22LR twist rate

I'll discuss a portion of it openly here, but there are parts of it I won't talk about just yet. I'm not trying to hide anything or keep useful info all to myself, as it will be made public at some point soon. But, posts like this have to be managed closely and my time to be available for the coming weeks will be sporadic.
After more than three months, is there any data available yet about the performance of the faster twist barrels compared to the standard 1:16 barrels?
 
Last edited:
Yes. He explained it earlier. Longer barrels benefit from tighter twist, I think the magic number was over 24" (?)

The benefit is at 100m and beyond, sub 70m will show almost no result change, so 50y paper punching won't reveal benefits.

@RAVAGE88 can correct me on this.
 
Yes. He explained it earlier. Longer barrels benefit from tighter twist, I think the magic number was over 24" (?)

The benefit is at 100m and beyond, sub 70m will show almost no result change, so 50y paper punching won't reveal benefits.

@RAVAGE88 can correct me on this.
22"?

But I too would like some numbers.
Like, drop values (dope)
Accuracy measurements (6x5), long range

The whole thing, I would like to..learn something concrete about it, wrap my head around it.

Not pushing on anyone or demanding, just a polite inqury, if there is data from anyone.
 
  • Like
Reactions: Drew M and drglock
Yes. He explained it earlier. Longer barrels benefit from tighter twist, I think the magic number was over 24" (?)

The benefit is at 100m and beyond, sub 70m will show almost no result change, so 50y paper punching won't reveal benefits.
What would add tremendously to what's been explained about the question is direct evidence, data such as target information.

Shooters considering faster twist barrels may like to see the "benefit" they are said to have over standard twist barrels.
 
  • Like
Reactions: jego and Gleedus
Then shooters should buy one to try or just stick with whatever everyone’s been using for the past 100 years. I don’t think Mike needs to prove anything to anyone. Believe him or don’t. He won’t sell more Vudoos either way.
Buy a barrel and test for yourself. You might find some fun it it actually.
Was about to say the same.
He has no issue with order book except that he is running out of pages.

He does not have to sell anyone anything.

But what I am hoping is to some user here to gather some data. I have no intention yet to upgrade, but really would like to get my hands on any data.
 
  • Like
Reactions: Drew M and Geno C.
Was about to say the same.
He has no issue with order book except that he is running out of pages.

He does not have to sell anyone anything.

But what I am hoping is to some user here to gather some data. I have no intention yet to upgrade, but really would like to get my hands on any data.
F9036470-03B8-466E-BABB-4324359E0908.jpeg
I have data
 
What Geno said! Also what is considered a benefit will/ can be different for each of us. The faster twist will reduce velocity so will a longer barrel. So the combination may create a scenario where a higher BC is used to true the drop data and give a perceived advantage.
The only extensive test I know regarding this where I know the tester personally found 1-9 to significantly increase the amount a flier was out of the group. This was done with long barrels 26" barrels where progressively cut shorter.
1-12 faired the best. Also his conclusion was that 20-22" was optimal barrel length for accuracy. (No tuner)
Now I also have a 1-16 26" that shoots half decent that as weather allows I am collecting group data and velocity and will be cutting. I also have a 1-12 coming for testing. Once done we can compare notes and see if my results echo what his conclusion was. Once done I will share but it will be some time as I wish to be thorough and have lots on the go.
All of this was done with regular 22lr ammo and long range is the focus. 100-400 yards.
 
What Geno said! Also what is considered a benefit will/ can be different for each of us. The faster twist will reduce velocity so will a longer barrel. So the combination may create a scenario where a higher BC is used to true the drop data and give a perceived advantage.
The only extensive test I know regarding this where I know the tester personally found 1-9 to significantly increase the amount a flier was out of the group. This was done with long barrels 26" barrels where progressively cut shorter.
1-12 faired the best. Also his conclusion was that 20-22" was optimal barrel length for accuracy. (No tuner)
Now I also have a 1-16 26" that shoots half decent that as weather allows I am collecting group data and velocity and will be cutting. I also have a 1-12 coming for testing. Once done we can compare notes and see if my results echo what his conclusion was. Once done I will share but it will be some time as I wish to be thorough and have lots on the go.
All of this was done with regular 22lr ammo and long range is the focus. 100-400 yards.
I can save you going too far with the cutting. That’s basically the test I’m running now
 
I can save you going too far with the cutting. That’s basically the test I’m running now
I'm very interested in your results when your done particularly regarding velocity spreads. His testing was focused on group size and velocity lost not SD etc.
I shoot rimfire prs so 22" will be the shortest of interest to me for good balance.
 
