6mmBR build advice needed

[SS427]

I’m looking to buy a 6mmBR for 100-200 yard benchrest shooting that will do double duty as a varmint rifle for sage rats in the Western United States. Because my local shooting range has a 200 yard limit, and sage rats are not exactly a long range challenge, I’m not concerned at this point about 400 plus yardage shooting. In the future I will be shooting longer distances, but at that point I would be swapping out barrels.

My goal is the best accuracy I can get with light target bullets. I also want to be able to shoot 70 grain Sierra Matchking and Blitzking bullets, as well as the same weight of Nosler Ballistic Tips. I don’t foresee a need to shoot anything heavier than that for now.

I plan to have a Krieger heavy varmint barrel installed, but I dislike the way really long versions of these barrels balance while being carried in the field. On the other hand I anticipate a slow twist barrel, so I don’t want to go too short and give up velocity. My understanding is you can get away shooting a heavier/longer bullet in a slow twist barrel provided you can get the velocity high enough.

My first question is what would be the ideal twist for the above requirements? Remember, ultimate accuracy out of the caliber is what I’m after.

My second question is what is the shortest length of barrel I could get away with that wouldn’t compromise velocity that much?

Some of you might suggest a 6mmPPC, but I’m not interested in that much brass prep effort, and eventually I will want to install an 8 twist barrel for longer range shooting.

 

[holstil]

Sounds like your talking yourself into a ppc and a 6br. You can have a switch barrel gun. Go ahead and get a 6ppc no turn, then when ready get the 6br throated for the heavies. The ppc should do fine out to 400yds or more anyway.
Good luck, Jim

 

[cmillard]

check out the savage line of target rifles--they might have what you are looking for.

 

[SS427]

I have a Savage LRPV .223, and have not been overly impressed. Fouls really bad, and accuracy is only so-so. The twist options are restricted for the Savage 6mmBR to 8 and 12. I have two other Savages, and for factory guns they are pretty nice, but I'm ready to step up to a custom action like a Panda or Bat, with a Krieger or Bartlein barrel.

I'm convinced 6mmPPC is not what I want. I don't want to fireform brass, and unless you turn the necks down, I don't think the accuracy would be much better than a 6mmBR.

I've read about every article on this website. I just want some of the forum members to confirm some of the stuff I've read regarding twist and barrel length, both on this webiste and many others. Most of what I read is probably trustworthy, but I like to get confirmation from people with experience.

 

[SS427]

Lynn - thanks for the reply. I understand the freebore statement. I figure I will be getting best accuracy either at the lands or jammed, so I'll want a short freebore. What is the 1.5 degree leade? I don't recall reading about this.

I was planning on a 26 inch barrel, but I don't like that extra weight on the end. Had talked myself into a 24 inch barrel, but now I'm wondering if even shorter might be a good idea. I'm under the impression a 21 to 22 inch barrel gives the best accuracy with the bullet weight I'm going to be using. I'm just concerned about the loss in velocity. I figure about a 30fps loss of velocity per inch of barrel reduction.

 

[Toby Bradshaw]

For target work at 100-200yd and sage rats out to 300-400yd you might consider a no-turn (0.253 neck) .220 Russian or .220 Beggs. Great brass, no fireforming, good velocity (~3500fps) with 52-55gr bullets from any 1:14tw barrel length >21".

There is a 6 Beggs, too, which is a pretty much a no-fireform PPC equivalent, but the .22s are more pleasant to shoot -- considerably less recoil.

If you get a Panda with a 0.473 bolt face it will pull the PPC head size without any issues (as long as you aren't using an ejector). Then, when you want to do some longer range work you get a 6BR 1:8 barrel.

I don't know if the BAT will work with both head sizes.

Toby Bradshaw
baywingdb@comcast.net

 

[SS427]

Toby - does anyone even chamber for the .220 Russian any more? I don't recall reading anything about this chamber other than the history of when the Russians started using it for benchrest shooting to spite the .222 Rem. Mostly what I know about the .220 Russian is the brass is used to form PPC brass. I don't see a lot of load data for the cartridge and I'm not sure the accuracy would be any better than a .222 Rem. You have sparked an interest though....probably not this gun, but maybe the next. I do like the .22 caliber centerfires.

