howdy!

I just got my RCBS 38-148 WCDE heated up this afternoon . . . and I have a couple of surprises!

1. They are coming out at .3607 diameter . . . my barrel is .3562 and another at .3571, I've heard to size .001 - .003 over bore, but could I go .0045 over? I noticed after I was all done, that I had a tiny bit of crud holding the mold open so they are slightly out of round = .3607 X .3613, I've been running others measuring .3584 - .3591's through them un-sized . . . my cylinders throats are .359 think I need to invest in a sizer?

2. They are weighing in the 153gr area . . . is this normal to be over size using wheel weights?

I have only used Lee molds before today, and did not need to size . . . however, I really like using the RCBS mold, seems more like a tool . . . I went and picked up the Lee afterwards, and it seemed flimsy and a toy, I like the boolits it casts, but probably won't be buying anymore.

[lwknight]

Is it possible that your larger measurements are taken on the parting lines? That will show larger.
I would size them if for no other reason than to have uniform boolits.
I had a problem with lead building up in my cylinder mouth from oversized boolits. After checking I found that 357 would pass with strong thumb pressure and my barrel slugged at 356. So I sized everything to 357 and more build up in the cylinder and accuracy is still as good as ever, if not better.

As for the few grains light. Its normal. The molds are rated at a certain alloy and since most of us use what we can get that works, at lowest cost , deviation is to be expected.
You can read up on the manufacturer specs and see what alloy they used to rate/design the mold.

[Three-Fifty-Seven]

The larger measurement was oposite the seam line . . .

These are rated as a 148 gr boolit, surprised they came out 5 over . . . my lee is rated at 158gr and come out 156 . . . I aknowledge that they are a tad "fat" because of my error, but didn't figure that .0007" out of round would cause that much "extra" in it . . .

[Edubya]

I've got one suggestion; load one round then with your impact puller take it down, measure the resulting slug.
EW

[mooman76]

That's allot over sized. I would size it down some.

[Three-Fifty-Seven]

I've got one suggestion; load one round then with your impact puller take it down, measure the resulting slug.
EW

So your saying by doing this, to see what size it ends up after craming it into a case?

[Echo]

See if they will chamber in your guns. And what is the diameter of the chamber neck? Important...

[Three-Fifty-Seven]

See if they will chamber in your guns. And what is the diameter of the chamber neck? Important...

I think what you are calling the "neck" is what I called the "throat" ie:the forward section of the cylinder which is the last part of the cylinder that the boolit travels through just before approaching the forcing cone?

That is .359 . . . well one is .360 by accident, but still too small for it to drop all the way through.

[smilie=s:

[243winxb]

Size your bullets to .358" and then practice , practice, practice.

[Three-Fifty-Seven]

I think I got most of my leading problems solved in my SP101, still a tiny bit, but switching to BlueDot helped a lot, and varing powder amounts did wonders, after I fire lapped . . . all using 156 gr swc at .3584" now comes the fun part of of shooting for practice, all that testing is quite boring other than the wide variable results experienced with changing from 38 spl cases to 357's and different powders . . .

I just got handles for the Rcbs (Lee 6'ers) and wanted to shoot wc's at paper!