Some good info there. Velocities are much closer in this test from 20-26 than what the internet would leave you to believe.
Only if you look at the numbers the people say not the data people actually collected. Also most people quote how 16" is optimal length. If we look at a 10-22 bolt opens approximately at 16" so at that point the pressure behind the bullet is less then bullet friction. But in a bolt gun at aprox 26" the gas pressure behind the bullet and friction are equal. There are many variables to consider such as temp that change the velocity drop with barrel length but its not like the internet would say often.
When comparing rifle to rifle you have bore dimension, head space, chamber affects not to mention ammo lot# differences but when you find a guy who cut a barrel down....
There is a tiny bit of data out there on 24" barrels that were cut down.
 
What Geno said! Also what is considered a benefit will/ can be different for each of us. The faster twist will reduce velocity so will a longer barrel. So the combination may create a scenario where a higher BC is used to true the drop data and give a perceived advantage.
The only extensive test I know regarding this where I know the tester personally found 1-9 to significantly increase the amount a flier was out of the group. This was done with long barrels 26" barrels where progressively cut shorter.
1-12 faired the best. Also his conclusion was that 20-22" was optimal barrel length for accuracy. (No tuner)
Now I also have a 1-16 26" that shoots half decent that as weather allows I am collecting group data and velocity and will be cutting. I also have a 1-12 coming for testing. Once done we can compare notes and see if my results echo what his conclusion was. Once done I will share but it will be some time as I wish to be thorough and have lots on the go.
All of this was done with regular 22lr ammo and long range is the focus. 100-400 yards.
I have to agree with your flyer statement CRPS I have viewed the same effects at higher twist rates. I must consider also if my spin drift has increased 7.38 inches at 600yds any defects would also be magnified. I have barrels piled up in the corner of my shop from 7.5 to 16 buttoned,cut, poly ratchet 2,3,4,5,6,9 groove you name it. Mr. Bush is correct in his statement on his findings , but that's for the internal profile he's using. One has to look at a broader spectrum though. That's the transition from internal to external ballistics, the stability and consistency of the projectiles transition from guided to self guided flight. Shilen solved some of this with the Ratchet rifling , it creates a larger bearing surface imparting stability to the projectile driving surface during rapid acceleration. The polygon is in likeness but not single sided , transitional or progressive keeps the projectile surface in a constant transition. I prefer this for soft lead because it shifts the surface providing a better seal and continuous rotation to gas expansion (ie) stability. Longer barrels have proven to out preform the shorter barrels everytime in higher twist rates. My SD is lower and I obtain more duplicate shots . My best shooter is a 6 groove between 13- 10 twist SORRY I WONT TELL YOU THE EXACT TWIST with a .500 gain 26 7/8 inch lenght , it cost several thousands of dollars to obtain this result. I have one more barrel due in next month to see if it can be improved. It's a 5 groove I will finish it at the same gain while I gain slightly more drive surface. The sad thing is your data all changes from barrel maker to maker due to their methods or processes. A shooter needs to decide what his primary application is and build to it.
 
Then shooters should buy one to try or just stick with whatever everyone’s been using for the past 100 years. I don’t think Mike needs to prove anything to anyone. Believe him or don’t. He won’t sell more Vudoos either way.
Buy a barrel and test for yourself. You might find some fun it it actually.
The question is where is the supporting evidence?
Over three months ago Mike said he "finalized the testing over two years ago." (post #175). He also said that he would make the information public soon. (post #183). I'm asking is there any data to share with shooters. If the faster twist barrel claims can be verified with evidence that would be a good thing.
 
