Tuesday, October 12, 2010

Is the .257 Weatherby a Heavy Hitter?

Launching heavy for caliber 120 grain bullets in excess of 3200 feet per second, the .257 Weatherby offers ample power to flatten most game.

There seem to be two main camps that hunters tend to fall into when choosing cartridges.  There is the big bullet at moderate velocity camp, which is where I usually find myself since I struggle to find adequate arguments against big heavy bullets on game.   Then there is the small bullet at high velocity camp where so many modern hunters find themselves.  It is hard to find fault with this school of thought too, especially since the most widely hunted animal in North America is the whitetail deer , which, as a species,  just does not require the bone crushing power of 500 grain, 475 caliber bullets that I so enjoy.  In fact, it could be argued that only a handful of the animals on Earth require that level of power to bring to bag. 
To me the prime example of the small bullet at high velocity theory is the .257 Weatherby.  This cartridge is one of the flattest shooting, speediest hunting cartridges available.   Launching heavy for caliber 120 grain bullets in excess of 3200 feet per second, the .257 Weatherby offers ample power to flatten most game on this continent at considerable range.  Also of note is the entirely acceptable level of recoil.  Generally in my experience high performance is achieved at the expense of high recoil.  Such is just not the case with the .257 Weatherby.
Of course, the .257 Weatherby is not as widely available to hunters due to a very narrow selection of sporting arms made in this caliber.  That being said, the affordable Weatherby Vanguard is chambered in the Weatherby round.  The Vanguard is made in Japan by Howa and is identical to the Howa Model 1500 in many respects.  One of the nicest features in my mind is the price point.  I bought my rifle at a local chain sporting goods store for just under a third of the cost of a Mark V Weatherby
The action on the Vanguard is loosely based on the brilliant 98 Mauser pattern in that it incorporates two big lugs on the front of the bolt that lock solidly into the lug recesses in the front receiver ring, but there is no claw extractor on the Vanguard since it is a push feed action.  Extraction is accomplished by an M-16 style spring loaded extractor, and a plunger ejector is set in the bolt face to eject the cases.  The bolt features seven flutes along its length, which are finished in black and makes for a slick look against the polished bolt body.  There are also three vent holes in the bolt that will help channel gas out the ejection port of the rifle in the case of a blown primer or ruptured case.  In my mind, one of the nicer features of the Vanguard is the hinged, alloy floor plate, the release for which is nestled in the front of the trigger guard bow.  Many competing guns in this price point do not feature bottom metal at all so I see this as a nice touch.  The blued finish on the barreled action is even and looks good.  While it does not possess the deep blue, polished look of high end rifles, it is well done and at least as nice as other rifles on the market costing considerably more.

One thing I want to note about the scope is that it features rather thick crosshairs.  For really precise aiming, thinner crosshairs are preferred, but this is a hunting scope.  The thicker crosshairs are much easier to see as darkness approaches.   I could have used a target type scope for this project to really wring the accuracy out of the rifle, but I wanted to keep it simple.  The gun is a hunting gun so I put a hunting scope on it.   
To get ready for shooting, I free floated the barrel on this rifle.  I understand that many gun makers don’t want their loaner rifles tinkered with, but this is my rifle so I figured I could do whatever I wanted to it.  As received there was a “speed bump” under the barrel at the tip of the stock, and there was complete contact between the barrel and the stock along both sides of the barrel channel.  This is nothing a motivated guy and a Dremmel tool can’t remedy.  While I suppose there is some danger that free floating the barrel could make the gun shoot worse, I have never actually seen that.  In every case I have ever seen, accuracy is improved by floating the barrel.  I cannot say that accuracy was improved in this case because I did not shoot the rifle before I floated the barrel, but I can say that even when the barrel was too hot to touch during shooting, there was never any vertical stringing or any other anomalies.  The gun shot to the same point of aim on a cold bore shot as it did after shooting a five round string.  I am a believer in free floating, and this rifle only reinforced my beliefs.
As for the cartridge itself, I am in love.  It has proven to be an excellent cartridge to work with. I decided to shoot some Weatherby factory ammo in order to get a baseline on the performance I could expect with this gun as well as fire form some brass.  The only loads available nearby were loaded with 100 grain Hornady soft point bullets.  As a rule I am fond of Hornady bullets, but I am not fond of light for caliber bullets in magnum cartridges.  In my mind the point of magnums is to put more energy on target.   That can be done by adding velocity, by adding bullet mass, or by adding both velocity and mass.  This is where magnums shine. 
The Weatherby factory load averaged a bit over 3500 feet per second from my rifle.  This is blazing fast.  Again the bullets are light weight hunting bullets, not varmint bullets.  Cases showed flattened primers and shiny spots on the case head where the brass flowed into the ejector hole on the bolt face.  These are signs of a hot load that I as a handloader watch for when I make my ammo.  Bolt lift was normal however.  Still, I find it impressive that Weatherby factory ammo is loaded to top velocity and still shoots as accurately as it did.  Sub MOA groups were normal even though these were the first rounds fired through the rifle. 
My focus for handloading for the .257 Weatherby was the heavy hunting bullets in the 115-120 grain range.  I had a fantastic time loading different combinations of bullets and powders, and there are many combinations listed in the different load manuals to try.  When I began this project I wondered if I would have any barrel left for my own shooting and hunting after shooting all the combinations in the books.  Rest assured, the rifle is shooting more consistently and accurately now than it did at the very beginning.

