22lr twist rate advantages

[rockranger77]

What's been the most fun about my rimfire journey has been hearing lots of people say, especially early on, "that'll never work." And then I heard all the reasons why it would never work and it was mostly the, "well, for the last hundred years, blah, blah, blah." Clearly, they were wrong and it's been amusing.

The fast twist debate has been no different and I truly don't care, I have nothing to prove and can continue to sit on the data....I have more than enough to do. If one wants to rant about data and the last 100 or so years....so what, doesn't motivate me in the least. The ones that motivate me are the ones excited enough to jump right in and live beyond the last 100 or so years. They're the ones that give me reason to share....

MB

MB

I have a question. Is the 22 inch length with 1:9 twist barrel harmonics in your opinion? The reason i ask is because i have a Green Mountain barrel that i had threaded on a 10/22 that is 20" and 1:9 twist and was advertised as a subsonic barrel by them about 15yrs ago. I was asking because I was wondering if I could add a 2" machined thread protector and maybe pull some accuracy out of the gun. Just curious about your professional opinion .

Thanks for your time
SE

 

[RAVAGE88]

MB

I have a question. Is the 22 inch length with 1:9 twist barrel harmonics in your opinion? The reason i ask is because i have a Green Mountain barrel that i had threaded on a 10/22 that is 20" and 1:9 twist and was advertised as a subsonic barrel by them about 15yrs ago. I was asking because I was wondering if I could add a 2" machined thread protector and maybe pull some accuracy out of the gun. Just curious about your professional opinion .

Thanks for your time
SE

Hey Dude, I remember those. Primarily, they were intended for the 60 grain truly subsonic (900 fps) rounds, which may not be as prevalent now. I still have a lot of that 60 grain stuff laying around, but I never shoot it. The Lapua, SK and other 40 grain match quality ammo is Standard Velocity (1080-ish fps) which, depending upon elevation, is still below the speed of sound.

No sir, adding an extension to the barrel will not help you in the accuracy department....

MB

 

[rockranger77]

Hey Dude, I remember those. Primarily, they were intended for the 60 grain truly subsonic (900 fps) rounds, which may not be as prevalent now. I still have a lot of that 60 grain stuff laying around, but I never shoot it. The Lapua, SK and other 40 grain match quality ammo is Standard Velocity (1080-ish fps) which, depending upon elevation, is still below the speed of sound.

No sir, adding an extension to the barrel will not help you in the accuracy department....

MB

Thanks for the quick response and for the advice. Yeah I bought it to shoot the 60 grain stuff and I have a few of those left laying around but the accuracy is far from good. Kills armadillos really good. Thanks again and I hope that things are going well for all of you in your line of work, I know that the powers to be are not on our side for sure.

SE

 

[RAVAGE88]

Thanks for the quick response and for the advice. Yeah I bought it to shoot the 60 grain stuff and I have a few of those left laying around but the accuracy is far from good. Kills armadillos really good. Thanks again and I hope that things are going well for all of you in your line of work, I know that the powers to be are not on our side for sure.

SE

I never had much success in the accuracy dept from the 60 grainers either, but they sure do hit hard. Things are going well for us and we're navigating the tumultuous parts with no real bums to speak of. Take care and reach out anytime if you need anything.

MB

 

[FromMyColdDeadHand]

Just got the word that Lilja finished their run of 1x9 twist barrels for CZ455/457. They have one unsold if anyone is interested. Sounds like they had a lot of interest in them. I'm getting two both, 22 inches. My original thought was upgrading my son's 455 with one and making a pure LR22 out of the other. But his 455 is plenty accurate and it only has a 10x scope on it. Just a great all-around plinker. I might whack out a 457 with one of these barrels and then decide if I want to duplicate it or sell it and go with a full Voodo set up.

 

[CBeck]

24” fast twist Bartlien

 

[FromMyColdDeadHand]

24” fast twist Bartlien

How fast?

 

[CBeck]

9 twist

 

[daluka69]

24” fast twist Bartlien View attachment 7649437

Would you mind sharing your experience with this fast twister?

 

[JBoomhauer]

Might as well throw my fast twist to the mix.

26” 10tw

 

[RAVAGE88]

Ok, so an update on the testing for those of you not following along on Instagram (@vudoo_labs). I'm headed down to Alabama to Boone Ballistics on June 22nd to start testing on the 23rd. I'm taking three rifles, one 16 twist and two nine twist. My buddies from Lothar Walther are bringing a couple 12 twist and possibly a couple nine twist. We'll be shooting Lapua almost exclusively with the exception of one of the tests where we need super sonic ammo. Eley falls apart after 50 yards and my Vudoo's won't close on most Eley ammo, which is just fine with me.

The ballistics range is a twin Oehler 89 System, so no lack of capability to gather sound data and the protocol has been drafted and approved. Should be a good time and most certainly a great opportunity for the rimfire community.

