Lee Precision Resizing and Decapping Dies have a built in feature to save you from breaking decapping pins.
 
The decapping pin is retained by a collet in the die. This decapper clamp can be set to ensure that if you run into one of those damn Berdan primed cases your pin will only be pushed up with no damage to the pin.
 
To set this grab a size 19 spanner and a size 13 ring spanner.  Gedore spanners work nice as these nuts are all imperial sized. With the die in your press, take your 19 and hold the die body. Use the 13 ring spanner on the decapper clamp. Now set the pin flush and tighten just enough so that it will deprime a boxer primed case.
 
Now test a Berdan primed case and make sure the clamp is not too tight and that the case actually moves the pin up.  This will be a case of trial and error but you will find that sweet spot.
 
This will save your decapping pin.
 
There are 2 more methods to save your decapping pin.
•   Inspect your cases. Yes this is tedious but will save you money and time in the long run. Mark your cases to identify them easily on the range. If you do pick up a case without your marking, inspect it first before processing.

•   Do not force your press! If something does not feel right, rather look and find the problem...and yes even old hands get caught with this.  So again...Do not force your press!
 
 
And it's just not Berdan primed cases that can break decapping pins. Crimped primers can also be a problem...S&B has cases marked NX, these have crimped in primers and a smaller flash hole.
 
They can be processed but you need to be willing to offer up a decapping pin or 2.
 
I usually just dump these in the recycling bin but I have recently found a few in my cases and decided to process them.
 
I use a rifle or universal decapping pin for this job. I over tighten the decapper clamp so that it does not allow the pin to move. At the moment I am using a 5.7x28 pin and it has not broken yet.

These crimped primer cases also need to have their primer pockets swaged. This will allow for easier seating of a new primer. The Lee Automatic Processing Press has been a blessing for this...its Primer Pocket Swager Kit works a treat.
 
You need to decide if these S&B NX cases are worth processing.
 
And also remember that a pin will break eventually, with enough use the pin will become brittle and break.
 
Even with all these tips it is always best to have spares on hand. I have learned over the years that things tend to break at the worst of times so having spares on hand might just save your reloading session.

Yes, have a spare or TWO ! on hand, I have found that when I break a pin, there is usual Murphy's brother Berdin case in batch - just one more to break your spare. So have a spare spare, its not like it can go off or has a use by date.
Also nice to have a spare spare for that mate who is not as prepared as you.
Hero for a day scenario.

Just make sure to oil it inside the little bag. Using a rusty spare does not do your cases any favours.