What is Best Twist & Barrel Length for 40 VMAX When Rebarreling to .204 Ruger ?

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gunsbam45

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I am going to continue to hunt for a Kimber Montana in .204 or one in .223 to rebarrel to .204 for now, but if no luck before too long will be buying a short action Montana and a Pro Varmint in .223 or .204 to have Mark Penrod make me a Montana in .204 from. Mark asked what twist I wanted to go with on the barrel, and I told him I honestly wasn't sure, but I'm hearing purty much across the board 1 in 12 is borderline and some will shoot 40 VMAX good and others not. He said that most guys going with .204 are saying 1 in 11. I have had VERY good luck with the factory 40 grain Hornady VMAX ammo performance wise, and see no need to do any loading for my purposes, at least at this point, but I'm going to do some testing with that load in my 700 Sporter soon on paper and over the chrono to see what I see. Regardless of whether I stick with factory ammo or end up buying 40 VMAX and reloading, what say Y'ALL on best twist to go with? I am not asking to second guess Mark, he just didn't seem like he was really giving an opinion, but simply passing on what others were wanting, and leaving it up to me to decide. Well, I flat don't know, so hopefully you guys do. Also, I've heard 23" is where you get optimum performance in this caliber, but again, I do not KNOW. I want to get the rifle as light as possible, but with Maximum velocity potential.
 
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The slowest I would go is 1/11, my TC 204r is 1/10. I ordered a 1/10 for my 20p. If your not threading/suppressing, I went 26" finish on my 17 rem. And glad I did the sporter wt barrel is light to carry and gets the most velocity from the cartridge. If top end velocity is not a concern, I would follow the advice from the Texas warehouse tests, 21.75" is the optimum accuracy length. I built 2 22-250 rifles at this finish length, both incredibly accurate.
 
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I have a T/C Venture Predator with a 1:10 stock twist. It shoots the 40 grain VMaxs well but it shoots the 32 grain VMaxs a bit better in all the loads I have tried so far. As others have stated 1:11 twist should be sufficient for all 40 grain bullets. A 1:10 twist will be fine as well but it is probably not necessary since most bullet manufacturers have abandoned bullets over 40 grains.

I recently read an article that showed a 23" barrel as having the highest velocity in 204 Ruger. Just saw a video showing the 26" barrel being significantly faster than a 22" with 32 and 40 grain bullets.
 
On twist I would go with an 11 that will cover 32 to 40. As for length I have had 20 24 and my buddy has a 26. I'm going to rebarel my 20 inch this year with a 26. His accuracy load is running 3950 with a 39 gr SBK.
 
I went back and found that article on the visit to Virgil from the warehouse. That's a good read. I had forgotten about that 21.75" barrel length completely. I've had good luck with the factory 40 VMAX ammo in my 24" factory 700, but never tested it on paper other than at initial sight in when new. I'll be running factory Hornady 40 VMAX ammo on paper and over chrono next wind break we get just to see. It drops coyotes like they've ate a grenade with no hide damage. Now, red squirrels are another story, but I don't save the hides on them anyway.
 
Do you think the 11 twist will be more accurate with the 40 VMAX than the 10 twist? I will likely try the 39 Sierras eventually but doubt I'll ever have a reason to go any lighter than that.
 
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It's possible but I doubt it. As long as 1:11 fully stabilizes the bullet a slightly faster 1:10 twist will most likely make no difference. Bullet manufactures state a specific minimum twist or faster. I've never seen one state a maximum twist rate.
 
My first .204 had a 1:12 and it did fine with the 40’s so a 1:11 won’t have any problem. My 1:11 is only 18 inches and it will stabilize 32’s, 40’s and 45’s
 
I'll throw a different twist, pun intended, into this.
We're all aware of how the 17's and 20's kill Predators which many agree it's do to velocity and bullet size/design. But I think there is another reason that adds significantly to the equation. RPM.
I believe the faster RPM coupled with the velocity is the primary reason these calibers are so good at what they do.
Therefore, I would go with a 9 or 10T. But, if I was building a Fur saving Predator rifle I would put the 2 known fur calibers together and build a 17-204 and run 30gr. bullets.
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Go with Mark's suggestion on the 1-11 twist...that will do everything you need it to do...and will for sure stabilize the 40gr vmax.

Mark has done most all of my rifles and if he suggests something, then it is probably best to take his advice.
 
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An old BR axiom for best accuracy is to go with the slowest twist rate that will effectively stabilize the length of bullet that you plan to shoot. In this case a 12" twist is marginal in stabilizing the 40 grain VMax but an 11" twist effectively stabilizes it. Hence the 11" twist rate will likely give you the best overall results. A 10" twist barrel might show the same results in terms of accuracy, but that comes with no extra benefits unless you may want to shoot even longer bullets in your rifle at some point in time. Kind of like extra insurance for the future in case the situations change.

If it were my rifle, I would go 11" twist and not look back.

As for barrel length, I'd stick with 22" for maximum handiness. Longer barrels, like 26" for example, might give you a bit more velocity, but they are a PITA to handle in many hunting conditions and they generally don't deliver any significant additional velocity that can be utilized in any manner at normal hunting ranges.
 
Unless I am wrong and please correct me if so, I don't believe there are any .204 bullets over 40 grains still in production.
 
Originally Posted By: rkite Unless I am wrong and please correct me if so, I don't believe there are any .204 bullets over 40 grains still in production.



With the exception of a few custom bullet makers, you are correct, there aren't many options out there for heavier than 40gr in the 20 caliber bullet world.

Largely, one of the reasons Berger discontinued their 55 gainers was they just didn't sell a lot of them. No commercially available 20 cal comes with enough twist to shoot them and there just aren't enough of us fast twist 20 cal shooters out there to make it worth it for them to keep making their 55's on any kind of regular basis. It kinda takes a specialty built rifle to shoot those 55's.

With commercially available 40gr ammo for the 204 Ruger and the fact the 40's are kind of marginal out of a 12tw it is a little surprising they haven't gone to producing 204's with a 11tw from the factory.

When I had my 20-222 built I spec'd an 11tw so I could shoot up to the 40's with it.
 
On an interesting side note. If you run Berger Bullets twist rate stability calculator it shows the 40 grain bullets and 32 grain all copper bullets needing a minimum twist of 1:10 to be what they call "Comfortable Stability". This is if you enter less than 3000 feet of elevation above sea level.
 
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