Thread: "Air space" in 303 British and 308 Winchester caseloads...Dangerous?

Originally Posted by Pommy

Don't use fillers.

1. Give a factory round a shake and listen to the powder rattle around. A 100% full case is ideal for consistent ignition and chasing very low extreme spreads, but it's perfectly normal to have less than 100% and a little airspace.

2. One full bullet diameter is a good guideline. Some go less, 2/3rds or even 1/2. But more will aid in concentricity and give increased tension which is kind of what you're after with hunting ammo.

3. The boat tail isn't measured in the above, so for a boat tail bullet the guideline above would read "seat the entire boat tail plus a full bullet diameter".

Gotta be quick with answers around here!

Yup Pommy summed it up in a nutshell, concentric rounds are more important than jump in my book. But that's just me.