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View Full Version : Bartlein gain twist barrels-what twist?



gabe ledesma
06-07-2013, 08:48 PM
I am going to order a couple of bartlein gain twist barrels just to try them out. All of my benchrest shooting has ben with 6mm 237 bore dia. 14 or 13 1/5 twist barrels. What is a good gain twist that has ben working for you out ther that have used gain twist barrels?. I was thinking maybe 13.9 to 13.8 ,or is there a better twist that is working better on your guns? this will be on a PPC light bench gun

Eddie Harren
06-08-2013, 05:07 AM
You have a PM.

abintx
06-08-2013, 11:18 AM
I am going to order a couple of bartlein gain twist barrels just to try them out. All of my benchrest shooting has been with 6mm 237 bore dia. 14 or 13 1/5 twist barrels. What is a good gain twist that has been working for you out there that have used gain twist barrels?. I was thinking maybe 13.9 to 13.8 ,or is there a better twist that is working better on your guns? this will be on a PPC light bench gun

Bruno's has the Kreiger in three twists: 14.2 to 13.4, 14.6 to 13.8, and 15 to 14.2. I've used the 14.2 to 13.4 and couldn't say one way or the other if it made much difference.

I read somewhere that Tony Boyer had used the 15 to 14.2 and shot well with it, but that man can shoot well with any twist or combination of twists.

I suggest you start with the 14.2 to 13.4 and then work your way through the others to see what works for you and if it makes any difference at all. The theory certainly sounds great. Good luck. :)

Jefferson
06-08-2013, 11:46 AM
The Canadian barrel maker Ron Smith as I recall thinks that unless you do a larger window the increase is not sufficient to make a difference,

I have barrels from Ron that go from about 15 down to 8 for 6BR and from 13 to 7.5 for a .223 both for F-class, I saw no need for a gain twist in 6PPC, no need as the gyroscopic effect is minimal in that distance with a minimal twist rate increase, (do the math)

A BETTER APPROACH is to get a proper twist rate to begin with (remember when the 13.5 twist and 13 twist barrels came out for shortr range BR, and now they are accepted)

and in the past some barrel makers were NOT HOLDING THE TWIST RATE TO THOSE ADVERTISED but could vary about .3 to .4 in a 14 twist (so up to 14.3 and no wonder it would not stabilize bullets)

D A made a machine to test proper twist rates )and showed them the error of their ways) and if Kreiger would talk they may admit asome of thier barrels would noit make spec when sent out, they have now fixed the problem a couple of years ago,

there is more but it serves no useful purpose for this forum, all that would happen is for nay sayers to come on to poo poo the idea,

have fun but it is not worth the effort for 6PPC (but if it makes you feel good and you think it works , GREAT)

in the past some well known barrel makers were giving you gain and non gain twist barrels as they were not done properly by their staff,


Jefferson

Boyd Allen
06-08-2013, 12:43 PM
When I asked a friend, who has made a couple of WBC teams, about his experiences with gain twist barrels for 6PPC, I definitely got the impression that he was not at all sold on them having any advantage. If you think about it, the rate of rotation of a bullet increases (gains) as it accelerates down the barrel, even with a constant twist rate. I think that a more interesting question about barrel accuracy potential comes from slugging barrels, to feel minor differences in how tight they are at different places down their bores. A couple of fellows that I know have taken a look at this, with interesting results. As far as twist rate selection goes, I am sure that you already know that bullet length, shape (whether it has a BT) and air density have effects on how much twist is required to achieve a given level of stability. One thing that has recently happened that speaks to this, is that Berger chose .790 jackets for their new Column design. My guess is that they did so because that length is a better match with 14 twist, under a variety of conditions, than .825, a different way to get to the same place that Bruno got to by using a 13.5 twist for his longer BT bullet. My late friend Del Bishop made a number of bullets on the shorter jackets. This was not an accident. He did a lot of testing with his rail gun. For some of us, these differences tend to get lost in the wind, but for you, I think that these are good things to consider.

Added later:
Back in the day when cut barrels did not dominate short range benchrest and button barrels ruled, they were known to have variable twist rates going down their length. This led to the development of machines to measure this particular characteristic, and there was one company that you could sent a barrel to to get this, and bore dimensions, measured and charted. Given that twist rate wandered a little within the length of a bore, it was thought that the best barrels would have a slight gain at the muzzle, as well as a little choke. Lapping for button barrels was/is for dimension as well as finish. Cut barrels, on the other hand, by the nature of the process by which they are made, do not have a wandering twist rate issue , and Krieger will tell you that they only lap for finish, not dimension, so the issues that were/are important for buttoned barrels, are not as likely to cause problems for cut barrels. This is not to say that buttoned barrels are inferior, just that the process by which they are made creates different issues that need to be monitored and controlled.