MB

 

[daluka69]

Would still like to hear some feedback from the guys with the fast twist barrels. The pics are cool, but sharing info on real world results would be beneficial

 

[RAVAGE88]

Would still like to hear some feedback from the guys with the fast twist barrels. The pics are cool, but sharing info on real world results would be beneficial

The data is forthcoming, as I laid out above. Most with nine twist rifles haven't had them long, but I'm sure they'll share experiences when they have a handle on getting rifles setup and shooting well....no different than any other rimfire.

MB

 

[CBeck]

Would you mind sharing your experience with this fast twister?

My experience so far is I picked up the barreled action from the ffl today, put it together, and shot 150 rounds from 50 to 75 yards. So far it’s shoots just as good as my 16 twist Vudoo at those distances. I’ll report back once I actually have useful experience.

 

[ZG47A]

I never had much success in the accuracy dept from the 60 grainers either, but they sure do hit hard. Things are going well for us and we're navigating the tumultuous parts with no real bums to speak of. Take care and reach out anytime if you need anything.

MB

A local gun industry guy had a factory tour of the Aguila plant. He said that the 60 grain ammo was being loaded on the standard .22 Short line and powder (smokeless propellant to be precise) was falling out of the cases as they moved along. That being said, they shot reliably out to 20m BUT I definitely had some sideways bullet holes when I tried them at 25 yards (22.86m).

 

[JBoomhauer]

Here is my first 300y group with the fast twist.

Keep in mind I got this rifle Wednesday, and have not tuned or really tested much yet.

Dialed 13.9 mil, impacted .9 high. 13.0 Total elevation vs 14.5 with the cz on a previous day. So there may be something to the BC thing. I’d have to shoot side by side in the same conditions to see for sure.

25 shot group measures 10” high 6.5” wide. Held center and ignored wind and elevation.

 

[KnowNothing256]

Eley falls apart after 50 yards and my Vudoo's won't close on most Eley ammo, which is just fine with me.

Interesting. A few questions:

1) When you say it falls apart, do you mean basically all the Eley lines, or just one or two such as the top-line varieties?
2) Is this just in the Vudoos, or have you/others seen this consistently across various platforms?
3) Is it just a MV issue do you think (vertical dispersion), or is it more generally spread on the target?
4) To confirm when you say they won’t close, you mean there’s insufficient headspace, i.e., the rims are thicker than the Vudoos will tolerate?

Thanks for all the info, watching with great curiosity.

 

[RAVAGE88]

Interesting. A few questions:

1) When you say it falls apart, do you mean basically all the Eley lines, or just one or two such as the top-line varieties?
2) Is this just in the Vudoos, or have you/others seen this consistently across various platforms?
3) Is it just a MV issue do you think (vertical dispersion), or is it more generally spread on the target?
4) To confirm when you say they won’t close, you mean there’s insufficient headspace, i.e., the rims are thicker than the Vudoos will tolerate?

Thanks for all the info, watching with great curiosity.

1). Great groups at 50 yards, doesn't compare to Lapua groups beyond 50 yards
2). I only shoot Vudoo's
3). There's a difference in projectile design between Lapua and Eley
4). The Vudoo chamber is designed around Lapua. Eley headspace and physical case dimensions differ from Lapua and I set my rifles up very specifically to Lapua.

No worries, reach out anytime.

MB

 

[KnowNothing256]

1). Great groups at 50 yards, doesn't compare to Lapua groups beyond 50 yards
2). I only shoot Vudoo's
3). There's a difference in projectile design between Lapua and Eley
4). The Vudoo chamber is designed around Lapua. Eley headspace and physical case dimensions differ from Lapua and I set my rifles up very specifically to Lapua.

No worries, reach out anytime.

MB

Got it. But one last check, you mean that *all* Eley ammo falls apart past 50 yds, including Tenex etc., not just the cheaper varieties?

 

[RAVAGE88]

Got it. But one last check, you mean that *all* Eley ammo falls apart past 50 yds, including Tenex etc., not just the cheaper varieties?

The two tested as part of this latest series of tests was Match and Tenex. Can't speak to *all* Eley....

MB

 

[KnowNothing256]

The two tested as part of this latest series of tests was Match and Tenex. Can't speak to *all* Eley....

MB

Good enough for me, thanks a ton.

 

[Biscuits]

I'd say that if 1 in 9" works with a 22 inch barrel and not with a 18 inch barrel..... then that just means that we don't have any useful data. Anything could be going on. Maybe the crown in the 18 inch barrel wasn't cut straight. Maybe the crown in the 22 inch barrel just happened to be the most symmetrical perfect crown ever. If a relatively small change in barrel length when the 22 round has already developed its maximum velocity causes a big change, then I doubt it is down to twist rate.

