30-06 Accuracy Improving

[Valornor]

Does anyone know why 30-06 isn't inherently less accurate than .308 Win?

I was looking at the SAAMI chamber drawings thinking perhaps the differences are there. The throats are clearly different, and my thought is if you cut a .308 Win throat in a .30-06 chamber would that improve the accuracy? Or is it more to have to with the shoulder angle and "Ackley Improving" the case would improve it.

The the only reason I'm screwing with it, is because I have a ton of 30-06 brass a a long action and would love to squeeze the extra velocity that I could get out of a 30-06 that I would normally lose in a .308.

[Blackwater]

If you want more velocity out of an '06, go to a longer barrel and the slowest powders that give top velocities, or maybe Superformance with some bullets in it. That would be my recommendation, anyway. I have one with a 26" barrel as a sporter (for "beanfield" shooting) and a HB match gun on an '03 Spfld. action that I set up like a 1920's or 30's target rifle, just because I love those old guns and have a lot of respect for those old shooters, and it's got a 26 5/8" barrel. The extra wt. makes it a real pussycat to shoot, despite the additional velocity. With careful and jucicious loading, you can get a fair amout over 3000 fps with 165/168's, and that ain't too shabby. Where you get your best accuracy at, velocity wise, though, can vary from gun to gun, and I'm not sure anyone has figured out exactly why. Too many variables, but some theories are pretty believable. And throats CAN, when tighter, increase pressures, thus limiting velocity a tad, but nothing of real importance. If you can make more out of what we currently know, or at least the part I've read, you're smarter than I am. I usually just let my 'smith worry about those things, and if he's got a good rep. for accuracy, that's what I tend to value much more than anything else. But that's me of course. Nothing wrong with wanting and diligently seeking more, or with experimenting. I've done some, and not all of them have been successful in reaching my goals. But that's how experimenting and testing goes sometimes. If you do this, let us know, will you? It's always interesting to get reports on this kind of thing.

[M-Tecs]

Both are capable of 1/4" MOA. The 308 uses less powder for the same velocity so the recoil is less. Pacific will grind you a reamer to your specs. I recommend following their recommendation. You just need to tell them what brass and bullets you are using.

[Valornor]

Not trying to get more velocity, just accuracy. I am building a target rifle on a Mauser action. The barrel will be 30" long velocity isn't the issue. It's also to make use of the brass I have.

I just didn't want to sink money into a .30-06 Sprg chamber and end up having regrets.

[Love Life]

I don't believe the 30-06 is inherently less accurate than the 308. I believe the 30-06 gets a bad rap due to the platforms used, shooter skill level, and loads used.

Using a custom built 30-06, quality components, painstaking hand loading, we achieved groups every bit as good as the 308's could produce from similar builds.

A quality barrel, quality action, and quality ammunition will give you the accuracy you want in spades.

[M-Tecs]

Not trying to get more velocity, just accuracy. I am building a target rifle on a Mauser action. The barrel will be 30" long velocity isn't the issue. It's also to make use of the brass I have.

I just didn't want to sink money into a .30-06 Sprg chamber and end up having regrets.

I would be more concerned about using a Mauser action as a base. Unless you are doing the work yourself you will have close to the same money into a Mauser as a state of the art target action. You will still have a marginally rigid action and a really slow lock time. That's why Mauser's fell out of favor in the mid 60's for the accuracy games If your 30" barrel has more mass than a light Palma I would look at barrel bedding blocks verse bedding the action.

I have only barreled 6 or 7 Mausers but I believe everyone of them grouped about 1/2 MOA larger than I expected.

What application or type of competition are you building the rifle for?

Before the Mauser fan boys get all up in arms I real like Mauser actions, but, as not a base for a target rifle. That ship last sailed in the mid 60's.

[MT Chambers]

I believe that the .308 is potentially more accurate then larger cases is the same reason the .30 br. is more accurate than the .308, shorter and more efficient. There is a reason the .308 and the 30 br. are winners in CBA benchrest comp.

[Valornor]

I'm on a budget, the Mauser action is what I have, with that said I'm ordering the barrel blank long in case I invest in a different action later on. It's a pet project and I'm doing a lot of the work myself. I really enjoy shooting iron sights, and I want to extend the range. It's hard to find a good bolt action with quality adjustable sights that I can reach out with. That's why I'm going with a long barrel, to increase the sight radius, and looking at a Phoenix Precision front and rear sight.

I shoot a lot of .308 Win. I also have a five gallon bucket full of 30-06 once fired brass that is all the same lot and fired in the same gun. I really hate to let that go, which is why I'm debating back and for what I want to do chambering wise on a rifle.

Likely I am splitting hairs when it comes to accuracy. I don't plan on competing with anyone besides myself. There's a few challenges done out here in Utah that deal with shooting a milk jug at distance. Of course most people have high end long range set ups with scopes. I have a rifle like that myself. I'm just looking to see if I can do it with irons.