All loads tested were taken directly from the load manuals.  If the overall length with a certain bullet was 3.225", then I loaded my ammo to that length.  I used the powder charge listed to the 1/10th grain, and I weighed each and every charge used in testing, trickling powder into the pan when needed to exactly as possible duplicate the published data.  I took great care to follow the load recipes exactly because I have no accurate way to measure pressure, and I wanted to make sure anyone reading this article would enjoy the safety of published, tested data.  The published data will allow loading the .257 Weatherby to levels that will do anything this cartridge would be asked to do. 
Of course there is one major exception to the statements above, and that has to do with primers.  The primer drought has mostly passed, and primers are to be found at reasonable prices again, but when I started this project, primers were scarce! I was first able to buy only Wolf brand magnum primers.  Eventually I was able to buy Winchester brand magnum primers, which I used throughout the remainder of the test with excellent results.  Thus I stuck to the published data as exactly as I could in every respect except for the primers, and in that case I used what I could get. 
The excellent Norma-made Weatherby brass was used exclusively for this project.  It is very consistent and is long lasting.  I obtained 100 pieces of Weatherby brass in addition to the  twenty pieces from shooting the box of factory ammo.  After I saw how the case head of the factory ammo looked after firing I was initially concerned that the brass would be a bit soft and after a few firings the primer pocket would get loose as the brass flowed under pressure.  Such was not the case.  The brass has been fired four or five times, depending on which loads were tested with that brass, and primer pockets are fine.  The brass is still shootable, and I have not lost a case to neck splitting or anything else.  This is very good brass considering I concentrated on the maximum loads listed in the manuals.

All shooting was conducted at my 100 yard range, and velocities were recorded twelve feet in front of the muzzle of the rifle.  I decided to measure three shot groups instead of 5 shot groups.  I am aware of the increased statistical accuracy of five shot groups over three shot groups, but after 3 shots in a row the barrel is wicked hot.  Any more shooting makes the barrel hotter still, and since I hoped to have a barrel with rifling left to shoot after all this testing, I decided three shot groups were plenty.  
Because my range is about an hour’s drive from my home I load batches of ammo, which I transport to the range for shooting.  This is where I hit the first snag in this project.  I had taken several loads featuring different bullets and powder combinations to the range for testing, but accurate data was impossible to obtain due to numerous hangfires and even a dud while using the Wolf magnum primers.  I had only experienced hangfires once before, and that was with some very dense ball powders and standard primers.  I sure did not expect magnum primers to be unable to consistently ignite extruded powders, and especially not while shooting in spring time in East Texas temperatures in the low 90s.  Most hangfires were delayed only enough to be barely perceptible, but others exhibited significant delays, and when the dud was encountered I ended the shooting session, brought all my gear back home and using my Forster press mounted collet bullet puller, I pulled the bullets from all the unfired cases to salvage the powder and bullets.

