Barrel Life .264WM

[DealHunter]

Picked up a very gently used Model 70 in .264 Win Mag (looks like a 1975 model) with a bore/throat that suggest it was barely if ever used.

I was wondering if there was anything specific I should do to keep the barrel in good shape when shooting since .264 WM has a reputation as a barrel burner.

Any recomendations?

[RC20]

I am shooting old military rifles. My approach is to shoot at as slow a speed as I can and get accuracy. I have found with the right bullet and power combo you can do that in 30-06 at 2200-2400 fps.

Not sure if that meets the desire for the use a magnum is put to but.....

[GeauxTide]

Not any harder on barrels than a 7mmRM. You'd have to shoot in the thousands to wear out a barrel. Just let your barrel cool down between shots when you're sighting in. John Barnsness wrote a recent article in Handloader on the 264.

[AllenJ]

Not allowing the barrel to overheat while shooting is very important, you could also stick with slow burning powders if you reload. In any event the barrel is going to eventually burn out, all barrels do when shot enough, the .264 just does it quicker. If this is going to be a hunting rifle and you only shoot a box of 20 cartridges a year, the barrel is going to last a long, long time. My uncle has been shooting his .264 for 20 plus years and it still shoots sub MOA.

[Bart B.]

It's been my observations that a .264 Win Mag's got about:

80% of the life of a 7mm Rem Mag.

50% of a .300 Win. Mag.

25% of a .30-06.

And about 20% of a .308 Win barrel's life.

My .264 Win Mag went from sub MOA groups at 600 yards to 3 MOA that far away in five shots starting with number 635. The throat had eroded almost 1/4 inch by then and the bullets were seated about 1/16th inch in the case mouth to just touch the rifling.

[4runnerman]

I have to go with Bart on this one. My friend had one ( best shooting rifle I think I have ever shot ) barrel burner #1. I don't think there is a rifle out there that will go through a barrel as fast as one of them,BUT--To this day,I can say It was the funnest and best rifle I have ever shot. I believe it was a 264 Winchester Magnum.

[publius]

Let the barrel cool between EVERY shot. This will help a lot but it still won't last as long as most chamberings.

[old roper]

I had one 264 build and 6.5x284 Norma both known barrel burners and their not for volume shooting. In a normal hunting rifle your not going to burn one out before 300mag least I didn't.

Today you have better bullets/powder.

[reynolds357]

I have several .264 Win mags. Keep the barrels cool and clean; you can get close to 1000 on a chrome moly barrel. Heat them up and you wont reach 500.
All but one of mine have been re-barreled. It is within 50 or so shots of getting a new Shilen.

[Bart B.]

Barrel life's something that's measured with a rubber ruler. By that, I mean that we all have a limit that our barrel's accuracy is considered not good enough. A benchrester will rebarrel when his 100-yard groups start averaging in the 2's instead of the 1's (2/10ths inch instead of 1/10th). A hunter wants a new barrel when his .30-06 no longer averages under 1 inch at 100 yards. A soldier gets a new barrel (or rifle) when it no longer shoots 2 inches or better at 100 yards. The benchrester gets 3000 rounds with his 22 and 24 caliber PPC ammo. Hunters using a .30-06 get 6000 rounds. Service rifle shooters with M1's and M14's as well as M16's get 9000 to 10000 rounds of barrel life.

Regarding rapid fire barrel life compared to slow fire, consider the following, which I think is a fair comparison.

Sierra Bullets shoots 30 caliber bullets 180-grains and less from .308 Win. cases testing them for accuracy. They shoot 10 shot groups from their rail gun in a minute or two; one shot every 10 to 15 seconds or so. This is repeated about every 20 minutes during a production run of bullets that are made at a rate of 90 per minute. That test barrel shoots match bullets into 1/2 inch average groups in their 200 yard indoor range. It's tested every several hundred rounds with "standard" bullets from a control lot. When those standards start shooting upwards of 3/4 inch average, the barrel's considered worn out. That happens at about 3000 rounds.

Palma rifles chambered for the .308 Win are fired once a minute for 17 to 20 shot strings. The good ones shoot under 3/4 MOA at long range starting out with a good barrel. When they begin shooting over 1 MOA, they're considered to be worn out. That happens at about 3000 rounds.

NRA match rifles in .308 Win have 1/3 of their barrel life shooting rapid fire matches, two 10-shot strings in 60 or 70 seconds each 10 minutes apart. 2/3rds of their life is slow fire shooting 1 shot per minute (or a bit less) in 10 or 20 shot strings. The good ones shoot under 1/2 MOA through 600 yards but get rebarreled when accuracy drops off by 50%. That happens at the same number as the others, about 3000 rounds of barrel life.

