By Corey Sattler
Here is the info I have collected for .223 twist ratios from various sources (including in-house testing & ammo manf. contacts).
1x7 - technically too tight of a twist for any .224 bullet widely
available, including the 80 gr. Manufactured originally to stabilize SS109
and/or tracer ammo, but further military testing has shown other twists to
be superior. Some of the very heavy custom stuff (87 gr?) may work well,
1x8 - great twist for 69-80 gr bullets. Sierra once informed me that the
perfect twist for their 80gr was 1x8.2xxxxx (blah blah blah big long
engineers explanation followed).
1x9 - good all around twist ratio. Best suited for 52-69 gr, but either
end of the envelope will be questionable.
1x10 - practically the same as 1x9, but favors the lighter side a little more.
1x12 - great for the 40-52 gr bullets. Most often found on bolt action
rifles as their primary use is varminting. All right for the 55 gr, but
not the best.
1x14 - if you want to understabilize the .224 bullet, use this twist.
Useless except for tumbling effect it causes upon bullet impact. IMHO,
better to shoot straight with a good HP bullet as your chances to hit are
better and damage will most likely be greater also.
About the author:
Mr. Sattler is the Law Enforcement Sales Manager and
Archival Records Manager at Olympic Arms, Inc. in Olympia, WA and has
been with the company since 1993. He is also a Reserve Deputy in a
small Southwest Washington county Sheriff's Office.