I was looking at the chambers and was wondering if it had to more to do with the free bore cut into the .308 Win chamber. Yes the .308 Win is a more efficient design but it's also originally designed to work with modern spritzer type bullets. Where as the 30-06 was designed around a much heavier 220 grain bullet, and the chamber is similar to chamber designs of the era that worked best with long tangential ogive bullet.

SAAMI pressure for .308 Win is also higher than .30-06 so I dont buy that the "Push" is some how less violent, plus 30-06 uses slower powders and the rise time for pressures in a 30-06 are also slower. Again that's where I was curious if anyone had tried cutting the freebore/throat in a .30-06 to match that of a .308 Win and see if that made a difference.

It could also be the longer action required for a .30-06 is less rigid and that is the difference. I don't know. At this point I'm just curious to know if anyone had done anything differently and gotten better or worse results. That or if trying to get 1-3/4 MOA performance out of a .30-06 cartridge is just no feasible. (Realizing that the action and barrel play a lot into that as well.)

[M-Tecs]

None of the accuracy smiths are using SAAMI spec reamers. I own 8 different 308 reamers. Seven are carbide and all ground for a specific applications. None of them are SAAMI Spec. I highly recommend Dave Kiff owner of Pacific Tool and Gauge for advice as to what will perform best for your application. You can also send him loaded rounds to have the reamer custom ground for maximum accuracy. They rent reamers also.

Even with the Mauser action 5/8 to 3/4" MOA with jacketed match bullets should be very doable.

good read here http://bulletin.accurateshooter.com/2011/04/308-win-vs-30-06-match-results-may-surprise-you/

Here are a couple of good site to see what the current winning builders are using.

http://www.accurateshooter.com/

http://benchrest.com/forum.php

http://benchrest.com/forumdisplay.php?17-Gunsmiths-Corner

Dave would have very good insight as to the best cast bullet reamer design.

http://castbulletassoc.org/ and the Fouling Shot post what the match winners are using.

[Valornor]

Perfect that's exactly what I am looking for. Thank you for the links.

[Blackwater]

M-Tecs gives good advice. As to wanting to build a real tack driver, the Mauser can be very accurate, but its flaw is that most of the metal is cut away in the action area to make room for the magazine and loading port. This lets it flex more than a single shot action where the bottom of the action's metal is still there to support and "stiffen" the action. But unless you're measuring your groups with a micrometer or caliper, you ought to be able to make a very nice rifle. I've long loved old Mausers and '03 Springfields for sporters, and have that one "match" rifle with HB in '06. It still needs some work

One tip. Bedding is generally a huge part of what gives us accuracy. With a more flexible action, like a Mauser, you might want to try various bedding techniques on it, to see which works best for you. A full length (of the forend) bedding gives long, heavy barrels a lot more support, and sometimes helps a more flexible action like a Mauser, but it also tends to make long strings give POI's that rise as the barrel heats up. Not a lot, but when you're shooting at fly specks, enough to matter. And once you establish how much each shot raises the POI, you can compensate for it, because it should be pretty consistent. Real, hard core accuracy seeking makes a lot of little things we never noticed before matter more than it looks like they ought to. But that's one reason the same guys seem to win wherever they go, or at least place very high in competition. They watch those "little things" more closely and obsessively than others. Just a FWIW, in case you might find it useful, if you in fact didn't already know all this.

[Bigslug]

Half-minute with the .30-06 is not a particularly difficult thing to achieve in the standard chamber, and whatever it throws will be faster and more resistant to wind and drop than the same pill sent forth from a .308.

Yes there's the short, fat powder column and the short, stiff action that a lot of folks tout as .308 advantages, but bedding matters, action screw torque matters, and choosing powders with an eye to load density matters. The advantages that the .308 theoretically does have are all at traditional Benchrest distances of 200 yards and in. When you have to start fighting conditions, the ability to throw bigger and/or faster will tell.

I've done the .30-06 Ackley thing and liked it. In a 31" barrel I've had moly-coated 175 grain Matchkings exceed 3000 fps and settled on an accuracy load of the 190 grain version a bit over 2900. It's an extremely accurate gun, but I consider that more down to the build quality than the cartridge design. To do over again, I'd probably do it in the standard '06. My daily knock-around hunting rifle is a totally unmodified Remington 700 .30-06 with no free float and it has been boringly 1/2 MOA at every zero verification session since it came home new in 2012 - - - -I have no doubts about the cartridge.

On a barrel as long as you're planning, I would suggest you bed the barrel forward of the action as far as the chamber. This will take the weight of your heavy tube off the threads of the action.