Barrel maker Boots Obermeyer has often stated that rapid fire does not wear out barrels any faster than slow fire when normal max pressure loads are used. It's those hot, over maximum, loads that cause the shorter barrel life. And some powders are more erosive than others, too.

Here's a link to a barrel life calculator:

http://www.accurateshooter.com/techn...l-barrel-life/

[old roper]

Bart B, I have a question and this is something you posted on 30cal could you expand and give life of a 264mag


I finally completed my research on a way to calculate how many rounds
a rifle barrel can be expected to deliver its accuracy level. By that,
I mean the barrel can be expected to have an average group size for
so many rounds before that average group size starts to get larger.

First, the rule-of-thumb formula I derived will produce a barrel accuracy
life of about 3000 rounds.

Second, if a lot of rapid fire (one shot every 5 to 10 seconds) is done,
the accuracy life will be less.

Third, if full-auto or very fast fire (a few shots per second, or one shot
every second) is done, accuracy life will be much less.

Fourth, the accuracy levels are for ranges through 600 yards. Once the
barrel life calculated limit is reached, groups will probably start to
get bigger at the longer ranges before they are noticeably bigger at the
shorter ranges.



If the powder charge is larger for this same bore size, the
barrel life will be shorter; for example a .300 Win. Mag. will last about
1100 rounds of original accuracy when shot no faster than once per minute.
But rapid fire will wear one out in only a few hundred shots.

My formula, or rule-of-thumb process, is:

1. Calculate the bore area in square millimeters.

2. Use one grain of powder for each square millimeter. This is what
I call the reference, or base powder charge.

Example: .30 caliber bore = 45.6 square millimeters.
Base powder charge for .30 caliber is 45.6 grains.

A .30 cal. cartridge that burns 45.6 grains of powder should give a
barrel life of about 3000 rounds of good accuracy.

3. If a larger cartridge is used and it burns more powder, the
accuracy life in rounds for that bore size is reduced. The amount
of reduction is determined by

a. Divide the increased charge by the base charge, then square
the answer.

b. Divide that answer into 3000.

[Bart B.]

Old Roper, that info was put in print by me in 1994 long before I got smarter learning more about barrel life talking with folks who make barrels and test bullets for accuracy.

I used to think Rem 700 receivers were stiffer than Win 70 ones. But it was easy to see by dynamic actual measurements and static rigidity calculations I was wrong. The 70's are near three times stiffer than the 700's.

[old roper]

Bart B. So nothing in this article is correct?

http://yarchive.net/gun/barrel/barrel_life.html

[Bart B.]

Old Roper, you're a tiny bit correct. The part:

Second, if a lot of rapid fire (one shot every 5 to 10 seconds) is done, the accuracy life will be less.

doesn't hold much water any more. At least in my opinion and that of some others. But the 3000 rounds for 1 grain of powder for each square millimeter of the bore's area is still good for rifles starting out at 1/4 MOA at 100 yards. Less accurate rifles will have a longer barrel life. 22 and 30 caliber service rifles have about 9,000 to 10,000 round barrel lives.

Mike Crawford used my basic formula for the one he put in accurateshooter.com (in my earlier post) for download. He added an entry for powder burn data; a good idea because different powders for a given bullet will end up with different barrel life. Some powders are more erosive than others. His barrel life numbers are typically more than mine. Depending on who's barrel life criteria data one uses as a "standard," any emperical formula will end up with different numbers.

[SansSouci]

DealHunter,

Very few hunters actually shoot enough to shoot-out a barrel. I'd bet that at most I've fired 20 hunting rounds a year. Just over a year ago I fired 4: 3 to assure my rifle was sighted and one to kill a buck.

I have a 40 year-old Model 700 that probably has been fired less than 200 times.

A .264 Win Mag is a hunting cartridge, and a damned good one at that. I'm sure that you could put a box of rounds through it every year off a bench and take it afield and never have to worry about its barrel.

I wish you success with your new rifle.

[RC20]

Does anyone have a list of the powders that cause higher erosion?

Rather than run a lot of calcs to find out it would be nice to know which ones to stay away from (hand loads of course) to extend barrel life.

No one has mentioned velocity either.

Slow it down would seem to extend barrel life.

[WIL TERRY]

AFTER SHOOTING 'EM FOR 50 YEARS NOW, I am so happy to be seeing guys talking about the 264WinMag again I can hardly contain myself !!!
The only one I never owned was a REM 700 and I am not sure why that state of affairs exists.
MY current 264 is a 26" Douglass XX MH tube on a commercial FN Magnum action, SAKO trigger, HTR French walnut stock, and an old 3x-9x Weaver scope. It will take 120gr bullets right up to 3400fps slick as you please.
I have shot groundhogs so far away with this rig you better make a second sandwich and pack extra water when you trek to get his earthly remains. ANd what it does to a 'yote...I yi yi yi yi.

