As an FYI, recent production Remington 40X rifles use a 14 twist.

From Lilja Barrels FAQ page;

Q. Rimfire Barrels: 16 or 17 Twist, which is best?

A. Our answer is; we don't know. We offer our rimfire barrels in two different twists, a 16" and a 17" twist. We've shot both and can honestly say that we can't tell much difference, they both seem to shoot very well. Some of our customers seem to prefer the 17" twists and others say the 16" is best. The 16" has been the standard for rimfire barrels for a long time and they are very proven. But the 17" twist is an excellent choice for BR-50, IR50/50 and NBRSA benchrest competitions.

To further complicate the issue, we also offer both twists in two different inside diameters. Our standard dimensions are a .2215" diameter groove and a .217" diameter bore. The `tight' barrels are .2200" by .215" diameters. Again, we can't see much difference between them. We sell a lot of all four combinations and can't say that any one configuration is a runaway favorite. The 17" barrels do seem to becoming more popular all of the time though.

All four types have shot very well in the competitive rimfire sports. They have won major tournaments and set records.

tim,    do you think its a matter of consistent velocity?    just looking at twist rates alone with out factoring in real-at-the-bench velocity is only looking an one factor in a multi-factor problem  fortunately with 22 target ammo the bullet weight is pretty standardized.

QuestionableMaynard8130 wrote on Nov 6^th, 2014 at 8:03am:


It's likely several factors. First at subsonic, 17 twists are right on the edge of stability. Velocity variances can contribute, if your on the slow end to begin with, however, the better ammo I've had has been often within say 5-7 fps. The type of bore and chamber contribute. Remember, when that slug upsets in the bore you have a substantial trailing edge of a hollow base slug and slight unevenness here doesn't help. Lastly, one of the biggest issues contributing to instability and it applies to any twist,is a bore less than round. You would be amazed how many hand lapped match barrels are not round in the bore. This is where slugging and measuring comes in handy. If you get much over .00015"-.00020" out of round it will hurt you. You're now hurling oblong slugs down range. The best barrels I've ever shot are generally under a tenth.
Last but not least, it's much harder to keep them round if they're 2 or 3 groovers.