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May 17, 2010
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So I am just minding my own business on the other gun site when this is linked to
Brownell's Gunsmith Tech Corner Link
Its a chart of "best choice" for twist rates of gun barrels. I really wish they had done more explaination.. but it is a neat start. I just can't recall the twist rate for the 15-2.. for some reason I want to say it was expressed as 1/16 w/7 lands.. but I could be all wrong on that.
The point is.. now how cool would it be to have a barrel just for my .38spl wadcutters for ICORE shooting which only needs to be:
Ammunition must produce a minimum power factor of 120000. The power factor equals bullet weight in grains multiplied by velocity in feet per second. All competitors may be tested for minimum power factor at any ICORE match. Six rounds will be collected from each competitor at random during the match and at least one of those six must equal or exceed a 120000 power factor when shot over a chronograph through the competitor’s firearm. A seventh round may be collected and weighed, to accurately determine bullet weight. "FAILING TO MAKE CHRONO" will result in 360 seconds being added to a competitor's score. A competitor, using a revolver chambered in .38 Special and/or .357 Magnum and using factory new UMC 158 grain, Remington 158 grain, Blazer 158 grain, or Federal American Eagle 158 grain ammo, may compete without regard to power factor.
I generally shoot 158grain which I figure only needs to be going about 760FPS to meet this spec. Thats a fairly typical load. So using the chart I only need a 14" twist.
Now when shooting a .357 say at knock down plates I want to power up to say 1250fps. They are showing a whopping 18" twist rate! This leaves nice wide open place for custom barrels designed for the bullet weight and velocity to be used. And a 125grain .357 can be 1400 up to 1600fps!
What say Eric? something to think about… not just making replacement barrels… but making barrels purpose built to suit the type shooting.
Soap Box, Ballot Box, Ammo Box
in that order.
4 Monson Model 15's
1 Palmer FB 15
1 Rossi 357 Model 92 (lever)
1 CZ 75B
Range Officer
Range Officers
Dans Club
February 28, 2009
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That is a really cool idea. It could really maximize the flexibility of the DW interchangable barrel system. In an article that Tony Spoti wrote about the 414 SuperMag, he stated that the standard twist provided by DW was 1:18. He asked them to make a barrel in 1:14 (which matches the chart you reference) and got better performance.
Really cool.
-Mike
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Range Officers
May 2, 2009
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Directly from the former VP of operations at DW...
"The standard twist ( memory) was 1 in 16''.Made in house, broached on a pull broach that was around when dinosaurs were on there way out.(i personally pulled thousands of then ) Anyway the rifling (broach) had cutting buttons that were extremely difficult to sharpen.We sharpened them in house as the technology was on the verge of outdated. The cost of new was staggering and at the time the current owner was putting all profits in his pockets returning only enough to keep the doors open. Thus the beginning of the demise of D.W. A. Back to twist. The factory bbls were doing the job ,however there was much room for improvement. The Action Cup shooters in Europe started the want for a faster twist bbl improve accuracy. We started sending our gun drilled bbls out of house to be rifle boared. Changed- the twist and finish product was superior. Lands & GROOVES were impressive, faster spinning bullet, bingo.The cost kept them limited though 1 in 12-'' twist was the answer. One rev.in 12 inches. I could go on 4 ever so i hope you got the answer"
SHOOT
May 17, 2010
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hehe Shoot you rather prove my point....
EWK can differentiat his barrels (not even thining shrouds here) by offering variable twist rate barrels ( at least for the 15-2) since it handles a wide range of velocities. This means the gun should be even MORE accurate for the now fragmented revolver competitions.
1/12 ICORE
1/14 38 spl standard
1/16 general use
1/18 .357 high vel use
Moving to the other calibers.. so Shoot was that ALL calibers/models stuck with a 1/16? It would seem that a .357 max might benefit from 1/18 even more so than a mag.
Most of this gets beyond me pretty quick... the point being differinatation adds value to EWK offerings.
PS: if you do this eric you will need to mark the barrel as to twist rate 
Soap Box, Ballot Box, Ammo Box
in that order.
4 Monson Model 15's
1 Palmer FB 15
1 Rossi 357 Model 92 (lever)
1 CZ 75B
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Range Officer
Range Officers
May 2, 2009
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I believe this was the setup for the 357 barrels as that was their primary production model; although they may have used the same setup for 38 spcl. I have a few of the fast twist barrels, and it is readily apparent when you look down the barrels side by side.
SHOOT
October 13, 2009
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That's what the test barrels are (1:12 twist) based on shoot's investigation. 
But yes, a selection of twists wouldn't be a problem provided they are in reason. Like 14.255 twist, 14.256 twist, etc, is gonna be a problem for me. 
And I agree, marking would have to be in order to tell them apart!
Eric
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Moderators
January 24, 2009
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SHOOTIST357 said:
I believe this was the setup for the 357 barrels as that was their primary production model; although they may have used the same setup for 38 spcl. I have a few of the fast twist barrels, and it is readily apparent when you look down the barrels side by side.
Shoot, have you shot any of your fast twist barrels? Just wondering how they may have performed...
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Moderators
Dans Club
February 22, 2009
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"And I agree, marking would have to be in order to tell them apart!"
Just use astrerisks similar to the old browning shotguns, ie:
* = 12
**= 14
***= 16
etc...
Technically, the glass is always full; half liquid, half air....
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