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XTR
11-05-2020, 03:55 PM
It's probably been asked more than once but I'm failing to find it (and I did search)

I've been casting for my BPCR for a few yrs now, but I've never bothered with my pistols, but I'm about to start for my 45s and for my 40.

Given that powder coating makes boolits bigger so they have to be sized, probably by .002 to .004 best I can tell, and my experience sizing more than about .002 is less than ideal. Would it make sense to get a mold that was .002 undersized for PC boolits?

I get that it would be a purpose built mold at that point, yea, it's not useful if you aren't coating. I understand that part. I'm not too worried about that.

.

Wheelguns 1961
11-05-2020, 04:02 PM
The amount that powder coating adds to your diameter is directly related to your technique. Personally, the way that I pc my bullets adds .001-.002 at the most. I try to buy my molds the same size as the bullets that I need or .001” over. Szing bullets also makes them more round. I would think that if you are having trouble sizing your pistol bullets, maybe your alloy is too hard.

FredBuddy
11-05-2020, 04:08 PM
Interesting question.

I'm no expert, but all my moulds are standard
off the shelf dimensions and I powder coat the
boolits from them. I have no problem sizing
them to the dimension for the finished product.

Powder coated boolits are slippery if they
are cured properly. If you are thinking about
jumping in, I recommend Smoke's clear powder
to start with. Also, read Banger Jim's posts
for all the tricks.

Go for it !!!

GARD72977
11-05-2020, 04:59 PM
The equipment you use to size them means a lot. The Lee App press with factory Lee or Noe sizers make it much easier.

Some of my old Lyman sizing dies scrap off the PC. The dies made for the Lee are heavily chamfered for higher production rates. This Is a big deal for PC bullets

XTR
11-05-2020, 05:14 PM
I haven't made pistol boolits in the past, but shoving a 405 gr smooth sided PP or a 535 gr GG for a 458 though a sizer requires that you lean on it pretty hard if you're taking much off at all.

I'll play with some factory molds and see how my coating technique does before get Accurate to make me an undersized custom, but I want to think that it may be something I do in the near future.

Thanks for the tips. I've read a bit, and watched a few vids on coating, but haven't tried it yet. My main press is a T7, but if I start doing this for production numbers I may get a Rock Chucker just for sizing.

bmortell
11-05-2020, 08:47 PM
i dont think its much concern. for example i slugged a bore at .4315 ordered a .432 mold for PC and size at .4325, and i can even size fine with 2 coats easily unless the lead is heat treated but i could do that after coating and sizing.

rockshooter
11-06-2020, 12:08 AM
I use standard size for caliber molds but am careful about the noses. I like the nose to have a little distinctive diameter decrease. Examples of that step are NOE 403--198-WFN-Y1 and NOE 358-131-RF-R5. Without this small step, the bullets have trouble with the throats after sizing in some pistols, but not all. My Beretta M9 eats anything, the CZ 75 not so much. A small tip on resizing: spritz the coated but unsized bullets with a little Hornady One-Shot before sizing- makes life much easier.
Loren

Cosmic_Charlie
11-12-2020, 05:26 PM
Just ordered a mold and asked for .431 boolits. That diameter will work tumbled lubed for my SBH. But I really wanted it for my 24-3 Smith that needs a .432 boolit. Since I powder coat that diameter will work well for it.

Conditor22
11-12-2020, 05:43 PM
XTR
How hard are you casting the boolits for 45/70?

you can use a little case lube (lanolin/alcohol) on the boolits helps sizing go slicker

My 45/70 like 459.

try knocking ALL the excess PC off the boolits before you bake them. IF you leave a lot of excess PC on (the color looks great that way) you can add .003-.005 to the boolit diameter. what do the boolits measure before and after PCing?
IF you use an alloy harder than is specked for the mold the boolit will drop larger.


Sizing down .004 is easily doable unless the alloy is super hard, the sizing die is rough on the inside.

try polishing the inside and entrance of the die lightly with 1200 grit wet/dry.

cwlongshot
11-12-2020, 05:55 PM
I routeenly size down .458 designed bullets to .454 and .452 for use in my 450 Bushmaster.


NEVER EVER has the PC "scraped off". It merely gets nice and shiny.

The key is PROPERLY APPLIED AND CURED application of the PC.

CW