mturner
06-08-2013, 02:00 PM
Listen to Boyd. I have always felt like the only thing to be gained by a gain twist barrel was twist, not accuracy. The rpm of the bullet is accelerated at the same rate as the velocity, and both peek at the same time when the bullet reaches the end of the barrel. I have heard of super fast twist barrels being too fast and wanting to strip the jacket. I don't have any proof that this is a factual problem. I doubt it is, but if so, a twist from 12" to 7" might be a good thing. There is a definite problem that I see with gain twist. The grooves that are engraved or ironed into the bullet would have to cause greater bullet distortion than a uniform twist rate, because they have to become wider as the twist changes. Just like threading a course bolt into a fine thread nut would cause thread distortion. Off course this distortion is minimized by the fact that gain twist barrels have very little gain, but wouldn't minimum gain defeat the purpose of any real gain anyway? Benchrest shooters run the slowest twist they feel comfortable with in the first place, so why would we feel like this is putting the bullet through too much stress?

Michael

abintx
06-08-2013, 03:03 PM
IMHO, regardless of whether you're shooting with a constant twist barrel or a gain twist barrel, as soon as the bullet exits the bore, it's at the mercy of the elements, especially the wind.

The greatest emphasis should be on learning to shoot over a good set of wind flags and trying to memorize what different wind conditions do to the point of impact and when to pull the trigger.

If you watch the great shooters they wait for their condition of choice and then get as many rounds down range as possible while that condition holds [regardless of barrel twist]. :)

Boyd Allen
06-08-2013, 04:08 PM
Gabe is a better than fair shooter. I just think that like all of us, when he is shopping for a new barrel, he doesn't want to overlook any advantage.

Charles E
06-08-2013, 06:18 PM
Gabe is a better than fair shooter. I just think that like all of us, when he is shopping for a new barrel, he doesn't want to overlook any advantage.
Since we still don't know what -- or what company, for that matter -- makes a better barrel, the best strategy is to buy as many as you can afford, have them chambered, and test.

IBS Shooter of the Year in 1,000 yard BR proved that last year. Well done! Moreover, it needed to be done. In the last quarter of the season, the person who started with 30 (or so) barrels out-pointed the person who started with only 20. It was neck & neck up to then, but S_____ L____, who said he got 3 great barrels out of the 20, didn't have a superior barrel to finish off the race.

James M.
06-08-2013, 06:37 PM
One of the best barrels that I have owned is a Bartlein Gain Twist. It is chambered for the 6mmDasher and features a 8.25 to 7.75 inch twist. It handles 105-108 VLD bullets very well. James

skeetlee
06-08-2013, 06:52 PM
Doesnt Gene Buckeys shoot a lot of gain twist barrels? Seems i read that somewhere. If i were to ever buy a gain twist is would be Bartlein for sure.
Also seems to me that i read, or was told that the gain acts in a similar way as a slight choke???? I dont know!!! Lee

gabe ledesma
06-09-2013, 01:03 AM
One of the the things that i trully like about this sport is trying out new gadgets ,weather it be stocks actions or Barrels. When i started in this sport back in 2000 i thought that a 6br was the way 2go. I used a 6br 100short for a couple of years untel i swiched to the PPc, not that there is anything wrong with the 6br short but bumpng the shoulder back and all of the extra trimming was a real pain in the butt. Also when i started benchrest shooting my first gun was a sleaved 700 action. It was a good gun but when i sold it i only got about half of what i put into it. all of my actions ar custom actions now. Yes i am allways looking for an edge in this sport weather its barrels actions stocks or bullets. Shooting benchrest is one of the best decisions i have made in my life,i have gotten to know some great people in this sport, people like ,walt berger and his wife Eunice Berger who is no longer with us. Don gentner geary ocock and our president dennis thornburry, and of cours my good friend brother Boyd Allen just to mention a few. thanks all for all the replys. your friend Gabe

martin zuck
06-09-2013, 09:49 PM
Back in the late fifties and early sixties some of us played around with barrels made by Johnson. They referred to these barrels as "progressive twist". Some of them shot as good as straight twist barrels but not any better. Fifty years later history repeats its self!

TSI243
06-14-2013, 12:12 AM
Doesnt Gene Buckeys shoot a lot of gain twist barrels? Seems i read that somewhere. If i were to ever buy a gain twist is would be Bartlein for sure.
Also seems to me that i read, or was told that the gain acts in a similar way as a slight choke???? I dont know!!! Lee

I do shoot gain twist Bartlein exclusively --- what I shoot is a 13.850 to 13.750 gain ---and I have been shooting them for the last 5 years

These barrels have won the last two world championships, two of the last three Super Shoots, The IBS nationals, and the NBRSA nationals along with other local and regional shoots.