I have to agree with your flyer statement CRPS I have viewed the same effects at higher twist rates. I must consider also if my spin drift has increased 7.38 inches at 600yds any defects would also be magnified. I have barrels piled up in the corner of my shop from 7.5 to 16 buttoned,cut, poly ratchet 2,3,4,5,6,9 groove you name it. Mr. Bush is correct in his statement on his findings , but that's for the internal profile he's using. One has to look at a broader spectrum though. That's the transition from internal to external ballistics, the stability and consistency of the projectiles transition from guided to self guided flight. Shilen solved some of this with the Ratchet rifling , it creates a larger bearing surface imparting stability to the projectile driving surface during rapid acceleration. The polygon is in likeness but not single sided , transitional or progressive keeps the projectile surface in a constant transition. I prefer this for soft lead because it shifts the surface providing a better seal and continuous rotation to gas expansion (ie) stability. Longer barrels have proven to out preform the shorter barrels everytime in higher twist rates. My SD is lower and I obtain more duplicate shots . My best shooter is a 6 groove between 13- 10 twist SORRY I WONT TELL YOU THE EXACT TWIST with a .500 gain 26 7/8 inch lenght , it cost several thousands of dollars to obtain this result. I have one more barrel due in next month to see if it can be improved. It's a 5 groove I will finish it at the same gain while I gain slightly more drive surface. The sad thing is your data all changes from barrel maker to maker due to their methods or processes. A shooter needs to decide what his primary application is and build to it.
The gain twist with lead has been of some interest to me....
My observation has been most 1-16 fall apart 350 ish yards out. I am fortunate enough to have a range out past 22lr spitting distance so often have guys who want to come out and collect data etc. I have 12" plates out past 400 yards. Everyone can make 325 some 350 few 375 the better ones 400. (Yes I know ammo...) At this point what we are looking for is to hold up better to 400 and increased consistency not nessisarly accuracy if that makes sense. It would seem from my limited experiments past 400 that could be a different ball game.

We are using all the same barrel manufacturer for our testing. They are button rifled so gain twist is out for now.

If I follow correctly your findings would say that what I would find as a optimal twist rate would/ could be different then some one with a different brand due to rifling profile and bore dimensions?
 
  • Like
Reactions: Drew M
That is absolutly correct I will tell you that Genos findings are almost identical to my research. Though I did my SD at 25 rounds. I quickly realized that the longer barrels were far more consistent. I did all of my testing without culling ammo , I believed this to be far more important so that ,when I did cull my SD should tighten up and it did I have seen a SD of 3.7 for 15 shots with 5-7 for 25 regular. I took it further by weighing each round on a .02 grain scale the Gemini 20 to determine if variance was powder , lead or brass variance. I identified each case 1-25 with its weight then the veloicty. After firing each brass was weighed and recorded the end results for 4 types of ammo were a powder or powder to primer variance. The data was self supporting as the heavier rounds turned higher velocities. I truly believe if you took a lot of ammo and cataloged it like this you could project veloicty by weight for that Lot #.
 
  • Like
Reactions: Drew M
The gain twist with lead has been of some interest to me....
My observation has been most 1-16 fall apart 350 ish yards out. I am fortunate enough to have a range out past 22lr spitting distance so often have guys who want to come out and collect data etc. I have 12" plates out past 400 yards. Everyone can make 325 some 350 few 375 the better ones 400. (Yes I know ammo...) At this point what we are looking for is to hold up better to 400 and increased consistency not nessisarly accuracy if that makes sense. It would seem from my limited experiments past 400 that could be a different ball game.

We are using all the same barrel manufacturer for our testing. They are button rifled so gain twist is out for now.

If I follow correctly your findings would say that what I would find as a optimal twist rate would/ could be different then some one with a different brand due to rifling profile and bore dimensions?
And yes you are correct 350 yds a 1-16 starts showing stability issues at 600 some bullets impact at slight angles and groups open up like a car door even with a sd of 9 or less.
 
On the weight sorting another of my friends had done a lot of testing on it for ELR and has the same results.
I have not got to that as I'm interested in what is the most consistent platform at this point.
I am doing lots of 99 shots for velocity twice at each length 5 different ammo. The issue is temp makes a big difference so got to pick my days lol. I'm not going to be looking at velocity loss as that could get skewed with temp at this point.
 