 

[Toby Bradshaw]

Go over to benchrest.com and search for "220 Beggs." Gene's 220 and 6 are identical to the .220 Russian except for having a smaller radius at the neck/shoulder junction to prevent excessive case length growth. The .220 Russian (and Beggs) have the same case capacity as the 22PPC-100, without the case forming headaches. Dies are readily available for either the Russian or Beggs cases, with matching reamers available from PTG.

I love my .222 (especially now that Lapua makes brass for it), but the .220 Russian (or Beggs) has at least three advantages over the .222 Rem:

1) the .220s will give you about 300-400fps more velocity; 2) the PPC and BR cases can be used with the same action/bolt face (at least it works fine on my Panda and Stiller Predator); and, 3) the .222 Rem is a longer case with a larger flash hole. Reason #2 is especially important to me -- I like to be able to set up a small .22 centerfire (.220 Beggs) for short-range LV/HV, a 6PPC for Sporter (and LV/HV, if desired), a 30BR for short-range score shooting, and a fast-twist 6BR for longer-range work, all using the same Panda.

Toby Bradshaw
baywingdb@comcast.net

 

[fdshuster]

otter: So many choices, so many decisions to make. Depends on how far you want to go. Two of my 6BR's are 1-14 (Shilen & Hart), another is a re-chambered Savage factory 1-9.25, and the fourth is a Hart 1-8. Just verified the other day (again) that the 1-8 does a fine job with the "little" 68 gr. Berger Match HPFB, with mulitple 5 shot groups at 200 yd. It also is a performer at 500 yds. ( the longest distance I've been able to go, so far), with the 95 gr Berger VLD's. So, the 8 twist (.272" no-turn neck) will have the added benefit of a wider range of bullet weights. If you are sure to not go beyond about 300 yds., then a 1-14 is a good choice, but heaviest bullit weights will probably be in the 75 gr. area. A 24" light to medium varmint contour would be my consideration. The Remington factory varmint contour is a very popular barrel choice. I am leaning more and more to no-turn necks with the ever superior Lapua brass, of course. Unless you get radical on barrel length, I don't believe it's that important as it relates to velocity loss or gain, so I do prefer the 24", but do have some 26", mainly so they can be set-back and re-chambered when the serious fire-cracking develops in the throat. Have set-back several & they have all been "successful". The type of stock you choose is also important: with a poor one (like a lot of factory versions) the potential of the barrel and cartridge will always be in question, and probably never realized. A switch-barrel is another choice: I have several now, so even more possibilities are open to---- more decisions. We are blessed with so many options. I've been in contact with a very active shooter/reloader in France, and his options/choices are extremely limited. I don't want to keep rambling on: if any questions/comments, feel free to send a PM.

 

[North Fork]

If it was me i would order two barrels one for bench rest shooting and one varmint shooting.That way you are not burning up your bench rest barrel on sage rats.I have a 1x13 and two 1x8 twist all three are no turn necks the 1x13 likes 68gr Berger's and 70gr sierras the 1x8 likes 105 and 107 and 108gr bullets.my barrels are all 26inch

 

[SS427]

Frank - thanks for the reply. I've found your posts informative and accurate. Your response has help confirm what I've read up to this point. May take you up later on the PM offer as I get farther into this purchase.

North Fork - would like to buy two barrels, but the $$$ just for the gun is enough to finance a small family for a few months. Just can't afford it right now. I'm new to the caliber so I'm facing about $300 worth of other purchases like dies, brass, and all the other stuff that goes along with it. The 6mmBR won't see a lot of rat action. I have a number of other guns that will see the bulk of the action during a furious sage rat trip.

 

[MarkS]

Otter,

You did not say what type of gun you are building. Or if you were going to buy a used gun. I would look at a used benchrest gun you can pick then up cheap. Most would be PPC, you have the boltface opened to BR and the barrel punched to 6BR. The bench gunmake great switch barrel gun, I have 3 with 2 barrels each.

A weight system in the stock would be the way to go for muliti barrel gun, you could balance it out with different barrels length.

The short barrels will shoot great and the velocity want fall much. I did a used benchest gun and had it opened up the 6BR. The velocity ran 3500 f/s with 65 gr benchrest bullets.

Go with the 0.272 no turn neck for Lapua brass. I have 2 12 tw 6BR gun That I like very well. You can shoot 80 gr bullets very well , but will shoot the lighter bullets very well . I shoot the bullets, you have picked the 68 Berger and 70 Blitzking. I have kills out to 620 yds on VA groundhogs.

