[SGT. Schultz]

I wonder if the modern 12 Gauge Top Gun hull with plastic base wad has more internal volume than the old ribbed Gold Medal hull?

Yes it does. That's one reason why it's safe to use FGM hull data.

 

[cloudmt.ranch]

All three loaded using Bullseye (17.5 gr) one using a CB6100, one using a Fiocchi H27 and one using a gualandi REX wad. No shot cards ,beans ,cheerios just one ounce of shot.
View attachment 19311
I could have fine tuned the crimp some. But left everything set to load Fiocchi hulls.

Very nice......
I have seen factory crimps that were not as good...

 

[cloudmt.ranch]

Here is a case cutaway

The Federal Gold Medal is on the RIGHT
Top gun CENTER
Federal HOA LEFT
The T G base wad is huge

 

[cloudmt.ranch]

Now if we could figure out what powder The Fed folks are stuffing in the T G hulls....

Here is what is in them....16.5 gr..... (This piccy is contents of a new style T G 1 OZ load )

 

[SGT. Schultz]

The powder is probably 360 from New River Energetics.
You can not get that powder. Unless you become a "commercial" loader. The closest canister grade powder (probably) would be Extralite. But even that is not an exact match.

 

[cloudmt.ranch]

Good to know this info