 

[RAVAGE88]

I'd say that if 1 in 9" works with a 22 inch barrel and not with a 18 inch barrel..... then that just means that we don't have any useful data. Anything could be going on. Maybe the crown in the 18 inch barrel wasn't cut straight. Maybe the crown in the 22 inch barrel just happened to be the most symmetrical perfect crown ever. If a relatively small change in barrel length when the 22 round has already developed its maximum velocity causes a big change, then I doubt it is down to twist rate.

No sir, sorry, but you're wrong. First, there's more data on this than you're currently aware of and that's on purpose. Second, the crown has nothing to do with the difference in why the 18" didn't work and the 22" and longer barrels do. Remember that we're working with a soft lead bullet here and centrifugal pressure is higher due to an increase in angular velocity. With that, there's something useful about the extra length that has nothing to do with full powder burn.

MB

 

[Biscuits]

No sir, sorry, but you're wrong. First, there's more data on this than you're currently aware of and that's on purpose. Second, the crown has nothing to do with the difference in why the 18" didn't work and the 22" and longer barrels do. Remember that we're working with a soft lead bullet here and centrifugal pressure is higher due to an increase in angular velocity. With that, there's something useful about the extra length that has nothing to do with full powder burn.

MB

I did a rough calculation and got an angular velocity of 8520 rad/s with a 9 inch twist and ammo just under the speed of sound (I used 310m/s). This gives a centripetal acceleration of about 202,000m/s^2. This is more than the linear acceleration of the bullet down the barrel which is about 105,000m/s^2 (assuming linear acceleration down an 18 inch barrel). For a 16 inch barrel, the centripetal acceleration is considerably less, about 64,000m/s^2. So I can see you get a lot more centripetal acceleration out of a fast twist rate. I'm still struggling to see how a 18 or a 22 inch barrel would make any difference though.

A comparison with 38/357s lever action rifles, where unjacketed lead bullets are common:

These 38/357s have the same 16 inch twist rate as a standard 22 long rifle, but with a larger diameter bullet. I've chrono'd Magtec 357 lead ammo out of my 357 rifle and from memory somewhere it is over 450 m/s muzzle velocity. The higher velocity combined with a larger bullet gives you an even higher centripetal acceleration than the 22 lr bullet out of a 9 inch barrel which I described in the first paragraph. However, you can also shoot 38 special. Same bullet, half the muzzle velocity, therefore one-quarter the centripetal acceleration (1/4 as centripetal acceleration is proportional to the square of angular velocity). I don't really see any paricular accuracy difference between 38 special and 357 magnum out of the same gun, despite the centripetal accelerations on the edge of the soft lead bullet approximately matching that of the 22lr out of a 9 inch and 16 inch twist barrel.

Here's my maths. 22lr 9-inch twist first, then 22lr 16 inch twist, then 357 magnum

22LR - fast 9 inch twist
Twist rate	9​	[inches]
	0.2286​	[m]
Bullet diameter	0.22​	[in]
	0.005588​	[m]
Bullet radius	0.002794​	[m]
Muzzle velocity	310​	[m/s]
Rev/sec	1356.1​	rps
Rev/min	81364.8​	rpm
Angular velocity	8520.5​	rad/s
Acceleration at edge of bullet	202841.6​	[m/s^2]
Linear acceleration of bullet in barrel
Barrel length	18​	[inch]
	0.4572​	[m]
Acceleration	105096.2​	[m/s^2]

22LR
Twist rate	16​	[inches]
	0.4064​	[m]
Bullet diameter	0.22​	[in]
	0.005588​	[m]
Bullet radius	0.002794​	[m]
Muzzle velocity	310​	[m/s]
Rev/sec	762.8​	rps
Rev/min	45767.7​	rpm
Angular velocity	4792.8​	rad/s
Acceleration at edge of bullet	64180.4​	[m/s^2]
Linear acceleration of bullet in barrel
Barrel length	18​	[inch]
	0.4572​	[m]
Acceleration	105096.2​	[m/s^2]
357 MAGNUM LEVER ACTION
Twist rate	16​	[inches]
	0.4064​	[m]
Bullet diameter	0.38​	[in]
	0.009652​	[m]
Bullet radius	0.004826​	[m]
Muzzle velocity	450​	[m/s]
Rev/sec	1107.3​	rps
Rev/min	66437.0​	rpm
Angular velocity	6957.3​	rad/s
Acceleration at edge of bullet	233595.6​	[m/s^2]
Linear acceleration of bullet in barrel
Barrel length	18​	[inch]
	0.4572​	[m]
Acceleration	221456.7​	[m/s^2]

​

 

[RAVAGE88]

I did a rough calculation and got an angular velocity of 8520 rad/s with a 9 inch twist and ammo just under the speed of sound (I used 310m/s). This gives a centripetal acceleration of about 202,000m/s^2. This is more than the linear acceleration of the bullet down the barrel which is about 105,000m/s^2 (assuming linear acceleration down an 18 inch barrel). For a 16 inch barrel, the centripetal acceleration is considerably less, about 64,000m/s^2. So I can see you get a lot more centripetal acceleration out of a fast twist rate. I'm still struggling to see how a 18 or a 22 inch barrel would make any difference though.

