Another thing, what diameter would you recommend to Dynamic .25 (as good i know with STX Slug liner) from ATP Queen? Or have you tryied that liner with your ammo? What would be your recommendation to get best accuracy. I have heard the ATP Smooth is not performing in that rifle as well as the Queen.
Unfortunately, there is no magic formula or rule. The only reasonable thing is to perform a proper test (the procedure described above) with more types of slugs or dimensions.
ATP Queen with 2 pcs of FX barrel worked better for me in size 6.36mm, that's why we have them written like this, but considering that LW produces their barrel with a specified tolerance of +- 0.02mm, I have no illusions that those tolerances won't exist with FX.
So it is always better to order both packages and test which size works correctly if you want to look for absolute accuracy.
For example, both ATP King 5.52mm and 5.50mm worked well for me in the FX barrel in .22. The 5.50mm is probably a bit better. But if you have an FX barrel where the tolerance is on the upper dimension, then the 5.50mm can also fly out without a twist and will whistle and be extremely inaccurate.
The most accurate slug is one that is exactly 0.01mm larger than what is needed to properly hold in the grooves. The problem is that this is right in the middle of stability, so the certainty is better to be 0.02-0.03mm from this limit, when the difference between the ideal ones can really only be recognized by a very experienced shooter during many tests
Do you have any videos showing your small CNC machines churning out slugs? It would be interesting to see your process. I would understand if you don't want to show -- proprietary information, etc.
Considering how other manufacturers copy ideas that we don't have patented, I will do everything to ensure that such a video never appears publicly, or better, that it never by made.
5 years of development and hundreds or smaller thousands of hours of gradual fine-tuning to be where we are now and to be able to offer an affordable variant of CNC slugs with maximum quality.
If anyone thinks that our slugs are expensive, then the only one to compare them to is these CNC bullets for .22LR. And they make them with regular CNC technology, not with a special machine, because you can't go to companies that make CNC machines and say " I want one CNC for turing lead with an ideal accuracy of +- 2 microns "
https://cuttingedgebullets.com/curx-42gr-22lr-bundle-200ct (price 111 USD for 200 pcs)