O one more thing before I lost my second chrono I used at 300 yds. I would record each group at muzzle and at 300 at the same time. Till that I'll fated day when I had the ricochet. The muzzle to 300 velocities always didnt match. This could only be derived by friction or instability.
 
If you are looking at the 12 twist barrel I would run it around 27 to 27.250" for SKLR ammo your veloicty will still be above Center x at its peak barrel , but your sd and bc will tighten up you'll like your 400 yard results.
 
  • Like
Reactions: Gleedus
O one more thing before I lost my second chrono I used at 300 yds. I would record each group at muzzle and at 300 at the same time. Till that I'll fated day when I had the ricochet. The muzzle to 300 velocities always didnt match. This could only be derived by friction or instability.
Bullet bc consistency will also account for that discrepancy
 
  • Like
Reactions: Gleedus
After more than three months, is there any data available yet about the performance of the faster twist barrels compared to the standard 1:16 barrels?
If it’s better, it should be easy to show data confirming it. If it’s hard coming up with the data, then that kind of shows that while there may be a difference, it is not a huge difference. While muzzle velocity is one thing, accuracy is another, and we are using a single variable of twist. all with variable 22lr ammo.

1:16 versus fast (1:7-9) barrels in three rifles each with five lots of ammo with 50 shots each at 200 and 300 yards, at an indoor range. And that doesn’t even address barrel length, chamber, and different ammo types.

all I know is it seems like for 22 LR there is a demon at about 190 yards. If I get a faster twist barrel in and I feel like I’m making more of the hits that I think it works. It would take a huge amount of work to prove the optimal barrel twist and length.

right now when it comes time to finishing my order for my Lilja 1x9 barrel I’m gonna go with 23 inches. I actually have two on order and maybe I’ll have them leave the other one long, since they said the barrel can always be shortened. Of course, that’s for a cz455, so does barrel mounting start to screw with longer barrels? That bullet is spending forever in a long barrel..
 
  • Like
Reactions: D_TROS
I have a 1:9 Bartlien being chambered up now at 24”. Those velocity numbers make me think I should have went a couple inches longer. Either way I will be able to provide some additional data soon.
 
The question is where is the supporting evidence?
Over three months ago Mike said he "finalized the testing over two years ago." (post #175). He also said that he would make the information public soon. (post #183). I'm asking is there any data to share with shooters. If the faster twist barrel claims can be verified with evidence that would be a good thing.
Yesterday afternoon I set at a large table in my shop sorting through numerous large tubs. 3 weeks ago I did a complete remodeling of my business office and I had all the items packed in tubs to move it out. The boss (ie) wife told me to go through it or she would throw it out , and she would have without a doubt. From within those tubs I traveled a journey from the 1940s my fathers data and notes to last month. Roughly a 80 year span , I found data and targets from the 1980s I had stowed away while in the pursuit of something ? I never have been ,one to publish data for gain (ie) books or articles . The largest portion of data was obtained, by the mear reason I know whatevers been made can be improved or made to function better. In some items this isn't the case beer will never taste better out of a can then it does a bottle. Mechanical things can be improved, I looked at all of that in front of me and in those boxes realizing it had been a road of discovery in lenght. Sometimes I met my goal sometimes I didnt ,as I thru pile after pile of notes and paper away , I came to the realization that even if it were all put to public use , there are those that would question or doubt kinda like the mask or not to mask thing we have now. Sometimes we have to just believe what we have is sufficient for the task at hand. Man I'm glad I went through those boxes I found stuff I'd been looking for for over 15 years! Plus I got rid of a ton of paper that documented successes and failures in my life.
 
The two lots of SK long range Ive used are better at long range then center x or the standard velocity SK. But Eley Contact has been better yet. Force has also been more consistent then Contact although very close. I wonder if the bigger bang helps with consistency?

But with warmer weather now the contact is at the velocity the force was in cold weather and now the contact shoots the same as the force did in the cold. I wonder if it has more to do with the optimal velocity for my barrel harmonics? Now that the force has sped up its not quite as good as before.
 
Hey Guys, thanks for resurrecting this thread and sorry I couldn't respond sooner, I'm in the wilds of Montana for another week with sporadic satellite coverage.

