I think it was made that way by mistake.  Here is an earlier thread about it:

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I just measured the twist of a RKS .22 gain twist blank as if it were a consistent twist barrel not a gain twist. I checked it twice and it comes out 21 1/2 inches. 
The blank is a 30-16.3 gain twist. 

If JHMs 16.5 gain twist barrel was measured incorrectly, would it measure 22 inches?

26W ? My other RKS blanks are marked in inches  " not W. 

RKS would make a .22 blank with 22 inch twist? Gain twist? And then tell you it's good?

1/4 inch groups from a Hepburn? 

Can't remember exactly but the one thing I am sure of is it was marked RKS  16.5 and .222 because I stamped it underneath the forearm. There was no W or other numbers or anything else. I checked it several times and got 1 in 22 and yes I know how to properly check twist. As I said when I talked with Gerald he said he put it on an action (don't know what kind he didn't say) and shot it. Does it matter what kind of action you use? Is there a difference between a Hepburn or a bolt action? As I said he is sending me another blank and I will fit it up and go from there. Hopefully it will be better. This whole thing has been a debacle from the start.


JMH

JMH,
Yes, the action does matter!  So much of this is about lock time.  There are a lot of other variable that come in to play but the time from when you jerk the trigger until the bullet leaves the barrel is critical to small groups.  Why do you think bolt guns rule?   
A real short, quick drop of the firing pin to ignition.  Besides the ability to get everything precise and square with minimal effort.  Fitment of the action and barrel to chassis or stock all come into play.   I have more than a few high end bolt guns for 22rf.   Given even a marginal barrel, an exceptional means of holding that action (stock or chassis), good glass, good ammo and mechanical means of shooting the assembly the groups from this will run circles around a vintage slow lock time, assembled from a casting stuffed in a piece of wood that applies stresses that only a few take the time to figure out.  There are exceptions to every rule and we see more than a few of them. 
 
As I mentioned in one of my previous posts, the Hepburn is one of the actions I'm referring to.  It has a heinous hammer, lots of mass to get going, lots of energy once it gets going.  That energy gets tranferred to the block, to the action, down the barrel, etc.  You don't think this has any effect on accuracy?  Get behind this when you get it back together, shoot a round, then before you eject the fired cartridge, PULL THE HAMMER BACK AGAIN DO THE FOCUS AND SQUEEZE ANOTHER OFF.  Tell me what you see.  It moves around a lot.  The argument is it'll do that same thing everytime all you have to do is manage that... It's a variable that's tough to control.  Try that with a high end bolt gun, a Turbo, Stiller, Vudoo, 40X, Anschutz, even a Martini, not much disturbance, some of these depending on design don't move off the dot.  Given a good bench setup, even with recoil they still don't move off the dot.
GT

marlinguy wrote on Sep 6^th, 2026 at 9:03am:



Exactly. 

I made a fixture and used a degree wheel for setting cam angle.  Measured the change in every inch, plotted points in Excel and it gave me a curve of what the exit twist is.  A lot of hoopla and it's been a while ago.  There's four common types of gain twist configuations and I don't recall exactly what Ron uses but for our game works, a simple linear? 
GT

Thanks Joe.  I understand now.  So before milling mine would have said 28" at the bottom which makes sense because I ordered it to finish at 28". 

Chris.