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Message: <blockquote data-quote="Jcann" data-source="post: 3169962" data-attributes="member: 33119">I don’t believe anyone is focusing on RPM and no one is asking anyone to take 5 steps back. An 8 twist barrel (which his probably is) will stabilize 140 grain bullets just fine in a Creedmoor.  The question of stability was asked without a clear meaning or understanding by a different poster.Your comment, “All a shooter needs to be concerned with while selecting a bullet is the twist rate of his barrel” may be true for the most part but it’s not necessarily true for the long range shooter. Say a company comes out with a new bullet with extremely high BC but needs an 8 twist to fully stabilize it and your barrel has an 8.7 twist. Can you shoot this bullet and fully stabilize it while taking full advantage of its BC? You can if you shoot it fast enough. How fast? If you use a calculator you can determine a starting point or baseline.How does the typical handloader know what twist will stabilize a bullet? You are correct in saying it’s from the manufacturer’s web site or reloading manuals. When Berger first came out with their 195gr 7mm EOL Elite Hunter it had a stated twist of 8. They have since changed it to a 9 twist but through conversations with Berger’s technical staff through emails they said it is not fully stabilized in a 9 twist barrel for all 7mm chamberings.  The only reason I see to this change was because most factory 7mm barrels are 1:9 twist. Those of us who may want to use this bullet to its fullest potential know we need a 1:8/1:8.5 twist. Also, if you are shooting a 7wsm with a 1:8.5 twist you may not get the muzzle velocity to take full advantage of the high BC unless you have a lot of free bore allowing you to seat the bullets long for more case capacity for powder. Doing this may exceed magazine length causing it to become a single shot. Now I could go out and spend $50 on a box of bullets and give them a try but I choose not to based on information gleaned from the manufacturer and knowledge in the relationship between bullet weight, twist, and muzzle velocity with regards to BC. Bergers twist rate calculator also gives the shooter a starting point for adjusted BC if twist and MV do not achieve manufacturer stated BC. Granted, these are usually tweaked based on field data, but it is a starting point. Kind of like your comment, “manufacturers have already given you baseline for their testing of that bullet/powder/primer combination”.If you shoot extended long range, how well does a bullet transition through transonic flight? They are not all equal in this regard and manufactures such as Sierra, Hornady, and Berger have test data that proves this.Will this information help cowcatcher in his reloading pursuit with the creed? No, but it may aid him in future endeavors. Keeping his reloading simple, choosing the correct bullet, powder, primer, case prep, and changing one thing at a time while gathering data will help the most. Personally I believe with the proven track record of H4350 in short action 6.5mm that’s the powder he should be trying first but I understand the issues of finding it. Your suggestion of ladder testing is a great idea if he understands what that is and how to do it. Maybe in your next post you can be a mentor by explaining this bringing value to the discussion and stop complaining about computers, calculators and teenagers who are clueless of typewriters.  I’m sure this forum was set up for like minded people to ask question and share information to those who enjoy the shooting sports and those who are trying to broaden their knowledge.</blockquote>

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