The timing of the resurrection is perfect, as I have my other nine twist back from Daniel Horner (after a couple years of testing). Within the next month, I'll be shooting both across two Oehler 89 systems to generate the exact data that's being asked about. This info will be coupled with what I've already developed, so hang on a little longer and I'll be back in touch on this.

MB
 
I did come up with a awesome idea last night for a one of a kind match that would bring out the best of the best ? We could call it the 2022 Mega Money Match kinda like a Super ARA match target would be simular but scaled up, 3 sighters with 25 scoring shots any position with a 30 minute time limit. All ammo would have to be factory no roll yur own , any 22 rimfire in long rifle only gun would be required to be full stocked no rail or sled guns. Bipod or mechanical bag for front rest no attachments over or too the stock or rifle. Shooter may use 1 rear support as long as it was not mechanically adjustable 3 wind flags would be allowed only ,at the yardage of your choice spotters allowed. The match itself would take proably 2-3 days. The 1st day would be a meet and greet ie. Bar B Que and rifle zeroing. Now heres the catch you bring 26 $100 Bill's with you 1 is the entry fee due the 1st day the other 25 will be attached to a ARA simulated target 600 yds down range. Their your Bullseyes scoring will be any bill that has been touched by any number of rounds may be removed and put back in the shooters pocket this is what you've retained for your skills. The remaining money from all targets is collected and put into a pot it will be divided up by a precentage for the shooters abilities. Shoot offs will be done at alternate yardage 1 sighter next shot score. 100 people show up $250,000 200 show $500,000 up for grabs. I dont think everyone will remove all their 25 Bill's and put them back in their pockets so say everyone gets 15 each back that leaves $100,000 in the pot to be divided up among the shooters by percentages and shoot offs you still could leave with more then you came with just not what you actually brought kinda keep a honest man honest! Then there would be all the sponsor stuff too and the top 30% of shooters would have to disclose their exact builds putting to bed the mystery!
Whatcha think?
 
  • Like
Reactions: Seymour Fish
No I load my own with great success but that's not available to everyone and it does not dispel the myth of Factory Ammo in various twist rates for best results. I'm in the process soon of converting my RIMX to CF in 22lr but Robertsons wants to much in my opinion for 22lr c/f brass and they would be sized out and chambered for factory .224 bullets, but hey i've always been a sucker for side line events and I'm sure I could drag a extra stick with me for sure.
 
Scared to go up against handloaded ammo? Lol
Its not the going up against handloaded ammo that is the concern. The issues is that the guys who CURRENTLY are reloading have a lot more experience and knowledge relating to 22lr ELR and even if they had to shoot factory ammo would have the leg up on the rest of us goons....
 
WHAT! ? we gotta drop the Bullseye value down to $20 , $10 ,$5 or $1.00 to encourage participants to come forth ! O I see we gotta have rollurowns in there , ok will do it , but bullets have to be copper alloys no Colorado blends of paper n grass I dont wanna get shot in the Arse !😂🤣😅🤣😂😉
 
No I load my own with great success but that's not available to everyone and it does not dispel the myth of Factory Ammo in various twist rates for best results. I'm in the process soon of converting my RIMX to CF in 22lr but Robertsons wants to much in my opinion for 22lr c/f brass and they would be sized out and chambered for factory .224 bullets, but hey i've always been a sucker for side line events and I'm sure I could drag a extra stick with me for sure.
'O' one more thing Geno it will have to be pretty close to me , the match that is , I dont wanna drag a hole in my bed pan or run otta depends got a pretty hair trigger ! 😋
 
I did come up with a awesome idea last night for a one of a kind match that would bring out the best of the best ? We could call it the 2022 Mega Money Match kinda like a Super ARA match target would be simular but scaled up, 3 sighters with 25 scoring shots any position with a 30 minute time limit.... ...The 1st day would be a meet and greet ie. Bar B Que and rifle zeroing. Now heres the catch you bring 26 $100 Bill's with you 1 is the entry fee due the 1st day the other 25 will be attached to a ARA simulated target 600 yds down range. Their your Bullseyes scoring will be any bill that has been touched by any number of rounds may be removed and put back in the shooters pocket this is what you've retained for your skills. Whatcha think?

