Sizing after PC...is it a must?

[Bnt55]

After reading through the powder coating procedures, I decided to PC a few 9mm boolits for grins and giggles. After a couple of tries and a small powder coat explosion (make sure the lid is on tight when shaking) I now have a bunch of boolits that are powder coated and no sizer, oops. Is sizing a necessary step after PCing, can I just make up a dummy without sizing and see if it chambers?

[Walks]

Yes it is a MUST DO !!!!

I recently made the mistake trying to load some .44cal 250's after Powder Coat without sizing. They "miked" at .435, a bit too big for case mouth flare. And My taper crimp die was way too small to get them more then a 1/4" into the die.

So Yea, sizing after PC can be mandatory in most cases.

[TjB101]

Same here … checked a pre-sized 44 coated pill and they were at .432 to .435

[PopcornSutton]

I size before and after PC.

[FLINTNFIRE]

I do not size after coating , it really depends on what size your mold and alloy are casting , some of mine were less then large as cut , others were custom ordered for size , chambers and seating depth play a part , how thick your coating is plays a part .

So No it is not mandatory , it may be needed for a individual firearm it may not .

Make up the dummy and try it .

[bangerjim]

I also size BEFORE and AFTER PC. Only ONE coat of powder with ESPC process.

Works great. Perfect boolits every time.

But it depends on your mold and your barrel size, so there is not set rule. Do what you need to do.

[jcren]

Don't forget Lee and some others make inexpensive push through dies to fit standard presses that work perfectly for pc'd bullets.

[Pablo 5959]

I size for every caliber but my Marlin 357 micro-groove. It went from 20% not even hitting paper at 50yd, sizing at 358. To 1 1/2” groups at 50yd not sizing.
In general after coating they come in at 360- 361.

[DougGuy]

After reading through the powder coating procedures, I decided to PC a few 9mm boolits for grins and giggles.

What gun?

[gpidaho]

I size before and after PC. Me too. After powder coating your bullets will vary in size by a small amount and at times will cause chambering problems. Gp

[405grain]

I usually size both before and after powder coating, and I usually seat the gas checks when I size the first time before coating. There is one exception though: When I want .312" boolits I size my 30 caliber cast bullets to .309", then powder coat. I don't size these after the PC and they come out just right.

[Bnt55]

What gun?

Going to try them in my Ruger SR9C and a Taurus G2 Millenium. I'm guess I had better run them through a sizer, they are about .002 over after PC

[Budzilla 19]

Before PC, I size and install gas checks, if needed. After PC, I definitely size to have a consistent size of all boolits.

[Charlie Horse]

I size for every caliber but my Marlin 357 micro-groove. It went from 20% not even hitting paper at 50yd, sizing at 358. To 1 1/2” groups at 50yd not sizing.
In general after coating they come in at 360- 361.

I must try this experiment with my Rossi.

[DougGuy]

Going to try them in my Ruger SR9C and a Taurus G2 Millenium. I'm guess I had better run them through a sizer, they are about .002 over after PC

Factory barrels are hard enough to get cast loads to feed right, if the barrel hasn't much freebore in the throat, even harder when PC compounds the issues.

[FLINTNFIRE]

Try a dummy round and see , I powder coat all my bullets except for black powder , consistent is the key , for a few firearms I have had custom molds with my specifications for size , I have other molds that cast small enough that coating has not been a issue .

Have let a friend load for his xdm it required a little deeper seating then my 1911 did , same with a pair of cz75 , my 38 specials are shot out of 357 magnums and same bullets loaded in 357 fit just fine , your gun will tell you what it will feed or shoot best with .

I have found tighter chambers in my rifles then in my pistols , but only shoot cast in certain rifles as others get jacketed , some of the AR calibers need sized to chamber cast bullet loads , all the 45 colt rifles and single actions shoot as powder coated cast fine , but the 50-95 needs sized if I was shooting coated , now a 40 s&w will not feed round nose but feeds a wide flat nose just fine same length of seating and all there is no for sure on what will fit or feed till it is tried .

[charlie b]

My 9mm (HK) hates PC. There is no throat. The 'edges' of the 'rifling' just shave off the PC and then you have plain lead going through the tube.

[popper]

9mm barrels are all over the place in dimensions and quality. So it depends. If you start with a 357 sizer it can be honed out to what your gun needs. Or get the NOE in several dia. You also need a case expander die for cast.

[tankgunner59]

I intentionally loaded some PC'd dummy rounds without sizing them to do a drop test. Sum up my results just by saying, size after powder coating. Each one got stuck to some extent and it wasn't fun. Before that I always powder coated and I haven't quit.

[AndyC]

Generally, yes - but slug your bore first and then measure the diameter of your PC'd boolits; if they're only a thou' or so oversized versus the bore, you're good. If not, then size 'em.

[fredj338]

I size all my bullets regardless of caliber but especially in 9mm. There are so many variables in brass & final bullet size that sizing just saves headaches in reloading. I bought a Lee APP for bullet sizing, very fast & cheap.

[DougGuy]

Generally, yes - but slug your bore first and then measure the diameter of your PC'd boolits; if they're only a thou' or so oversized versus the bore, you're good. If not, then size 'em.

Size to fit the throat not the bore.

I don't know that a lot of factory barrels will even chamber a round .001" to .002" greater than groove diameter of the barrel, -without- being throated first.

[justindad]

Does anyone cast boolits for PC that are slightly undersized relative to lube style boolits?
*
I’m thinking about getting a mold from Accurate, sized to groove diameter, and then letting the PC bring the final result up 0.002” over groove dia.

[charlie b]

Yes. When I ordered my molds from Accurate I take into account the PC thickness and spec them accordingly.

Just remember that if it says +/- .002 then whatever the minimum is should still be OK with you.

Sent from my SM-P580 using Tapatalk

[gunnie]

Depends on what size the mould throws & desired end size.
I will size before & after coating to ensure the correct size. Others will only be before coating & for one (38S&W in a Webley) only after coating.

[AndyC]

Size to fit the throat not the bore.

I don't know that a lot of factory barrels will even chamber a round .001" to .002" greater than groove diameter of the barrel, -without- being throated first.
That's more technically accurate - good catch, but I still want to know the bore size.

[Dragonheart]

Maybe a better question is do you buy bullets for a 38 Special to load in your 9mm? Do you buy.303 bullets to load your 30/06? Why not, because it is the same reasoning or lack thereof.