[samari46]

Been shooting both 30-06 and 308 for some years now and found that it was easier for me to get better accuracy out of the '06 than 308. The '06's have been mostly Winchester target rifles both with factory and after market barrels. And of course my Sako 75 hunter. I basically use the same load in all the '06's and never had the cause to be disappointed. 308's were one Winchester M70 with factory barrel, one Savage 110FP, Remington 700 sendero and 40x single shot 7.62 nato. Bullets were mostly 168 SMK's and for the Sako 165 Nosler Ballistic tips and some old Lake City M72 match ammo. Still have a M70 factory stock match rifle in '06 that I haven't shot yet but barrel is pristine so don't doubt it will shoot. Frank

[Scharfschuetze]

I have three Winchester Model 70 match rifles, one in Ought Six (Pre 64 on its second barrel) and two in 308 Winchester (one Pre 64 with a second barrel and one a Post 63 with original barrel). To be honest, there isn't a bit of difference between them as far as accuracy goes. The Ought Six does handle anything over 800 yards better than the 308s as I can shoot 185 grain Berger VLDs or 190 grain Sierra Match Kings at usable velocities from it. All three rifles will shoot 3/4 MOA with SMKs or Berger VLDs all day every day.

I once built an Ought Six on a WW I Mauser action. I actually made the barrel from a barrel steel dowel while working part time for a gunsmith in Killeen, Texas. It was a sporter weight rifle for hunting, but it shot as well as any other quality rifle with proper loads.

As noted above, bedding is key as well as a good quality barrel. Were I building one today, I'd opt for a 1 in 12" twist rather than the usual 1 in 10" twist for the Ought Six.

[runfiverun]

spend the money on a good barrel.
the 30-06 can be very, very accurate.
my 30-06 Bergara will shoot groups smaller than I thought a hunting rifle should.
it will just squeak out my 25-06 on a mauser action, but is on Par with my 300XCB on another mauser action.
the two 30 cals have very, very good barrels on them, the 0-6 just has a better trigger on it [for now] once the XCB gets the Huber trigger like I put on the 25-06 it will shoot just as well as or better than the 0-6.
oh the XCB is basically the 8 mauser case with the 0-6 neck and shoulder and throat pressed into service on the front end.
both of them will shoot right there with my 30AR rifle in 308, only at a higher velocity.

the one thing all of those very accurate rifles have in common is high quality, straight Barrels, with the chamber cut square to the bore.

[Valornor]

Thank you for the insights and field reports. That makes me feel a little more confident that I won't regret choosing a 30-06. I was looking at maybe using the 190gr SMK or similar style bullets I swage my self since the long barrel would likely launch those pills at a very favorable velocity.

I didn't want to go to 300 Win mag, and my goal would never be trying to get magnum performance from a 30-06. No sense in beating up action or barrel. But the heavier bullet weight and extra velocity I could get out of the 30-06 in my mind seemed to point to that as been a better cartridge for 800+ yards. Especially with the modern powders.

[izzyjoe]

I truly think the 06 got a bad rap because of recoil, and that caused some folk to flinch. I remember my uncle always telling me a 30-06 just had to much recoil, but as I got older and shot few of them I found there not that bad. Now a light rifle will tend to get on you after a few rounds, but an 8# rifle is tolerable.

[Tom W.]

I rechambered my Ruger #1 b to a 30-06 A.I. Even the loads I made up for fireforming are remarkably accurate. The rifle likes IMR 4350 the best, although I don't. It loves the 180 gr. Sierra GameKings. I suppose it's how or what you feed it.

[samari46]

All I ever used in the '06 was IMR 4350. CCI 250 magnum primer. Why the magnum primer?. Because tests over a chronograph have shown me it gives consistency to the load. I normally use 54.5 to 55.5 grains as that was the sweet spot when using 168SMK's. I've used no other powder than IMR 4350 in at least a half dozen '06's Frank

[Tom W.]

It's just too sharp of a recoil for me. Some of the Alliant powders do my old bones better. But it's a very accurate powder, for sure.

[Blackwater]

The old '06 IS probably the finest "all around" caliber ever developed. It wasn't developed to be that. It's just how it all eventually worked out. I believe Elanor O'Connor shot her lion with the '06 and 220 gr. bullets way back when. It's also been used on buff and elephants and rhino when folks got caught in a bad situation unexpectedly, and it was all they HAD to "fight" with. However, it DOES also represent about the maximum limit many folks can tolerate on the recoil end of it. I don't know how many guys I've known who missed a deer, and said it wasn't enough, got a .300 mag., and were afraid to pull the trigger on it. Many of them never hit a deer with it because they jerked the trigger, and missed even WORSE than they had with an '06. We seem to be becoming progressively less tolerant of recoil, but in an 8 lb. sporter, with a pad, it ought to be tolerable by most shooters who are willing to learn the discipline necessary to overcome their fears of recoil. Muzzle blast is also a factor in perception of recoil, and many react more to that than the actual recoil. Most of those insist on shooting without muffs - a very foolish and far too "macho" situation!