[Bart B.]

RC20, in the link shown in post 20 in this thread, download the Excel file that calculates barrel life. In it's "Powder Heat Potential" box, when the cursor's put in it, a pop up window appears with a lot of powders shown with their number for it. Save that screen image to a file then you'll have a permanent record.

Compare those powder heat potential numbers with the powder's burning rate as shown in several sites by searching for "Powder Burn Rate."

[SansSouci]

WIL TERRY.

I've read more than one article the theses of which were had Remington not introduced its 7MM Rem Mag, the .264 Win Mag would have fared much better.

The .264 Win Mag is an excellent long range round with more than enough authority for all North American big game.

[reynolds357]

The biggest thing that hurt the .264 Win mag's popularity is the fact that it arrived at a time bullet technology was too poor for it to be fully useful for a big game rifle. Had the Barnes X been around when it was released, it would have sold like gang bangers.

[Bart B.]

Reynolds, I somewhat agree with your comments on bullet technology, but note that the 6.5x55 Swede was a popular big game cartridge in Europe and Africa as well as in the USA for decades. Several good hunting bullets were available at the time. Karamojo Bell used a Mannlicher-Schoenauer 6.5x54mm carbine dispatching many elephants in the early part of the last century.

The reverse is the issue for match bullets. Norma's 6.5mm 139-gr. FMJBT match bullet was popular in Europe for biathlon as well as free rifles in international competition at 300 metres. I used that bullet in my .264 Win. Mag. 1000-yard match rifle for a few years in the late 60's; they shot 1 MOA at 1000 yards. No accurate 26 caliber match bullet was made in the USA at the time. In 1969, Sierra Bullets gave me 200 of their .264" 140-gr. HPMK match bullets' first production run to test; best 20-shot groups at 1000 yards were almost 2 MOA; at 600 yards over 1 MOA. Sierra's ballistic tech told me he couldn't get consistant groups under 4/10ths MOA in their 100-yard test range with them. It wasn't until the middle 1990's that 26 caliber, long heavy match bullets could be made that shot 1/4 MOA in Sierra's test range. Jacket material wasn't good enough to make consistant dimensions for them. They had the same problems with their 28 caliber (7MM) 168-gr. HPMK bullets in the early 1970's when it came out and they didn't get better until the late 1980's.

[Sure Shot Mc Gee]

Any recomendations?

If your not a gunsmith but a reloader. I would shoot the slowest powder available for that 264 and somewhat lighter loadings not near its cartridge Max. History on 264 ownership has certainly not complemented the caliber in prior times. Every gun writers article I ever read concerning this caliber warned of its short coming. {Throat erosion} as we all know is greater in higher chamber pressure overbore cartridges. This was particularly true in the 1950s to early 1960s, with the chrome moly steels. But barrel advances with stainless steel, especially when cryogenically treated, have extended barrel life considerably concerning the venerable .264 Win. Mag. Being a 70ish model. You would have to judge what is appropriate and what isn't (ammo) for your barrels longevity.

[DealHunter]

A .264 Win Mag is a hunting cartridge, and a damned good one at that. I'm sure that you could put a box of rounds through it every year off a bench and take it afield and never have to worry about its barrel

And that's probably more what I'm looking at, I didn't get it as a bench/target rifle (besides the cost of factory stuff is pretty high).

[reynolds357]

Bart, when I first started deer hunting with the .264 Win. mag, I discovered very quickly that conventional bullet technology did not stand up to its velocity. At that time, there were only two bullets I could find for the rifle that could stand the velocity. This was before I ever heard of Midway etc. etc. If I wanted bullets, I went the sporting goods store and bought them. The two that would actually stand up to the velocity were the Speer Grand Slam and the Nosler Partition. If I am not mistaken, (venturing back before my time here) I do not think either was available when the .264 Win mag went into production. I do not know if Swift or Norma had bullets for it or not. In those days, no one around here had heard of either company.

[Bart B.]

Reynolds, I've shot 26 caliber bullets made in the '50's by Sierra, Hornady and others in my 1:9 twist .264 Win Mag in the late '60's and early '70's, Several 100-grain HP's were used on pasture poodles up to near 400 yards leaving at close to 3500 fps from the 28" barrel. None of them ever flew apart before impact. Only bullet I shot that came apart was a Norma 139-gr. nickel plated FMJBT match bullet; it did so about 200 yards from the muzzle.