Krieger gain twist barrels and long range shooting

[Rich De]

While I shoot with Mike Davis and Larry Isenhower and know of the gain twists, I also know that some record shooting has also occurred with straight 8.5 twists. I don't think the gain twist is necessarily the "best thing since sliced bread?" They may turn out to be so, and obviously a post like this can sell a lot of barrels but it does not mean you will shoot a record because of it I had discussed this with Dave Tooley (who posted above) and the reason he is using it in the bigger calibers to reduce torque in sniper type rifles. I don't think he is necessarily sold on it for the 6mm. Mike Davis has shot 8.5 Brux barrels very well. There was a time when everyone had to have his barrel Cryo'ed? Now, you don't hear all that much about it? Kind of like the transition from the .222 to the PPC. It didn't happen over night. I don't think the gain twist will hurt accuracy, just am not sure its magic
Rich De

 

[JD Mock]

I will be testing a 8.25-7.75 Bartlein

I am working on an article which will feature a Bartlein .236 X .243 gain twist that is 8.25 to 7.75. I will test it in a BAT 6mm Dasher. The rifle has a straight 8 twist on it right now. I plan to use several bullets from 105 to 108 grains, and perhaps a few 115's. James

 

[Rich De]

JD........thats the way to help prove a point. Side by side comparrison. While not fool proof, it does lend more creedence to the decision as to which might be more accurate. Particularly if a number of shooters did the same type of test. I hope you will have the results written up in PS.
Rich De

 

[JD Mock]

It will be in PS

Although it may be several months until it is published, I will write the results. I am new to 600 yard shooting, but will use the new Bartlein GT in some matches. The gain twist barrels have done so well in shortrange BR, I thought that it would be appropriate to try one with the fast twist (8.25 to 7.75). I am now waiting for the barrel, but I will begin testing with the 8-twist that is on the rifle now.

Rich, as a world record holder, could you suggest some good 6mm Dasher loads? Thanks, James Mock

 

[Rich De]

JD.........thats "former" Sorry on the Dasher loads James. I have not shot the Dasher. The 6mmBR and a 6 x 44 imp. are the only two 6mm's I have shot in 600 yard competition. This BRX will be new to me. I have a Brux 8.5 twist sitting in my shop awaiting some attention on my part. So far, I have only chambered my XP-100 LR pistol with a used (600 rounds) 8.5 twist Border barrel, 15" of fat barrel. I have two main purposes for this pistol: Fireforming brass for the rifle and for use at the Hickory Groundhog/Egg shoot. I have been shooting it with a 1-14" barrel in 6mmbr but wanted to shoot a heavier bullet for the 500 yard stage. This BRX gave me the perfect excuse to do the chambering. I have already fireformed 100 pc. of brass and shot as good as 1/2" five shot at 300 yd. while doing so. Hopefully the Brux will perform even better attached to my Viper actioned light gun.
Rich De

 

[Marine sniper]

Sorry for the dumb question; but what are the expected advantages of a gain twist barrel?

 

[alinwa]

Sorry for the dumb question; but what are the expected advantages of a gain twist barrel?

I'll try to get the ball rolling

Here are some of the things it might:

#1- a gain twist might combat core slippage. When pushing big bullets fast it's possible that winding the bullet up slower may keep it in better shape. Max pressure occurs in the first inches into the lands and some will say that keeping rotational stress down at this point could help something.

#2- it changes barrel vibration pattern..... adds a component to the vibration mix which may be beneficial.

#3- keeps the rifling "cutting or biting a new surface" all the time. I'm not sure what the benefit could be although I've heard folks quote better gas seal and others are convinced that the effect "evens out the pressure curve." I can't see any difference between this and the fact that the bullet is accelerating but hey......

#4- it's cool...... this I'm with. I've got one, will try more.

#5- "it acts like a choke"...... I've got no freakin' idea'r what this means but I've heard it a bunch.

There, now someone else can opine

al

 

[Lynn]

Alinwa
It would be nice to send one of these barrels to Henry Childs to see how they tear up or don't tear up bullets.
I have yet to hear any reports of bullet failure issues but something about the twist changing and its affect of widening the lands width on a bullet comes to mind.
If someone starts out with a real slow twist and goes to a real fast twist how much of the bullets bearing surface would get re-shaped as or widened/narrowed as it travels down that hot bore kind of a thing.
Just thinking out loud here.
Waterboy

 

[a6mmbrman]

Gain Twist

I'll try to get the ball rolling

Here are some of the things it might:

#1- a gain twist might combat core slippage. When pushing big bullets fast it's possible that winding the bullet up slower may keep it in better shape. Max pressure occurs in the first inches into the lands and some will say that keeping rotational stress down at this point could help something.

#2- it changes barrel vibration pattern..... adds a component to the vibration mix which may be beneficial.

#3- keeps the rifling "cutting or biting a new surface" all the time. I'm not sure what the benefit could be although I've heard folks quote better gas seal and others are convinced that the effect "evens out the pressure curve." I can't see any difference between this and the fact that the bullet is accelerating but hey......

#4- it's cool...... this I'm with. I've got one, will try more.

#5- "it acts like a choke"...... I've got no freakin' idea'r what this means but I've heard it a bunch.

There, now someone else can opine

al

Al pretty much sums it up. As far as (choke) is concerned you can have the barrel made with up to .0003" from breech to muzzle. Krieger barrels are made with .0001" as a standard. I prefer a little extra (choke) in mine.

Rich is right they are not magic, but if anyone knows where there are any magic barrels please let me know...

Mike Davis

 

[Greg Culpepper]

I've been following this discussion with a lot of interest since I bought a Bat DS with a gain twist Krieger from Mike late last year. It's my first 6BRX, first Bat, first gain twist, first Davis barrel work and was stocked by Lambert in an unusual wood/carbon fiber design of his creation.

Well, I shot it for the first time this past week and it shoots good.

Mike gave me gave me fifty fire formed cases with the gun and instructions that a gain twist will like a little more powder than a conventional barrel. His last test load was 34 grains of Varget (He had put 135 bullets down the barrel) so I put that under the same SMKs I've been getting good results with in the 8 twist Krieger 6BR and went to Hickory.

I missed the 500 elevation (and condition) but the gun performed beautifully. Keep in mind when looking at the groups that you hold off shot to shot to get back to the middle of the ring . Group size is not a consideration. Staying away from the edge is. I don't think anyone can see bullet holes in the black at 500 so if you can't see the result of your first shot you can either bracket or hold on the middle like I did. There's only 0.300" elevation dispersion in the 500 yd group. Pretty good for the first time out!

I don't know if gain twist is magic but it sure didn't hurt anything that I can tell. I'm looking forward to more experience with this rig.

Well done Mike and Butch. Thanks.

Greg