Interesting idea. If? this takes wings, I have a proposition. I have at our club access to a 600y range which could support the event. We would need club approval for its use but it is here in KY so accessible from many parts of the country. We also have a pretty darn good Southern BBQ restaurant owned by one of our marksmen who could cater the BBQ for us with some fine porcine cuisine. I for one am more of the 50y Benchrest crowd and have never shot my 22's past 300y. Not sure I could hit a car door or a barn door for that mater at 600y but am willing to try. The thought of using Benjamins for the bulls is pricey for my taste. Am fine with the $100 entry fee but am thinking that we might get a few more takers if we were using $20's for the tgts, just sayin, lol.

As for adding to the anecdotal BS on the internet. I shoot ARA Factory BR matches and off and on have had some limited success at it since the new class began last year. I had to obtain a new rifle for the 2021 class which is a CZ457 with the varmint precision bbl profile bbl which is reported by the Mfg to be of the hammer forged type. Mine is 24" and the claimed twist as far as I know is 1:16" which is std. It has a pronounced choke at the last 2" of the muzzle but I have not slugged and measured it.

Early in the 2021 season I was shooting slower ammo in the 320-323M/s range with good results in both warmish (65 deg F) and cold weather (sub freezing) and recorded two perfect scores in non-sanctioned practice matches and four in sanctioned match play. Later in the year, I ran out of that ammo and switched to 325M/s published velocity (all Lapua CX or Midas). Results suffered slightly but still recorded a few 2500's with it. I had access to 326, 327 and 328 speed ammo as well as some Polar Bi ammo that was marked 335M/s. The Polar ammo shot brilliantly in the early spring with temps running 30-45 deg F. Point being that the rifle was not very ammo sensitive.

I had some 327 ammo that would not shoot in anything well in the winter but now that summer is almost upon us it is shooting great. In one recent match, I had to shoot three cards in a downpour and found that my usual 325 spd ammo was not longer stable. I theorize that the random dispersion of the projectile was coming from both actual rain drops impacting the projectile and the cooler, moisture laden air was causing POI dispersion in all directions and thus was not possible to adjust my POA to compensate since one shot would go low right and the next might go low left, then high, etc. The wind was calm at the time so the flags were of little value. After making a mess of my 4th card, I changed ammo lots to the faster 327 spd. (~1073 fps) hoping to see an improvement. The slightly faster ammo seemed to stabilize better in these unstable atmospheric conditions. Result was two 2450 scores and the one dropped shot on each was so close that it was only visible under lighted magnification. The use of the slightly faster ammo in this case resulting in better performance.

When there is either natural or artificial backlighting of the range, I can sometimes see my bullets as they travel downrange. They arc up and curve to the right most of the time, just like a pitcher's curve ball. The arc at only 50y is significant. Even on a good day, it seems to wobble significantly along its path and appears to be only marginally stable. But often when I am competing in matches with dead calm zero wind, I will see the bullet's path deviate into more of a screwball path where it will arc up and to the right but then rapidly continue to curve in a clockwise manner and instead of hitting at the intended, zero'ed POI, it curves down much more and lands low in the 5,6,7 o'clock region of the bull. This is also painfully random in nature as sighters both before and after often hit the center dot of the bull. I am not claiming I know "Why" this is happening but would love to understand it better. Am also wondering if a faster twist bbl might eliminate some of this sort of random instability.
More old wives and old marksmen tales: I was just at the VA state ARA championships at Kettlefoot. The Triple Crown is today. In discussing this issue with some of the old heads of the sport, some claim that traditional twist 22bbls stabilize better with a little bit of wind. I have heard expert shooters say this often and have personally experienced it. A gun and ammo combo that is lights out with a slight steady breeze often goes wonky in dead calm conditions. Now I know that dead calm does not mean there is no air movement. Just watch the smoke from the muzzles to see that the air is moving. Small eddy currents are rising or falling depending on if the sun is out or not or moisture evaporating from a rain earlier, etc. But these dead calm conditions are diabolical to shoot in when the tgt is soooo small. Any of you ballisticians or Astro physics PhD's have an explanation? Or better yet, how can I control it?