The set up you are looking at will shoot out to 600 yds with no problem.

Mark Schronce

 

[SS427]

Mark - I'm looking to have a new gun built by someone like Kelby or one of the guns offered by Bruno's. I'm not interested in a used gun as I don't want to run the risk of getting ripped off. I would want to inspect anything before I bought it and that is hard to do without a lot of hassle. I don't know a local gunsmith I would trust to build a rifle of this quality.

My plan is to get it with a .272 no turn barrel. I have already ordered Lapua brass. I'm not sure which bushing size to order with the dies though. From what I've read I should probably order a .267, a .268 and a .266. Never had to order bushings without having loaded ammo to measure from, since I've always had cheap non bushing dies that I loaded with before stepping up to higher quality dies.

 

[MarkS]

Otter,

Yes I know about getting a used gun, I would have to see it. I have got mine from people I know. Kelby and Bruno do good work.

I use a 0.267 for target loads and 0.266 for hunting loads. I don't think you would need a 0.268, most brass runs 0.2685" to 0.2690" loaded.

N135 has been the go to powder for all my Br's with lighter bullets up to 80gr , Varget and RL 15 with 87gr Vmax and up.

Mark Schronce

 

[Toby Bradshaw]

I don't know a local gunsmith I would trust to build a rifle of this quality.

Where do you live?

My plan is to get it with a .272 no turn barrel. I have already ordered Lapua brass. I'm not sure which bushing size to order with the dies though. From what I've read I should probably order a .267, a .268 and a .266. Never had to order bushings without having loaded ammo to measure from, since I've always had cheap non bushing dies that I loaded with before stepping up to higher quality dies.

My chamber has a 0.272 neck, my loaded rounds measure 0.2695-0.2700 depending on whether I'm shooting a BT or FB, and I use a 0.268 bushing most of the time. I can't imagine that you will need a 0.266 bushing.

Toby Bradshaw
baywingdb@comcast.net

 

[SS427]

Toby - I live in Oregon. I have a local gunsmith I trust for trigger work, and he could probably do a good job with a custom build. But I'm not willing to gamble the kind of money involved with a custom rifle to find out I was wrong.

Thanks for the bushing info. I'm thinking I will order a .268 and go from there. I've been shooting a .223 with only .001 tension with very good results. Does the weight of the bullet have anything to do with needing more or less neck tension? Or does it all depend on the individual chamber?

 

[Toby Bradshaw]

I figured that you lived somewhere in the PNW. I hunt jackrabbits with my hawks in the Ft. Rock valley for a few months each year -- lots of sage rats there.

I'd be surprised if there aren't some good BR gunsmiths in OR. If you don't mind driving to WA I can recommend Steve Kostanich and Rick Beginski. Serious shooters (world record BR shooters) and dedicated to making accurate rifles. Email me if you want their contact info.

Nothing wrong with having Kelbly's or Lester Bruno build you a rifle, but it's nice to have a local smith.

Toby Bradshaw
baywingdb@comcast.net

 

[SS427]

Toby - never have hunted the Ft. Rock/Christmas Valley area for rats. I've heard most the ranches now limit you to rimfires, and many of them limit you to .22lr. I have a ranch in Unity and one in Lakeview that I hunt and they allow centerfires and have lots of rats. Hunting rabbits with hawks sounds like a blast.

The prices being offered by Kelby and Bruno are so competitive right now, I'm not sure I could save much by going with a local gunsmith. I figure if anyone can build an accurate rifle, these guys would. My biggest worry is I will get a custom rifle and it will only be marginally more accurate than my Remington and Savage varmint rifles. Both these guns can shoot in the .3s and .4s, with a few groups in the .5s. I sure hope I end up with a rifle that can consistently shoot in the .2s and .3s.

 

[Toby Bradshaw]

My biggest worry is I will get a custom rifle and it will only be marginally more accurate than my Remington and Savage varmint rifles.

Fear not. Your new BR rifle will put any factory rifle in the very deep shade.

If you get your rifle from Lester be sure to ask him to send you some of his 68gr bullets, and to suggest a load. Very likely if you take his advice you can go straight to the range and shoot 1s and 2s in good conditions at 100yd. It won't take you more than a few groups to figure out what all the fuss over custom actions, barrels, triggers, and stocks is about.

Toby Bradshaw
baywingdb@comcast.net