WEATHERBY ACCUMARK V 338/378- WHAT ACCURACY TO EXPECT ?

[Coyboy]

DUH, had a custom 338 edge built, and is killing everything on Gods green earth with it. I am positive he was glad he did not purchase a Weatherby. I have seen frustrated customers in my shop with Weatherbys that refused to shoot, and a Manf. who was not willing to make them happy. Soon they will be the GM of rifle builders. If it wasn't for the Vangaurd/Howa rifle they would already be a Government subsidie.

Did you notice this topic is 2 years old.

 

[tlglvsguns]

The Accumark in 338-378 that I regularly work with likes 225TSX's with RL-25 at 3300 fps. This one doesn't even have the trigger adjusted. Shoots 1/2" 3 shot groups with no cooling between shots. My personal Accumarks are all bedded now and shoot better than that. My best 3 shot group 300Wby Accumark from a hot barrel is right at 3" at 885 yards. The load is 200AB at 3100 fps. The wind just died and I had to shoot with a hot barrel. Earlier that same day none of us could even hit that target.
After skim bedding my 3 Accumarks make a lot of these.

What's skim bedding? And is that all you did to make it shoot that tight?

 

[canadianshooter]

I have a accumark in 338/378 and I average 3/4 inch to 1 inch groups with 225 grain Hornady SST with 101 to 102 grains reloader 25. I also get 5/8 to 1 inch groups with sierra 250 match kings with Retumbo, good rifle for right out of the box. I broke in the barrel and this rifle rocks!! I have the Bushnell elite 6500 in 4.5 by 30 with DOA reticle for now. The rifle has milder recoil with or without the brake than my vanguard back country in .300 win mag. Then again that was after shooting a box with my .416 Rigby with 400 grains!!

 

[Long Time Long Ranger]

The 338-378 accumark is as good a long range hunting rifle as you can get. All I have ever seen come through the shop would have no problem taking game at a half mile with minor work you would do with any new factory rifle. Velocity with a 26" barrel would average about 100 fps faster than a 30" 338-300 ultramag. You would also have the best platform available for a rebarrel job at some later date if you wanted. A $400 barrel from pac-nor would be awesome on the accumark.

If you have a magnum action or can get one fairly cheap then a 338-300 ultramag barrel from pac-nor and you will have a very good long range rifle. Back in the 90's I did around seventy five 338-300 ultramags with pac-nor barrels and they all shot extremely well. Pac-nor quality is among the best. You can get a headspace guage from midway and you are in business. Screw it in, headspace and bed it the way you like and it will be a very good rifle. The plus of the 338-300 ultramag is it can get you into the low end of the big 338 chamberings with very little expense to build and then to shoot with cheap brass. No way I would ever consider paying custom money for this chambering though. Just to many better choices that beat the pants off it.

 

[Pdvdh]

LTLR,

What are some of the other cartridges you prefer, albeit at a higher cost to build, load for, and shoot?

 

[B23]

Retumbo and 225 Accubonds have proven the most accurate so far in my 338-378 Accumark but I don't get near the FPS numbers that others here are reporting about. I get sticky bolt when I start getting much above 3275 with the 225's. I can get within 50fps of the 225's before I get a sticky bolt with the 250 Accubonds but so far the 225 out shoots them.

 

[RMulhern]

I bought a Weatherby ONCE......when I was young and dumb!

 

[canadianshooter]

I have since developed a new hunting load for my 338/378 Accumark which is 112.5 grain of Retumbo with the Barns 225 TTSX. This load shoots consistently in the .400" of an inch with an average velocity of 3191 fps at 68 degree F with a cold or hot barrel. I never heat my barrels to more than 130 degrees F which you can tell by being able to touch the barrel for about 1 second before you have to pull your hand off. I had initial problems with sticking cases which were caused by necks that were a few thousands of an inch over the limit of 2.913" I trimmed them back to 2.895" a bit shorter than recommended and things are back to normal. My other load is the Hornady 225 SSTs with the same powder load for the almost exact same velocity. This one does not shoot as well but is not far behind and is below 1 moa consistently and they both have the same point of impact. What I like about these 2 bullets is that their BC is almost identical at .514 and .515 which is literally the same as far as I'm concerned. I use the Hornadys for practice and the Barns TTSX for hunting. I use the Redding deluxe die set and neck size my cases only. My chamber is a really tight chamber for a factory gun which I'm sure helps my accuracy. This is pretty good for a stock rifle out of the box.
Can one buy something better? Most likely but at what cost and for what amount of accuracy improvement? Also for me the Weatherby stock fit me well and this one shoots fine for my intended use which is moose, elk, bear and caribou hunting at longer than usual distances. I like the look of the rifle as well. I would like to put a Huskamaw 5 by 20 on it in the future but that will have to wait as I'm a father with 2 small boys 8 months and 2 1/2 year old on a limited income. The Bushnell 6500 series 4.5 by 30 loses a lot of sharpness above 20X but does the job for now!

