6mmbr Barrel Twist Thoughts

[Shynloco]

Guys,
Looking for opinions based upon personal experiences. I have a Savage Model 12 Benchrest 1:8 which I use to strictly for 100 yds shooting. I also have found that using Barts 68 gr Ultras give me the tightest groups being pushed by VVN133. That after testing several other bullets and custom ones as well. The rifle now has nearly 4,000 down the tube and the groups are starting to open up. I've got two choices as she has a long barrel. 1. Have the barrel cut, rechambered and remounted or 2. Mount a new Kreiger with a 1:13.5 twist which I have read may work even better because of the distance I shoot plus the bullet I've selected. Question: Which do you think is my better choice for better accuracy. Thx

Alex

 

[82boy]

To start, every barrel has it own personality, (Regardless of make) and it may be you got a really good barrel from Savage. It is also possible that you could get a sour barrel from Krieger. (Not very likely.) You don't say what kind of accuracy your getting from this barrel, and what your expectations are as far as accuracy goes. Chances are that the Krieger barrel will out preform the Factory Savage barrel, it just has much more going for it. You may be surprised and find that a pre-fit available from many sources(Shilen, McGowan, Criterion, ETC) will preform as good as the Krieger, and possibly be more accurate that you desire for less money.

All in all what your doing presently is not a proper fit. The 1 in 8 twist barrel is designed to shoot heavier bullets, and is better suited for longer yardages. The bullets your shooting are designed for the yardage your shooting, but not to be used in a 1 in 8 twist barrel. 133 is a fast burning powder, and would be a good match with the lighter bullets, but it there may be a better suited powder for the case capacity of a BR, and the barrel length. Most people that shoot 133 use shorter barrels, (20 to 24 inches common, and very few out to 26 inches long.) and the factory length of your barrel is 29 inches. Most shooters that are shooting Bart ultra are shooting them in a 1 in 14 or faster twist such as a 1 in 13.5 or 13, but as mentioned it is not the preferred bullet in a 1 in 8. I have owned a few barrels and was hard pressed to tell a difference between a 1 in 14 and a 1 in 13.5.

You say you have over 4000 on the barrel, well I would state that this barrel has lived a very good life and doesn't owe you a thing. If you can have the re-chamber done cheap, then I would go for it, and see if the barrel comes back to life. Many who do re-chamber barrel would have done so much much sooner than what you have. You may find that erosion is so bad, that there is not enough material to cut the barrel off, and have the area big enough to place threads on it. Stating that savage barrel have a taper, and you might need to cut 6 or more inch's off the barrel chamber to get a fresh chamber. Having a bore scope and looking at the barrel would be a big help in determining if it is worthy of a re-chamber.

With that all said what your doing is very uncommon, and you may find that you can not repeat the results, with a new gun or barrel. Chances are that a aftermarket barrel will out preform the factory barrel. Chances are that the aftermarket barrel will last as long as the factory barrel. (Most don't push them that far.) Chances are that match the bullet and the powder to the right barrel parameters, will result in a better, more efficient, better shooting rig. But no one can make any guarantees, but the chances are very high that putting things right will pay off.

 

[big bad bill]

Alex,
82 boy is giving you good advice. I have a 6BR with a 14T 22inch Lilja 3gr and an 8T 27 inch Lilja 3gr. For your 100 yard distances, get the slow twist Kreiger or whatever brand barrel and you may be able to shoot nearly as well as with a 6PPC, mine does. Don't forget to try Berger column bullets.
Good shooting,
Bill

 

[Shynloco]

You don't say what kind of accuracy your getting from this barrel, and what your expectations are as far as accuracy goes.

All in all what your doing presently is not a proper fit. The 1 in 8 twist barrel is designed to shoot heavier bullets, and is better suited for longer yardages. The bullets your shooting are designed for the yardage your shooting, but not to be used in a 1 in 8 twist barrel. 133 is a fast burning powder, and would be a good match with the lighter bullets, but it there may be a better suited powder for the case capacity of a BR, and the barrel length. Most people that shoot 133 use shorter barrels, (20 to 24 inches common, and very few out to 26 inches long.) and the factory length of your barrel is 29 inches. Most shooters that are shooting Bart ultra are shooting them in a 1 in 14 or faster twist such as a 1 in 13.5 or 13, but as mentioned it is not the preferred bullet in a 1 in 8.