A comparison with 38/357s lever action rifles, where unjacketed lead bullets are common:

These have the same 16 inch twist rate as a standard 22 long rifle, but a larger diameter bullet. I've chrono'd Magtec 357 lead ammo out of my 357 rifle and from memory somewhere over 450 m/s muzzle velocity. The higher velocity combined with a larger bullet gives you an even higher centripetal acceleration than the 22 lr bullet which I described in the first paragraph. However, you can also shoot 38 special. Same bullet, half the muzzle velocity, therefore half the centripetal acceleration. I don't really see any paricular accuracy difference between 38 special and 357 magnum out of the same gun, despite the centripetal accelerations on the edge of the soft lead bullet approximately matching that of the 22lr out of a 9 inch and 16 inch twist barrel.

Here's my maths. 22lr first, then 357 magnum

22LR
Twist rate	16​	[inches]
	0.4064​	[m]
Bullet diameter	0.22​	[in]
	0.005588​	[m]
Bullet radius	0.002794​	[m]
Muzzle velocity	310​	[m/s]
Rev/sec	762.8​	rps
Rev/min	45767.7​	rpm
Angular velocity	4792.8​	rad/s
Acceleration at edge of bullet	64180.4​	[m/s^2]
Linear acceleration of bullet in barrel
Barrel length	18​	[inch]
	0.4572​	[m]
Acceleration	105096.2​	[m/s^2]
357 MAGNUM LEVER ACTION
Twist rate	16​	[inches]
	0.4064​	[m]
Bullet diameter	0.38​	[in]
	0.009652​	[m]
Bullet radius	0.004826​	[m]
Muzzle velocity	450​	[m/s]
Rev/sec	1107.3​	rps
Rev/min	66437.0​	rpm
Angular velocity	6957.3​	rad/s
Acceleration at edge of bullet	233595.6​	[m/s^2]
Linear acceleration of bullet in barrel
Barrel length	18​	[inch]
	0.4572​	[m]
Acceleration	221456.7​	[m/s^2]

​

Awesome Dude, now we’re talkin’ . Welcome to the wonderful world of Rimfire where the target gives you an answer you have to work hard to understand.

MB

 

[daluka69]

My Lord…. I love this stuff. I’m dying to hear the full story on this fast twist testing. Very interested

 

[grauhanen]

But one last check, you mean that *all* Eley ammo falls apart past 50 yds, including Tenex etc., not just the cheaper varieties?

Not all Eley ammo will perform the same way past 50 yards. Eley and other match ammo performance beyond 50 will vary by lot. Some lots will be better than others, which is to say that some will be very good, others won't.

 

[RAVAGE88]

Not all Eley ammo will perform the same way past 50 yards. Eley and other match ammo performance beyond 50 will vary by lot. Some lots will be better than others, which is to say that some will be very good, others won't.

Within a specific shooting discipline, limited to 50 yards, you are correct. For the purposes of the performance based discussion in this thread, lot number isn't relevant inasmuch as bullet flight is. There's a distinct difference in the design between the Eley projectile and the Lapua projectile and efficient flight beyond 50 doesn't favor the Eley projectile.

MB

 

[FromMyColdDeadHand]

Awesome Dude, now we’re talkin’ . Welcome to the wonderful world of Rimfire where the target gives you an answer you have to work hard to understand.

MB

22lr and Economics- where theory comes after the reality..

Not to add any kind of extra interations to probably your already large test plan, but it would be interesting to know if suppressing the faster twist has any effect.

Frankly, with my 26 inch barrel, with subs, and a bolt gun- when outside, even under cover- I think a suppressor for hearing doesn't add much. Shorter barrel, supers, and inside- different story.

Thanks for all your work!

 

[Rimdenter]

Within a specific shooting discipline, limited to 50 yards, you are correct. For the purposes of the performance based discussion in this thread, lot number isn't relevant inasmuch as bullet flight is. There's a distinct difference in the design between the Eley projectile and the Lapua projectile and efficient flight beyond 50 doesn't favor the Eley projectile.

MB

Tenex at 600 yds was like shooting for HOPE ! the lot of SKLR I shoot is for hitting what you shoot at .

 

[RAVAGE88]

Tenex at 600 yds was like shooting for HOPE ! the lot of SKLR I shoot is for hitting what you shoot at .

MB

 

[grauhanen]

Within a specific shooting discipline, limited to 50 yards, you are correct. For the purposes of the performance based discussion in this thread, lot number isn't relevant inasmuch as bullet flight is. There's a distinct difference in the design between the Eley projectile and the Lapua projectile and efficient flight beyond 50 doesn't favor the Eley projectile.