While gain twist may not be helpful, --- I'm sure not changing what I'm using --- seems to work well for me

Gene Bukys

Boyd Allen
06-14-2013, 01:58 AM
Charles, did you get that?

Thanks Gene.

Charles E
06-14-2013, 10:34 PM
Charles, did you get that?

you mean


While gain twist may not be helpful, --- I'm sure not changing what I'm using --- seems to work well for me

Sounds good to me. What's your point?

Or are you saying Mr. Bukys only buys (wins, acquires) one barrel & uses it for the next 1500 rounds?

Phill Smyth
06-24-2013, 08:56 AM
Back in the late fifties and early sixties some of us played around with barrels made by Johnson. They referred to these barrels as "progressive twist". Some of them shot as good as straight twist barrels but not any better. Fifty years later history repeats its self!

Ga’day Guys, when I saw the note on the Johnson barrels, I had to ask, I have a Winchester 52 22 LR with an Eric Johnson and it shoot great. I am not sure how many went through it before I got it, being it was on a stock Win 52 B.
My Question is how good were his barrels at the time?, Top of the crop or ?.
I have been interested in BR for some time and shot some Rim a number of years back. Starting to get back into it, with older Hall 6mmppc, to get to know the ropes and tune the skills needed before I get a competitive LV HV kit. I just do not know if I can afford to be competitive, due to the costs, barrels, projectiles, and the time you have to wait to get many of the quality components to build competitive rifles and shoot, compared to Rimfire & Air BR and Rifle Metallic silhouette I shoot. I like to buy or build quality and accuracy once and look after it, so I have confidence in my equipment
Why is it that there is such a long wait for stocks, barrels, actions and other components coming out of the USA? Just a Farley or SAB rest takes forever. There must be a growing number of BR shooter in the states compared to Australia and the rest of the world. I thought numbers were dropping not increasing.
The people in the Benchrest fraternity here in Australia are a great group, like most in the shooting sports. I am looking forward to seeing some of you guys at the Worlds in Australia.
I enjoy reading the lifetime of knowledge you guys have, and how freely you share it to improve the sport and the enjoyment of those competing. Regards Phill Smyth

Ian_Owen
06-28-2013, 04:57 AM
Ga’day Guys, when I saw the note on the Johnson barrels, I had to ask, I have a Winchester 52 22 LR with an Eric Johnson and it shoot great. I am not sure how many went through it before I got it, being it was on a stock Win 52 B.
My Question is how good were his barrels at the time?, Top of the crop or ?.
I have been interested in BR for some time and shot some Rim a number of years back. Starting to get back into it, with older Hall 6mmppc, to get to know the ropes and tune the skills needed before I get a competitive LV HV kit. I just do not know if I can afford to be competitive, due to the costs, barrels, projectiles, and the time you have to wait to get many of the quality components to build competitive rifles and shoot, compared to Rimfire & Air BR and Rifle Metallic silhouette I shoot. I like to buy or build quality and accuracy once and look after it, so I have confidence in my equipment
Why is it that there is such a long wait for stocks, barrels, actions and other components coming out of the USA? Just a Farley or SAB rest takes forever. There must be a growing number of BR shooter in the states compared to Australia and the rest of the world. I thought numbers were dropping not increasing.
The people in the Benchrest fraternity here in Australia are a great group, like most in the shooting sports. I am looking forward to seeing some of you guys at the Worlds in Australia.
I enjoy reading the lifetime of knowledge you guys have, and how freely you share it to improve the sport and the enjoyment of those competing. Regards Phill Smyth

Phill I can't answer your other question but sure hope someone can answer the bit I highlighted in your post...........why are stocks, actions, barrels, bullets, Farley rests etc so hard to come by if the number of Benchrest shooters is declining??.......Ian

gabe ledesma
06-30-2013, 06:19 PM
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alinwa
07-02-2013, 09:54 PM
I don't know what the other guys answered (deleted) but IMO the answer is right here....... the internet.

BR shooters may or may not be in the decline but in any case they're NOT the main buyers IMO. BR sets the standards, innovates and culls the wheat from the chaff but the markets are driven by buyers and thanks to the innernet these buyers are better informed than ever before.

Or at least excited enough to buy the good stuff.

Al

B J Atkinson
07-22-2013, 06:42 AM
Doesnt Gene Buckeys shoot a lot of gain twist barrels? Seems i read that somewhere. If i were to ever buy a gain twist is would be Bartlein for sure.
Also seems to me that i read, or was told that the gain acts in a similar way as a slight choke???? I dont know!!! Lee

I was shooting next to Gene at the WBC in South Africa. I noticed that he had a 15 to 14.2 Bartlien barrel, so I ordered one when I got back to Australia. Took about 18 months to get here, but has won me the 200 yard agg in two of the biggest matches over here so far. Yeah....I reckon they are alright.