Having a bore scope and looking at the barrel would be a big help in determining if it is worthy of a re-chamber.

Chances are that a aftermarket barrel will out preform the factory barrel.

Thx Patrick! I do appreciate the comments, most of which have already been considered. Let me respond in the order Patrick's comment were presented. The accuracy this Savage has presented has been phenominal for an across the counter rifle. In the past it has consistently shoot in the 2's so long as I do my part @100 yds. My expectations are purely the best accuracy I can muster because I don't compete and have no expectations to do so. I am also aware that my rifle was designed for long distance shoot (600yd - 1K) and isn't supposed to shoot the light bullets. But this rifle has defied common recommendations and has shot unusually well considering it's design. And the use of VVN133 was a recommendation I received from an experienced Benchrest competitive shooter as one powder to try along with Varget and a few others which was done. In short, I done alot of testing early on to determine "the character" of the barrel that came on this rifle. Next comes the new barrel consideration. I bought the Kreiger 1:13.5 months ago in anticipation that one day it would time for the Savage barrel to be retired. I also contacted Dave Kiff at PTG and send him three samples of the Lapua Brass and Bart's 68's seated the my present settings to give him a measureable standard to send me a reamer to be used on the new Kreiger 1:13.5. I have that reamer in my safe as well. Lastly, Next week or so my Gunsmith will be scoping the Savage barrel to better determine the amount of erosion that may have already occurred and if the barrel is even worth saving. So that examination might tell us what decision I must make and the Kreiger may go on by pure default.

Lastly, I guess that Savage barrel has just performed well beyond anything I could have imagined and am unrealistically holding out for more in keep it on the rifle she came on. In many ways and as Patrick puts it, there are no guarantees, but the likelihood of even better accuracy is a good bet with the Kreiger. It's just that I have no experience with a 1:13.5 Kreiger even though it shoot lights out on a good friends Borden Actioned Match 6mmbr custom rig. He by the way uses Varget when competing and has a 22" barrel. My new Kreiger is 24" as she sit without ever having been mounted. Bottom line, just need to hear from other experienced folks like Patrick so I can "broaden my horizins" knowing I've done everything humanly possible while trying to get the most out of a fantastic "cross the counter" rifle that comes with inherent limitations of which I am aware. BTW, if I were competing, ain't no way in hell I'd be using this rifle to shoot against the those fine rigs that you see on a competition shooting line.

Keep the thoughts comin guys, pro or con. Thx!

Alex

 

[GSPV]

Also important is matching the freebore to the bullet.

In other words, regardless of the twist, a reamer for the long-heavies isn't going to be optimal for the short stubbies. Especially if you want to try Bart's boat tails.

Addendum: saw in the middle there where you have taken care of the reamer issue. Well played!

 

[Shynloco]

Now you know why I've learned over the years to call Dave Kiff and tell him what I'm after and what bullet/brass combo I'll be using so he can help me get the right reamer. Some guys are smart enough to figure all this out on their own. I'm not one of those fortunate few and hence one of my favorite saying, "I only shoot 'em, I don't fix or build them." My interests lie purely in precision reloading and accurate shooting. And there are plenty of smarter folks out here willing to lend a hand when I'm working on a project. Thx for the thoughts!

Alex

 

[MarkS]

Alex,

You have everything, do the new barrel. Keep the old one. The barrels are not hard to change on a Savage. I have found N135 works best in my BR's with 68 gr to 80gr bullets. I have had many Krieger barrel, no bad ones.

Good luck
Mark Schronce

 

[Shynloco]

Thx to all. And I've decided to go ahead and change out the barrel to the new 1:13.5 Kreiger. I'll keep the old one as Mark suggests and have my Gunsmith scope it for future use should I decide to start shooting long distance. I have a very experienced Gunsmith who does all the work on my rifles and is finishing up a custom 30br. So when he's done with that one, I'll have him change out the the Savage barrel as well. And Mark, I'll keep the VVN135 in mind as well. Now starts the hunt to find some.

Lastly, I appreciate everyone's thoughts and concerns as they helped me make up my mind on which way to go. Thx again.

Alex

 

[jonbearman]

Shynloco,keep checking powder valley as they seem to get some very few weeks or so.They just had n135 a few days ago.