I'm not sure if the view is that only in a fast twist barrel does the design of the Eley bullet cause it to be at a disadvantage at longer distances or if it's also supposed to be at a disadvantage in standard twist barrels. If the point is with regard to fast twist barrels only then what follows can be disregarded.

In standard twist barrels there's reason to believe that the Eley bullet design is not a disadvantage and that bullet flight will vary by lot.

While Lapua uses a round nose bullet, Eley uses a flat nose bullet design on its top tier ammo. Does that necessarily disqualify Eley ammo from having good performance at longer distances? It doesn't seem to do so with standard twist barrels.

In barrels tested at the Lapua testing facility, the same Lapua bullet design is used in all testing and performance at 100 meters varies by lot. The same can be said for Eley testing results. In other words, bullet flight varies by lot. Some lots produce better results than others at 100. Those are the lots that are desirable for shooting at further distances. Lots that performed less well at 100 aren't going to predictably improve their performance as they go further out.

Perhaps Eley flat nose bullets may be at a disadvantage in a Vudoo with a Lapua-friendly chamber -- I don't know. But there are Eley shooters who do believe the UK ammo is a good performer with a Vudoo rifle. See, for example, https://eley.co.uk/shooting-long-range-22lr-competition-craze/

Of course this Eley/Vudoo endorsement should be regarded with some caution as by itself it doesn't prove anything.

More interesting is a 2018 200 yard record for a five-shot-group shot by John Lavaring in Australia. Little is said about the rifle or barrel, but presumably it's a standard twist. The 200 yard group was .93" or .44 MOA. The ammo was Eley Tenex. See http://bulletin.accurateshooter.com...acy-from-australian-22-lr-rifle-at-200-yards/ This is strong evidence that bullet shape didn't disadvantage the results.

Again, if the view is that the Eley bullet shape fails to be competitive at distances beyond 50 yards/meters in fast twist Vudoo-chamber barrels only, then the above can be disregarded.

 

[Rimdenter]

I'm not sure if the view is that only in a fast twist barrel does the design of the Eley bullet cause it to be at a disadvantage at longer distances or if it's also supposed to be at a disadvantage in standard twist barrels. If the point is with regard to fast twist barrels only then what follows can be disregarded.

In standard twist barrels there's reason to believe that the Eley bullet design is not a disadvantage and that bullet flight will vary by lot.

While Lapua uses a round nose bullet, Eley uses a flat nose bullet design on its top tier ammo. Does that necessarily disqualify Eley ammo from having good performance at longer distances? It doesn't seem to do so with standard twist barrels.

In barrels tested at the Lapua testing facility, the same Lapua bullet design is used in all testing and performance at 100 meters varies by lot. The same can be said for Eley testing results. In other words, bullet flight varies by lot. Some lots produce better results than others at 100. Those are the lots that are desirable for shooting at further distances. Lots that performed less well at 100 aren't going to predictably improve their performance as they go further out.

Perhaps Eley flat nose bullets may be at a disadvantage in a Vudoo with a Lapua-friendly chamber -- I don't know. But there are Eley shooters who do believe the UK ammo is a good performer with a Vudoo rifle. See, for example, https://eley.co.uk/shooting-long-range-22lr-competition-craze/

Of course this Eley/Vudoo endorsement should be regarded with some caution as by itself it doesn't prove anything.

More interesting is a 2018 200 yard record for a five-shot-group shot by John Lavaring in Australia. Little is said about the rifle or barrel, but presumably it's a standard twist. The 200 yard group was .93" or .44 MOA. The ammo was Eley Tenex. See http://bulletin.accurateshooter.com...acy-from-australian-22-lr-rifle-at-200-yards/ This is strong evidence that bullet shape didn't disadvantage the results.

Again, if the view is that the Eley bullet shape fails to be competitive at distances beyond 50 yards/meters in fast twist Vudoo-chamber barrels only, then the above can be disregarded.

You said it ( A ) group and yes I've got exceptional groups at 2 and 300 yds with eley ,but not consistantly and past that hang it up. It didnt matter what twist or chamber I tried the rounder nose projectiles out performed it.

 

[RAVAGE88]

I'm not sure if the view is that only in a fast twist barrel does the design of the Eley bullet cause it to be at a disadvantage at longer distances or if it's also supposed to be at a disadvantage in standard twist barrels. If the point is with regard to fast twist barrels only then what follows can be disregarded.

In standard twist barrels there's reason to believe that the Eley bullet design is not a disadvantage and that bullet flight will vary by lot.

While Lapua uses a round nose bullet, Eley uses a flat nose bullet design on its top tier ammo. Does that necessarily disqualify Eley ammo from having good performance at longer distances? It doesn't seem to do so with standard twist barrels.

