300 win mag S bushing and mandrel brass issue

[BirdDog50]

Having an issue with S bushing followed by mandrel sizing of the brass. It's a 300 win mag Redding S due & 21 Century mandrel die. It's Noslser fired brass. In the past I've had success with the S bushing .332 or .333 and the..3055 or .3070 mandrel. For some reason I get mixed results... A simple test I do is to take the case and insert the bullet to see if it's tight and about 40% of the cases the bullet just slides in the whole way with no resistance. I can't figure out what step I should take to get a better consistent result. Any advice would be appreciated. Hopefully I've given enough detail. Thanks

 

[BirdDog50]

I forgot to add I recently purchased a additional S bushing .335 and still have mixed results.

 

[WeiserBucks]

How many firings on the brass?

 

[OrionsStar]

Did you anneal the brass prior?
Maybe an over annealing issue? I unfortunately experienced this on a flame annealer. Ruined the entire batch as it lost it's elasticity. Completely my fault, never good rushing the process.

 

[sable tireur]

Since we don't have any real information to go by, I will make a suggestion for you to try.

Nosler brass may be expensive but that doesn't mean it's high quality. Factually, it's expensive and fairly low quality no matter what the supporters (influencers) want you to believe.

Take some time and sit down with a tube mike or calipers if you have to, and measure the neck thickness at 3 or 4 points on the neck. You may be surprised at the inconsistencies in the brass neck thickness.

It has been noted that the annealing can be inconsistent as well.

Try some good brass to see if it makes a difference.