Is there a built in speed limit with powder coating?

[saskgunowner101]

Just wondering what the collective experience here is with powder coated cast bullets and higher velocities. Is there a point where a PC bullet will start leading? Accuracy goes to pot? Bad voodoo stuff that I can't possibly imagine happens?

The reason I ask, is usually I shoot PC bullets at moderate speeds, probably 1,800 fps or less and absolutely love them, but have no clue what happens when you really step on the gas. I'll assume gas check designs fare better at high speeds, but what about powder coated flat or bevel base bullets without a gas check? Any thoughts, experiences or opinions appreciated.

 

[iron cat]

I am patiently waiting to hear chronograph and accuracy results myself!
I have been told they can go well past 2,000FPS, especially with harder lead alloys, but I have no first hand experience as all my higher velocity rounds were still just under 2,000 with my powder coated 9.3X72R rounds.
Cat

 

[slug]

Pre covid, I posted here about how some of my ugly blotchy bullets were shooting well.
I was getting 2440 f/s out of a .30/30 with good accuracy.

Pre turn of the century, I was getting a whisker under 3000 f/s in a .243 with greaser bullets.
It was just a few shots and things were kept very cool.. There was no leading, but the bullets went all over the map, with none touching the target.
An exercise in futility.

 

[freire]

I have pushed them to 2400fps out of a .308 Win with no leading, my best group was around 2.5" at 100 yards.

 

[PPCLI-Jim]

Are you also gas checking and pc or just PC'ing

 

[slug]

If there's a gas check shank, I use one. However, I shoot lots of bullets with plain bases.

 

[fingers284]

I use GC shanked slugs like BT's no gc and just PC. The PC takes care of the leading issue and I have seen no accuracy betterment when using GC over plain base when PCing so checks have become redundant for me.

 

[saskgunowner101]

Thanks for the thoughts, I guess I'll eventually find the speed limit, whatever that may be.

 

[boxhitch]

watching...

wondering if twist rate will have some influence on max fps and rpm possible with cast

 

[saskgunowner101]

watching...

wondering if twist rate will have some influence on max fps and rpm possible with cast

Good question!

 

[slug]

In the second edition of the Lee reloading manual, Richard Lee wrote a very interesting article regarding pressure and the strength of the bullet and it's ability to resist deformation. It's a simple concept, but I've forgotten the details over the years. I was introduced to powder coating by Old Rodder, and it became less important to me since powder coating serves me very well in the more modest loads that I use.