In barrels tested at the Lapua testing facility, the same Lapua bullet design is used in all testing and performance at 100 meters varies by lot. The same can be said for Eley testing results. In other words, bullet flight varies by lot. Some lots produce better results than others at 100. Those are the lots that are desirable for shooting at further distances. Lots that performed less well at 100 aren't going to predictably improve their performance as they go further out.

Perhaps Eley flat nose bullets may be at a disadvantage in a Vudoo with a Lapua-friendly chamber -- I don't know. But there are Eley shooters who do believe the UK ammo is a good performer with a Vudoo rifle. See, for example, https://eley.co.uk/shooting-long-range-22lr-competition-craze/

Of course this Eley/Vudoo endorsement should be regarded with some caution as by itself it doesn't prove anything.

More interesting is a 2018 200 yard record for a five-shot-group shot by John Lavaring in Australia. Little is said about the rifle or barrel, but presumably it's a standard twist. The 200 yard group was .93" or .44 MOA. The ammo was Eley Tenex. See http://bulletin.accurateshooter.com...acy-from-australian-22-lr-rifle-at-200-yards/ This is strong evidence that bullet shape didn't disadvantage the results.

Again, if the view is that the Eley bullet shape fails to be competitive at distances beyond 50 yards/meters in fast twist Vudoo-chamber barrels only, then the above can be disregarded.

There's a lot of subjectivity in this particular topic and my aim isn't to slight or promote any one brand over another. I'm quite certain one could dig through various archives and find any number of different things published, but there are far more people shooting than there are people writing about shooting. Frankly, I pay more attention to those shooting as their feedback is quite valuable and leads to advancement in our sport. If what shooters are doing is pressing companies in the industry to innovate, then we all win and the area that needs to catch up a little is ammunition. I've had greater success shooting a 22LR at distance with Lapua than I have Eley and this was before I designed the chamber used at Vudoo.

As I stated above, the target gives you answers that you have to work to understand.

MB

 

[Rimdenter]

You said it ( A ) group and yes I've got exceptional groups at 2 and 300 yds with eley ,but not consistantly and past that hang it up. It didnt matter what twist or chamber I tried the rounder nose projectiles out performed it.

Oh and the gun was a sled ,barrel block and all. Wonder what it would have looked like off a bi-pod and bag ? Never the less a group is a group. I truly admire the ARA guys just dont have the patience for that.

 

[grauhanen]

There's a lot of subjectivity in this particular topic and my aim isn't to slight or promote any one brand over another. I'm quite certain one could dig through various archives and find any number of different things published, but there are far more people shooting than there are people writing about shooting. Frankly, I pay more attention to those shooting as their feedback is quite valuable and leads to advancement in our sport. If what shooters are doing is pressing companies in the industry to innovate, then we all win and the area that needs to catch up a little is ammunition. I've had greater success shooting a 22LR at distance with Lapua than I have Eley and this was before I designed the chamber used at Vudoo.

As I stated above, the target gives you answers that you have to work to understand.

MB

It's obvious there's a lot of subjectivity in this topic and in so many other relating to rimfire. As suggested, it's possible to dig up many examples of Eley ammo performing well at long distances. No doubt those shooters would say the same about their success shooting .22LR at distance as some would say of Lapua. And there's the rub: shooters will advocate for what works for them, empirical evidence based on observation. It doesn't admit contrary data because by its nature and from practical purposes it's can't be as convincing.

In any case, it's timely to note that many shooters report that currently Lapua produces more consistent ammo than Eley. But this changes over time.

 

[RAVAGE88]

It's obvious there's a lot of subjectivity in this topic and in so many other relating to rimfire. As suggested, it's possible to dig up many examples of Eley ammo performing well at long distances. No doubt those shooters would say the same about their success shooting .22LR at distance as some would say of Lapua. And there's the rub: shooters will advocate for what works for them, empirical evidence based on observation. It doesn't admit contrary data because by its nature and from practical purposes it's can't be as convincing.

In any case, it's timely to note that many shooters report that currently Lapua produces more consistent ammo than Eley. But this changes over time.

Exactly and I appreciate this dialogue; yet another reason I truly believe this community is so awesome.

MB

 

[357Max]

No sir, sorry, but you're wrong. First, there's more data on this than you're currently aware of and that's on purpose. Second, the crown has nothing to do with the difference in why the 18" didn't work and the 22" and longer barrels do. Remember that we're working with a soft lead bullet here and centrifugal pressure is higher due to an increase in angular velocity. With that, there's something useful about the extra length that has nothing to do with full powder burn.

MB

@RAVAGE88 - I really appreciate your dialog in this forum. You and many other manufacturers direct involvement here are what make this place great.

Shot a CF PRS match today so I'm suffering from RWS (rimefire withdrawal syndrome).

I dipped my toe in the 22 waters with a B14R and now I'm hooked. Definitely plan on a purchasing a Vudoo in the near future.

