Gas Checking a Poly-Coated Bullet

I would say your good. However I'd encourage you to switch to hitek coating. Way better and easier. Also can do gas checks because the coating is thinner than pc

The various coatings out there hold up well past the limits for anything you will push a 158gr bullet to.

If you have a GC mold it doesn't work well with the coating IME. The best mold for coating is one that isn't setup for a GC.

I've pushed them over 1300 without gas checks and had no issues.

I have some dies that make gas checks for plain base, 38 caliber bullets and have dabbled with trying them with my powder coat bullets. I make gas checks from aluminum drink cans. While I have not pushed the velocity of the loads, I have not had any other problems with the gas checked powder coated bullets.

Maybe one of these days I'll get back to playing with these gas checked, powder coated bullets.

Snowdog said:

Am I correct to presume I don't need a gas check for 158gr SWC/SWCHPs loaded on the warm side?

Click to expand...

Depends!

2 items
1. How does the bullet fit in your chamber & barrel?
2. How hard is the bullet?

Most leading IMHO is because the bullet/barrel fit is too loose.
This allows hot gases to burn around the bullet base & melt, thereby giving an awful lead mess.

Hardness can be an issue too if the bullet is too soft.
But I still think fit is a bigger issue.

Just my 2¢ worth YMMV

If you have to scrape off 3mm of coating you're doing something wrong. That's a VERY thick coating.

I took it to be that he took that much off the sides at the base so he could attach the gas check directly to the lead. I would size them with a gas check first then PC them and size again. IMHO that would be easier to do if you wanted both PC and a check. Just sayin.

Before powder coated bullets ever came along I shot plain base cast bullet using tumble lube or traditional lube in my 357 mag. loads at full velocity with no leading. Using the correct dia. bullet that fits the cylinder throats of your revolver as well as an alloy that matches the velocity and pressure level of your load is the most important thing first. PC to me is just a form of lube with a few extra benefits over traditional forms of lube, it want turn a 8 BHN bullet into a 15 BHN bullet and I always find that at some point a bullet designed to use a gas check will always shoot more accurate with the check installed than not at least in my testing.

I shoot lots of bullets that are designed to use a gas check with the check left off and I did that way before powder coating came along, but I didn't push those bullets hard as they were cast from softer alloys and mostly used for light plinker loads in handguns and rifles which are generally very accurate anyway so the check really didn't serve a purpose. I mainly only use a check with HV rifle loads or rifle and pistol loads that use a softer alloy that I want to get some expansion or deformation with that can't withstand the velocity / pressure curve without the check installed. My advice would be to try some bullets with the gas check installed an some not with an identical load and see what shoots best.

Although mainly for handguns info here is a good read on gas check vs. plain base bullets.
http://www.lasc.us/Fryxell_Book_Chapter_10_GCkorPB.htm

I should add that I've PC'ed lots of different rifle and pistol bullets an had no issues putting gas check on after powder coating as long as the bullets weren't over coated to begin with but that hasen't been an issue in a longtime.

Clear coat with copper checks, Accurate mold.


Carolina Blue with Aluminum checks, Lee mold.

Gas check then powder coat. Problem solved.

IMO, the two main reasons for PCing a bullet is to eliminate lube and gas checks. I've PCed gas check design bullets, loaded sans gas checks, no problems...