But many have put forth the precept that accuracy is NOT a function of caliber, but of the rifle's fit and the precision with which it's built. Square and concentric chambers are always an asset. Throat dimensions can be a factor. But mostly, accuracy is just a function and result of all the care and precision built into the gun by the 'smith who does the work. It's that extra precision and detail work that makes "real" target rifles so much more expensive and accurate than off-the-shelf sporters made en masse for the average shooter. The loads you feed it, and their OAL and other specs, also play into the equation, and it takes some actual shooting to find out what your own, personal, individual rifle wants in order to shoot its best. There are some general guidelines, like neck sizing cases where possible, charge wt. and specific bullet and its jump to the rifling (if any), etc., etc., etc.

There's a reason the same shooters tend to always find their names at or near the top in matches, and mostly, it's really just a matter of how they manage the details - the "little things" that many are too impatient to attend to - that makes them so consistently at or near the top of the winners' lists. Accuracy is a goal, not a destination. Its pursuit will always be tenuous. I've seen many who just selected some arbitrary load, shot it, and if it didn't shoot, blamed the rifle. That's not how one finds accuracy, usually. It's found by first off, getting as well made a rifle as one can afford, and it's quite surprising how off-the-shelf guns perform with a little knowledgeable experimenting. I've seen them shoot 3/8" groups for FIVE shots, and do it consistently. 5/8" isn't uncommon IF the shooter works up his loads properly and tests various bullets. Sub-MOA is common. BUT .... you DO have to develop your loads to match what your rifle likes. It's all "hard work," at least in the mind of most today. I always looked at it as fun and interesting, and an excuse to shoot more, and learn something from it - at least for that particular rifle. I once found that Hornady Light Magnums in 150 gr. shot better than my traditional loads - a very embarassing situation! But its throat was pretty worn, and I rebarreled it. Now, it'll shoot like it's got eyes! Still an '06, but with a Shilen barrel now.

Accuracy is always going to be a goal, and one that can be elusive unless we learn a good bit about what causes it to be enhanced in most rifles. And even then, you'll encounter some that will defy the "rules," and want something you'd never have expected to shoot its best. If anyone has ever figured out why this is, let me know. I've heard theories, but no real "answers." Testing on target will always be the ONLY way to establish what a rifle will shoot, and what it doesn't particularly like. And that's just how it is, unless someone has found a better way.

[monge]

Well said Blackwater spot on!

[Regulator.]

Does anyone know why 30-06 isn't inherently less accurate than .308 Win?
.......

If I was building your 30-06 for accuracy.. Reamer would be the Serengeti match from PTG, barrel would be a Broughton, or Krieger. Twist would not be a 1-10, if your goal is to shoot heavier than 150/168grs to the 180grs I would recommend 1-12 to even as slow as 1-13" if you was staying with the 150ish I would go to 1-4 to maybe even 1-15 depending on your goals. On bore and groove while the .298x307 is definitely the palma boys choice and not a bad one. I would say the 300x308 would be the one to use.
The 1-10 twist is useful for the 200ish plus weight.

Every time I hear a 308 is inherently more accurate than the 30-06 I will 90 percent of the time tear that 308 shooters soul out of whack with a 30-06, the other 10 percent I'll tie him. Top performing loads in accuracy are not at the max speed usually top speed = more recoil= stress and fatigue on the shooter. So reduced, comfortable accurate loads for the shorter to midrange distances (100- 600 yards) are the order of the day. Only turn the beast loose for those long range shots 1000 plus yards.
More marksmanship trophies have fell to the 30-06 than any other cartridge.

[monge]

most may not believe this ,but I have a savage axis 30-06 that will shoot 3/4" five shot groups at 200yards Stock gun my trigger job ,Boyds stock and careful hand loads. 165gr spbt at 2850fps

[ole 5 hole group]

All I know is I enjoy both calibers. If the military still had the 30-06 as standard issue - most world records would be currently held with the 30-06, as the Service Team Members know how to shoot and their Armorers know how to put together a match rifle.

I've only used Remington 700 actions for builds - trued/blueprinted whatever, Match grade barrels from several different makers, several different stocks and what I found was some barrels shot better than others - even from the same barrel maker but the bedding blocks and bedding had to be perfect.

The longer the range, the better the rifleman had to be - I always knew my rifle could shoot better than I could hold but that's the way I wanted it, so I could get better - problem being, I never got good enough.;-)

[W.R.Buchanan]

I would think this "Target Rifle" would be at least 10 lbs and at that weight recoil shouldn't be a issue.

Also there are recoil pads which do a pretty good job of knocking it down.

just sayin'

Randy