My best 100y 6 x 5 avg to date has been with Eley Tenex. Granted I tried 4 lots, 2 shot well & 2 didn't.
In another thread I flat out asked the question "will the flat nose on the Tenex put me at a disadvantage when targets stretch out to 250y".
Crickets was the answer.

Having read this thread all the way through I think I got my answer and then some.
I already suspected the flat nose would hurt performance, but I will test this next weekend shooting 6x5's @100/200/300 using my best lot of SK long range (.683 moa avg @100) vs Tenex (.574 moa avg @100). It will be interesting to see if the SK catches or surpasses the Tenex @200 -300y.
The only way that can happen is if the flat nose causes ballistic fuckery farther down range.

My thoughts on the Lapua vs Eley:
It kinda seems like Eley new that the full .172 bc was unrealized in the 16t and just clipped the nose maybe for more consistency at the short ranges it's intended for. I strongly suspect that you wont realize the same bc gain from a fast twist with the Eley flat nose offerings?

In reference to your quoted post & just for fun I'm going to take a stab at the reason the 9T 22" shoots & the 18" doesn't.
18" is pretty dam close to max velocity so that would mean the bullet is getting released @ peak centrifugal velocity as well as MV (not ideal in my mind). Whereas the 22" barrel allows the bullet the fully obturate to the bore through peak centrifugal velocity & the last 4" deceleration allows it to stabilize/self center before release.

If the above is on the right track then it leads to another question. Would you need additional length for HV ammo to stabilize in the 9T?

Another thought is that it might be time to consider how soft the lead is in these match bullets i.e. fast twist match could maybe use a slightly harder lead?

 

[Gleedus]

Having done a lot of 200 yard ammo testing (only with 1-16) I would have to say that you can run into bad lots of ammo. But typically a given ammo at simular velocitys shoot the same at long range.
The Eley Tenex and Match have never been the best for me but often are a more uniform group distribution.
Eley contact and force have been my best followed very closely by SK Rifle Match and Long Range.
Lapua for some reason is simular to the Eley Tenex, Match in my Rifle.
The best group in the 50 at 200 is currently with Eley Match.
I bring this up just to remind us all that our rifle and its preferences are what matter. Not what buddys rifle shoots best.

@RAVAGE88 how have you found the 1-9 for fliers/ group consistency? The whole fast twist thing makes perfect sense as mathematically 1-16 is barely fully stabilized. 1-12 would look about right but 1-9 would be spun excessively which if we have a imperfect projectile should cause a flier.

 

[RAVAGE88]

I’m pasting here what I posted on Instagram (@vudoo_labs) about our testing of the fast twist barrels. This is preliminary info, will post data sheets when I get home.


Ok, more on todays fast twist testing, but I have to first shout out a HUGE thank you to Buford and Miss Cindy at @booneballistics. The facility is incredible, the capabilities and knowledge base is impressive, and it’s all closely rivaled by the hospitality and Miss Cindy’s sandwich making spread.

All total, we shot 12 tests today and three of the platforms were V-22 based rifles. One 16 twist Vudoo/Ace barrel measuring 20” in length and two nine twist barrels; one being a @bartleinbarrelsinc and the other a Vudoo/Ace. Both nine twist barrels are finished at 22”. The other barrels were from my buddies at @lotharwalther_usa and included nine, 10, 12 and 16 twist. I won’t speak to the Lothar results, as that is for them to do, but I can easily say that we had an incredible day validating the merits of spinning the @lapua_ammunition 40 grain lead bullet much faster than the standard one turn in 16 inches. All tests were shot at 100 yards.

For the @vudoogunworks rifles, we set a baseline with the new Three60 three lug and the Vudoo/Ace 16 twist. All recorded ballistic coefficient data is based on the G7 drag function, but the Oehler system makes it easy to select and display other drag functions. All ammunition was Center X and we averaged 1084 fps from the Vudoo/Ace 16 twist with a G7 of .0721.

Where it became really exciting was shooting the two Vudoo nine twist rifles across the Oehler and recording the results while simultaneously watching five shot groups through the spotting scope. The Vudoo/Ace nine twist barrel showed an average velocity of 1094 fps with average BC of .0742. The Bartlein nine twist showed an average velocity of 1093 fps with average BC of .0740. Pretty incredible, especially while watching the repeatability in the wind at 100 yards.

I’ll post up actual data sheets soon but I know there are many waiting to hear how the testing went, so the info I’m sharing now is directly off the summary sheets generated by the Oehler system. All-in-all, the testing was a complete success and without a single doubt, validates the Lab findings that started four years ago. @foundation_stocks @zerocompromiseoptic @mannersstocks @bulletpro150 @drengr.srl @timneytriggersusa @btindllc @area419official #defti #wordsmatter #toldyaso

More to follow….

MB

 

[Rimdenter]

Ain't nothing better then improving the BC. of the same bullet ! wait a minute how'd he do dat?