MB - Love your razor sharp humor. Am proud of the work you and your colleagues are doing at VuDoo. Having worked in technical R&D in the past, I can appreciate the difficulty in performing design of experiments with a process that contains so many hard to manage variables. I am still looking for that ARA eligible Factory class legal VuDoo, so we can once more place an American rifle on the top podium. Maybe with a 1:9" twist on it too? Keep up the quality work testing and learning and pushing the envelope of the state of the art. People laughed at the Wright Brothers also. A quote overheard being mumbled by some old Calcified gunsmith at the range "If men were meant to shoot 22lr rimfires at 400 & 500y tgts they would have been born with fast twist barrels"

Irish
 
Last edited:
That's cool I love Kentucky, beautiful country and GREAT FOLKS ! Did the Corvette anniversary deal up there in 99 at the plant never seen so many Vettes in my life. Sometimes things that aren't broke dont need to be fixed. I'm just glad I dont have to carry a bag phone around anymore ! I could do Kentucky been wanting to see the Ark anyhow.
 
what kind of gain are we talking about? On a soft lead bullet with a gain twist kind of have the effective smoothing out the grooves and lands marks but still in parting spin on the bullet?
I have to agree with your flyer statement CRPS I have viewed the same effects at higher twist rates. I must consider also if my spin drift has increased 7.38 inches at 600yds any defects would also be magnified. I have barrels piled up in the corner of my shop from 7.5 to 16 buttoned,cut, poly ratchet 2,3,4,5,6,9 groove you name it. Mr. Bush is correct in his statement on his findings , but that's for the internal profile he's using. One has to look at a broader spectrum though. That's the transition from internal to external ballistics, the stability and consistency of the projectiles transition from guided to self guided flight. Shilen solved some of this with the Ratchet rifling , it creates a larger bearing surface imparting stability to the projectile driving surface during rapid acceleration. The polygon is in likeness but not single sided , transitional or progressive keeps the projectile surface in a constant transition. I prefer this for soft lead because it shifts the surface providing a better seal and continuous rotation to gas expansion (ie) stability. Longer barrels have proven to out preform the shorter barrels everytime in higher twist rates. My SD is lower and I obtain more duplicate shots . My best shooter is a 6 groove between 13- 10 twist SORRY I WONT TELL YOU THE EXACT TWIST with a .500 gain 26 7/8 inch lenght , it cost several thousands of dollars to obtain this result. I have one more barrel due in next month to see if it can be improved. It's a 5 groove I will finish it at the same gain while I gain slightly more drive surface. The sad thing is your data all changes from barrel maker to maker due to their methods or processes. A shooter needs to decide what his primary application is and build to it.
@FromMyColdDeadHand
The gain mentioned was .500 in the post above by @Rimdenter & wow he has some interesting information in there for us to take in.
The gain twist with lead has been of some interest to me....
My observation has been most 1-16 fall apart 350 ish yards out. I am fortunate enough to have a range out past 22lr spitting distance so often have guys who want to come out and collect data etc. I have 12" plates out past 400 yards. Everyone can make 325 some 350 few 375 the better ones 400. (Yes I know ammo...) At this point what we are looking for is to hold up better to 400 and increased consistency not nessisarly accuracy if that makes sense. It would seem from my limited experiments past 400 that could be a different ball game.

We are using all the same barrel manufacturer for our testing. They are button rifled so gain twist is out for now.

If I follow correctly your findings would say that what I would find as a optimal twist rate would/ could be different then some one with a different brand due to rifling profile and bore dimensions?
@CRPS Shooter
I've also been thinking about gain twist & rimfire,
Thinking that it will be looked at more often in the future seeing as it is looking promising in centrefire & machining capability's are pretty good these days.
Also agree from Rimdenter's post that optimal twist rate could vary between barrel manufacturer's, even rifling types for the same bullet & that makes sense to me.
 
It got too hot and too busy this summer. My 457 with Lilja barrel (1:9) wasn’t as good as I had hoped in its first outing, butI think I have some head spacing work to do. Might get out on Sunday to do some work up on it.