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I have tried several methods to prevent case stretching in resizing botlle neck cartridges
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How do you know you have excessive case stretching? Have you experienced some case head separations?
Case stretching is caused by setting the shoulder back more than required to chamber properly in your rifle.
By their design, normal FL sizing dies, undersize the neck so the expander can enlarge it for proper neck tension when you seat the bullet. You can use a die like the Redding S die and by using the proper size bushing, you may not have to use an expander and still have the correct neck ID for your brass/bullet.
You can reduce the "force" required to withdraw the expander by either lubing the inside of the neck, using a carbide expander, or both.
But you haven't addressed neck runout. And your process may increased the run out of the neck and decreasing your accuracy.