 

[RAVAGE88]

Ain't nothing better then improving the BC. of the same bullet ! wait a minute how'd he do dat?

Dude, it was incredible to watch it unfold, and this is after watching it happen for a few years now. Higher velocity and BC out of a 22” barrel with corresponding results at the target. I’m still pouring over the data, but there’s also continued validation of what we’ve seen happen to velocities out of longer 16 twist barrels.

MB

 

[Gleedus]

Dude, it was incredible to watch it unfold, and this is after watching it happen for a few years now. Higher velocity and BC out of a 22” barrel with corresponding results at the target. I’m still pouring over the data, but there’s also continued validation of what we’ve seen happen to velocities out of longer 16 twist barrels.

MB

In other words. Long barrels dont hurt velocity in a bolt gun like people often think.

 

[RAVAGE88]

In other words. Long barrels dont hurt velocity in a bolt gun like people often think.

Actually, longer barrels do lower velocities out of a 16 twist barrel. There’s also something relevant to rifling convention that equates to measurable performance.

MB

 

[JBoomhauer]

Thanks MB! All very interesting stuff.

 

[Gleedus]

Actually, longer barrels do lower velocities out of a 16 twist barrel. There’s also something relevant to rifling convention that equates to measurable performance.

MB

Interesting most guys I know with fast twist have lost velocity. But thats not a 1-9. Bore dimensions would make a difference too. Which is my second question. Are you running a tighter bore and "squeezing" the bullet more with a 1-9 creating a smaller diameter thats also helps increase the BC?

 

[RAVAGE88]

Interesting most guys I know with fast twist have lost velocity. But thats not a 1-9. Bore dimensions would make a difference too. Which is my second question. Are you running a tighter bore and "squeezing" the bullet more with a 1-9 creating a smaller diameter thats also helps increase the BC?

No sir, tight bore rimfire barrels do the opposite and slow the bullet down and I stopped using tight bore barrels for 22LR a number of years ago. So, let’s talk about why we hear mixed results about using fast twist over standard twist.

First, when one increases pressure on the bullet (via higher angular velocity), certain things have to be done to either make this pressure work for you, or lower the amount of pressure while still spinning the bullet faster. One does this by paying close attention to details and not failing to remember that just because the twist rate is faster that all things in rimfire world will suddenly be better. The environment for the bullet is changing drastically and this has to be properly addressed.

Second, the quality of the ammo becomes more critical. After seeing the data differently yesterday than I’ve been able to see it, the theory now is that powder burn is more efficient. But again, bore convention here is critical to what this really means. So, there’s a lot more to be discovered on this particular topic.

Overall, the importance of the rifle and ammo working as a system is even more critical with the faster twist barrel. The bottom line is, when I‘m told that “we didn’t have good results” or “we’ve not seen good results,” I’m immediately skeptical and convinced that something very important to good performance was missed. AND/OR, ones data isn’t being properly collected, interpreted or an inability to actually collect measurable data.

MB

 

[Gleedus]

No sir, tight bore rimfire barrels do the opposite and slow the bullet down and I stopped using tight bore barrels for 22LR a number of years ago. So, let’s talk about why we hear mixed results about using fast twist over standard twist.

First, when one increases pressure on the bullet (via higher angular velocity), certain things have to be done to either make this pressure work for you, or lower the amount of pressure while still spinning the bullet faster. One does this by paying close attention to details and not failing to remember that just because the twist rate is faster that all things in rimfire world will suddenly be better. The environment for the bullet is changing drastically and this has to be properly addressed.

Second, the quality of the ammo becomes more critical. After seeing the data differently yesterday than I’ve been able to see it, the theory now is that powder burn is more efficient. But again, bore convention here is critical to what this really means. So, there’s a lot more to be discovered on this particular topic.

Overall, the importance of the rifle and ammo working as a system is even more critical with the faster twist barrel. The bottom line is, when I‘m told that “we didn’t have good results” or “we’ve not seen good results,” I’m immediately skeptical and convinced that something very important to good performance was missed. AND/OR, ones data isn’t being properly collected, interpreted or an inability to actually collect measurable data.

MB

Thanks Mike keep sharing. I'm a "couple" years behind in experience. I do my own testing. So many rules of thumb I've seen fail.... now I question everything. Even you lol! Consistency and repeatability is important.

I have to very much agree with interpreting data.

 

[RAVAGE88]

Thanks Mike keep sharing. I'm a "couple" years behind in experience. I do my own testing. So many rules of thumb I've seen fail.... now I question everything. Even you lol! Consistency and repeatability is important.

I have to very much agree with interpreting data.

By all means, Dude, keep the questions coming.

MB

 

[Gleedus]

By all means, Dude, keep the questions coming.

MB

With the fast twist do you find that the higher quality ammo is required for consistent long range groups? Are the 1-16 more forgiving of imperfect bullets? The 1-9 better on average but if you have a bad bullet it has a flier?