I even pulled the bullet from the dud cartridge.  Curiously, the powder was tightly compacted into a solid clump in the case under the bullet leaving an air gap at the bottom of the case.  This was discovered when I pushed a small diameter rod into the case to break up the clump of powder.  About ¾ of the way into the case, the rod broke through to the hollow part.  The powder came out of the case discolored, but unburned.  The primer had popped with enough force to compress the powder into the front of the case, but failed to ignite the powder.  The further use of the Wolf primers was discontinued.

The cases were reloaded using the same combinations of powders and bullets but this time with Winchester primers.  Not only were there no further issues with hangfires, the velocities I had measured with the Wolf primers were substantially lower than with the Winchester primers.   This is a no brainer really since Winchester primers are used in Winchester ammo, which is loaded with ball powders.  If the Winchester primers will ignite magnum quantities of ball powder, they should fire up extruded powders just fine, which they did.

There is an often repeated theory that the .257 Weatherby needs a 26 inch barrel to really do its thing.  I am not sure where that idea came from.  Of course the .257 Weatherby could do more with a longer barrel, but so can most centerfire cartridges.   Most load data in the various books lists maximum velocities in the 3200 foot second range for 120 grain bullets.  This was easily obtained with several bullet combinations using the 24 inch barrel on my Vanguard so I do not think a 26 inch tube is really necessary.
I tested powders on the slow to very slow end of the burn rate charts, but I found that the slowest powders out there are not needed in the 257 Wby.  In fact some are just plain too slow for it.  For example, IMR 7828 yielded velocities up to 155 fps slower than the book had projected with maximum loads.  While it is possible that powder would have benefitted from a longer barrel, there was a fair amount of powder residue almost half-way down the case body after firing indicating low pressure.    This phenomenon also occurred when using H-1000 and VihtaVouri N-165, which I had very high hopes for. 
H-1000 did perform very well with the 120 grain Swift A-Frame.  If there were any real surprises for me during all this testing, the 120 grain A-Frame was it.  This is a pure hunting bullet designed with toughness as the key element.  I found MOA accuracy with this bullet using H-1000, and at about 3100 fps, I am not sure which game animal on this continent it would not completely shoot through.  Sadly, the Swift reloading manual only lists this bullet with four different powders, two of which I was unable to obtain for this project.  I suspect I have not yet found the best load for this bullet.  Velocities may climb using different powders, but having shot a bunch of these bullets during testing, I doubt accuracy will deteriorate.  This bullet is my current do-all bullet for the .257 Weatherby. 
The excellent Nosler 115 grain Ballistic Tips proved to be super consistent in my rifle.  It shot at or below MOA accurately for me using several powders even though some of the highest velocity extreme spreads were recorded using this bullet.  For example, 66 grains of N-165 yielded an average velocity of 3141 with an extreme spread of 95.79 fps, but near MOA was obtained anyway.  That velocity is less than the Nosler manual suggests by 73 fps, but their data used a 26 inch barrel.   Fired cases featured powder residue all the way down the case to the extractor groove, which I have never seen before.  This implies to me that pressure does not build fast enough with this slow powder to effectively seal the chamber with the case until very late in the firing process. 
Excellent results were obtained with the Nosler Ballistic Tip using IMR 4831.  Sixty-four grains only averaged 3152 fps, but accuracy was great.  IMR 4350 turned in similar velocities and equal accuracy.  Several ½- ¾ MOA groups were shot with this bullet and these two powders.  Additionally shots from the two powders grouped very near the same place in relationship to the point of aim.  In theory, one could take rounds loaded with maximum charges listed for both powders and shoot them into the same group with similar velocity.   In all, I’d say IMR 4831 is the best powder for this bullet as extreme spreads were lower and velocity higher. 
Sierra bullets included in this project were the 117 grain Pro-Hunter spitzer, 117 grain Game King spitzer boat tail and the 120 grain hollow point boat tail.  Again, powders slower than the 4831s are not needed for these bullets.  In fact, Sierra’s Manual No. V does not list powders slower than the 4831s.  The 117 grain Game King BT averaged .953" accuracy and 3237 fps velocity using 63.7 grains of IMR 4831.  This velocity is slightly higher than the 3200 fps the book projected.  This same load pushed the flat based 117 grain Pro-Hunter to only 3173 fps, but turned in a group measuring .424".  The largest group I shot with this bullet and powder was 1.110".  Another load that impressed me was 66.7 grains of H 4831sc under the 117 Game King BT that averaged 3250 fps with a Standard deviation of only 19.05 fps and 1.127" accuracy, which is minute of whitetail anywhere, anytime.  Pairing the 120 grain HPBT with IMR 4350 averaged 3153 fps, but landed a group measuring only .367". It was difficult for me to find a load with the Sierra bullets that didn’t shoot great.  I have a bunch of the 120 grain HPBT bullets loaded up with IMR 4350 for the Fall, but I would not hesitate to hunt any deer in Texas with either of the three bullets by Sierra, nor would I hesitate to drop any of the plentiful wild hogs around here. 
I was unable to obtain any of the typically great Hornady bullets for these tests.  I would expect them to do well too.  I was really hoping to test their 117 grain Round Nose bullet, which is loaded in Weatherby factory ammo.  It is not a bullet that looks like it should excel in the .257 Weatherby, but I have had exceptional accuracy with it in three different .25-06 rifles, and I expect it would do equally great in the .257 Weatherby. 
All loads were assembled using Hornady dies.  These dies exhibit the typical high quality of Hornady products, but I would be remiss if I did not mention an issue I had with the dies.  The sizer works great, and produces very concentric cases; neck runout typically measures within .001"-.002". Sometimes when seating the bullets the alignment sleeve that slides up and down in the die binds and the case can only enter the die up to the shoulder.  Lowering the ram and jiggling the sleeve with a finger will fix this, but it is annoying.  To minimize this hassle, Hornady recommended adjusting the die body up in the press and adjusting the seating stem down for the same cartridge overall length.  This works 98% or so of the time, but I think if a longer die body were used the problem might be fixed permanently. Even with this issue, the dies create very concentric loaded ammo.  The seater die installs bullets into the case with minimal runout.  Normally the total runout measures in the .001"-.003", some of which, no doubt, is the bullet itself not being perfectly round.

