Does anybody know of a gunsmith that specializes in accurizing Weatherby's? I have an Accumark in 7STW that won't get any tighter than about 1" or 1 1/4" @ 100 yards. This is acceptable factory accuracy for ranges out to about 400 yards or so, but I was hoping to stretch the envelope out to 600 or 700 yards and am looking for 1/2 to 3/4 moa. I'm capable of better accuracy (have a Sendero that shoots consistently under 1/2"). I think this is the gun.
Do you handload? This is a curious question. Weatherby uses quite a bit of "free-bore". This is very deterent to fine accuracy. But before any goes and starts beeting up on Weatherby, most other rifle manufactures use it. It allows for higher velocity, without the pressure signes. Some bullets don't like to "jump" into the lands, others are more forgiving in this matter. Sierra's are very forgiving, and thank goodness for that! Seating depth may be something that you should look at. Try checking how long the throat is in your paticular rifle. You may have 50 thou to jump.
Portate bien o te lleva el cucuy
Relatively new to handloading. Knew about the free bore and I've played with the over-all length. Have tried 140gr. ballistic tips, 160gr sierra gamekings, and multiple factory loadings (you would be amazed at the size of the hole a 160 gr. fail-safe will put into a caribou). Haven't tried switching powders yet (just finished the cannister I started with). I did everything you are supposed to do; broke the barrel in properly, cool down between shots, fire a fouling shot after cleaning, etc. Love the gun (bought at RMEF banquet), scope (Leupold Vari-X III 3.5-10x by 40mm), and love the cartridge (2 whitetail, 2 mule deer, 2 caribou; and the longest shot has been 155 yards, go figure?). What do you think? Switch to a model 700 and start over?
I have the same Weatherby rifle and caliber, 7STW. I too am frustrated on finding the right load. I have tried several powders and bullets and determined this rife to be inconsistant. This rifle will print .5 groups with 70.5 grains of IMR4831 topped off with a 130 grain Barnes XBT. This is when the Moon is in perfect alignment with the Earth and Sun. The same load will print 1.5 groups the following day. I enjoy short range shooting, (200 yards) with my Sako 22PPC. This website has given me the bug to try longer ranges...I hope the RIFLE GOD (AKA FIFTYDRIVER) can respond to my question. Can my Weatherby action be truely blue printed? I realize I will need to screw on a new quality tube to reach my goals, MOA 400-500 yards. I looked at picking up a Bat action and starting from scratch, but that project would take up to two years to avoid the wifes firearm radar...any response would be appreciated
I too had problems with my Accumark. The bullet my gun likes the best is Matchking.
I called weatherby, because some of the factory rounds were not achieving thier 1.5" guarantee.
They said to torque the action screws to 65in pounds. They also said to snug them up and then make sure the the action is centered in the stock. Then tighten the rear screw to 65 in-pounds then follow with the front screw.
I did not have a torque wrench, but I removed and resecured the action and my accuracy improved to sub-moa with some much better than that. I am new at this long range shooting and high performance rifles, but I think that the tightening that is required is to make up for poor bedding tolerances.
I too would like to hear from someone who has more experience. I does not give me a good confident feeling that this torque method is all that is wrong. I still seem to get bad first round fliers even from a dirty barrel.
I too set my action screws as specified by Weatherby using a torque wrench. I agree it shrunk my groups, but my rifle is still inconsistant.I believe my barrel is close to being shot out just by searching for the magic powder/load recipe. I think its time to screw a Krieger on, maybe turn it into a 6.5 STW if the "experts" believe my weatherby action is capable of MOA 4-500yds.Those Bats are expensive..Wade
To answer the question of if they can be accurized, certainly and to good effect. Only problem are those 54 bolt lugs they think they need [img]/ubbthreads/images/graemlins/tongue.gif[/img]!!!
Still, inconsistancy is generally caused by three main factors.
First is consistant pressure holding the receiver into the stock. This is where torquing the receiver screws comes into play.
Second is bedding. If the bedding is unstable you will get fliers weither its when the rifle hits up or right off the start. In this same area, the receiver screws need to be floated for consistant results. That means they should not touch the stock anywhere on teh body of the screw, only the threads should engage the receiver and the bolt head on the bottom metal.
If they do touch this can result in fliers as well. Generally they have to be touching pretty solid to really see a problem but it is a problem. It can also lead to a cracked stock in heavy kickers, float them screws.
The biggest problem with Wby rifles and any factory rifle really is that the chamber dimensions are generally quite loose. The area of critical concern is the throat and neck area but mostly the throat.
Freebore is really not a huge problem with accuracy as long as the diameter of the freebore is tight enough to support the bullet under pressure. I like a diameter of +0.0005" over bullet diameter for my big game rifles and +0.0002" to +0.0003" for my Bench type rifles. Match bullets used in bench guns are held to tighter tolernaces and this is why you can tighten up the throat a bit more without problems.
Generally factory throats are significantly larger in diameter then these numbers and as such there is room for that bullet to woller around in the throat after leaving the case mouth.
Hard bullets will not tolerate loose throats at all. The Barnes X and Fail safe bullets simply will not produce fine accuracy in a loose throated chamber. The reason is that they are so hard that they will not bump up under pressure to fill the larger diameter of the throat and then be swaged down into the bore consistantly.
A soft bullet such as the conventional cup jacketed bullets will bump upto make a better fit. This is why the Sierra Mk will generally shoot well out of most rifles that are set up true.
In the middle ground you have the Ballistic Tips with the solid copper bases that perform much better in tighter throats then loose but not as dramatically as hard bullets.
Another area that results in fliers is poor machining. IF a barrel is not threaded with a quality fit to the receiver it will vibrate more when fired then a quality fitted barrel would. This results in inconsistancy on target. Also, receiver faces can be out of square as can bolt faces, all resulting in variation from shot to shot. If the receiver face is un true, the barrel is stressed when it is torqued to teh receiver. This stress can result in fliers from the start or as the barrel heats up.
Machining and fit is critical to tight groups, I think that is obvious.
So yes, a Wby can certainly be accurized to get great results. Especially is a match grade barrel is fitted and a quality reamer is used to chamber the barrel.
They are like every other modern rifle, get everything true around one axis and give it a stable bedding and it will perform great.
Kirby Allen (50)
Allen Precision Shooting
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