In all I shot a bit over 550 rounds thru this rifle.  What did I find out?  I found that the 4831s, either H-4831 or IMR 4831 will do all that needs to be done in this cartridge.  This cartridge seems easy to please with a variety of bullets.  High end specialty bullets like the 120 grain Swift A-Frame shoot great while standard cup and core bullets like the 117 Sierra Pro-Hunter soft point also shoot great.  While I am sure I would have been able to find loads for lighter bullets, I don’t see why I would bother.  The 117-120 grain .257 caliber bullets boast a sectional density of around .260, which is higher than 140 grain 7mm bullets as well as 165 grain .308 caliber bullets.  The .257 Weatherby shoots the 120 grain bullet faster than the .300 Winchester magnum shoots 150 grain bullets.  It does this with less recoil to boot.  What is not to love?

.257 Weatherby Heavy Bullet Loads
Bullet Powder Charge Weight Average Velocity (fps) Notes
120gr Swift A-Frame H 1000 71.5 3075 Only 41 fps below book projections. S.D. 20.2 fps. ¾ MOA, My general purpose load
120gr Swift A-Frame IMR 7828 65.5 2959 Accurate, but 155 fps slower than book projection
120gr Sierra GameKing BTHP H 4831ssc 66.7 3181 19 ft below book. Sub MOA. Good Load with a pretty tough bullet
120gr Sierra GameKing BTHP IMR 4831 63.7 3161 Accurate, but slightly slower than with H- 4831ssc
117 Sierra GameKing BTSP IMR 4831 63.7 3237 Accurate. Well over book projection on velocity.
115gr Nosler BT IMR 4831 64.0 3152 Decent accuracy and velocity. Very consistent bullet/load combination. Different loads had the same point of impact. This suggests this bullet may be easy to work with in many rifles.
117 gr Sierra ProHunter SP IMR 4350 61.8 3132 Very accurate, velocity 80+/- fps below book
117 gr Sierra ProHunter SP IMR 4831 63.7 3173 Very accurate and consistent. My Texas whitetail load
117 Sierra GameKing BTSP H 4831ssc 66.7 3250 19.5 fps, faster than book projected. Sub MOA. Excellent load
WARNING The loads shown here are safe only in the guns for which they were developed. Neither the author nor InterMedia Outdoors Inc. assumes any liability for injury resulting from the use or misuse of this data.

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