Guns are like woman, every man has different tastes!

 

[eaglesnester]

gun)gun)gun)I know this is an old post but I am going to add my two cents worth as there are a lot of us on here that shoot these rifles, Try 2 grains over max of RE-25 (107gr) for a MV of 3146. with 225gr TTSX (tipped) Good accurate load in ny gun shooting off a sturdy bench and 6-9inch Caldwell bipod with rear sandbag.Load your OAL as long as possible and still operate in the magazine. Load your shells carefully. I am getting 5 shot groups of .435" at 100 measured meters I have had this rifle pillar and skim bedded by Dave Jennings of Jennings outdoor sports in Pritchard B.C. Although I dont need it I also have a timney trigger on order that I am going to install in this gun; I dont see how it could possibly shoot any tighter. By the way I also have the NEAR single piece Triple ring mountinng system for my Leupold MKIV Long Range Tactactle 6.5X20-50MM with TMR recticles. The Near scope mounts bold to a Pictanney rail on the rifle. My groups seem to stay consistently tight These new tipped TTSX shoot like a house afire as they are a monolithic bullet of solid copper this could be the reason as they do not fly out of trajectory because of being ever so tiney out of balance. Thats my story and Iam sticken too it. Remember work up slow, I have spoken with the barnes people over the phone and the have reassured me that by carefully working up you can safely (most of the time) exceed their max recommend loads in their manual.
Cheers @ Tighter Groups: Eaglesnester

 

[ldvn12]

I purchased a weatherby accumark this year with a accubrake in 338-378.
Put on it a steiner military 5-25x56 scope.
I tried 185 Barnes TTSXBT bullets with 105 grains of reloader 25 shot 300 yd groups of 1.08". decided I wanted a heavier bullet so tried Barnes ttsxbt 210 grains and 100
grs of hogdgon hybrid 100v at 300 yds I got .375" 3 shot groups. Iam so happy with the groups I got with the 210 gr that I will never use anything else.
My rifle is now a tack driver as far as iam concerned.

 

[Ben Hall]

Did you end up getting 338/378 ?

 

[deadidarren]

I purchased a weatherby accumark this year with a accubrake in 338-378.
Put on it a steiner military 5-25x56 scope.
I tried 185 Barnes TTSXBT bullets with 105 grains of reloader 25 shot 300 yd groups of 1.08". decided I wanted a heavier bullet so tried Barnes ttsxbt 210 grains and 100
grs of hogdgon hybrid 100v at 300 yds I got .375" 3 shot groups. Iam so happy with the groups I got with the 210 gr that I will never use anything else.
My rifle is now a tack driver as far as iam concerned.

.125 moa better take that to a bench rest match

 

[Wachsmann]

here is my 2 cents...I had a 257 weatherby and I know its not a 338weth...Well mine shot the factory 115 at 3/4 inch 100yard groups. I tried several loads and never could get it to shoot better than the factory weatherby loads. It sound like the 338/378 is a larger case capacity but speed is not everything. I sold mine and got a savage 6.5x284 and it shot out of the box several different loads at 3/4 inch. I worked up a load with the 140VLD and its a 1/2 inch gun as long as I do my part. For me my next rifle will be a full custom rig. Honestly its what you want and yes its good to make an educated decision on things but if you know the product you will be getting or if you go with a fully custom rifle that will do everything you are wanting it to do then I would spend the extra doe and be happy. also weatherby brass is expensive to say the least..but its also getting hard to find the RUM brass as well. Also with a custom gun/caliber/case builder I would think they will have a proven load development recipe and have test fired in your gun with a target to prove it accuracy. This is what I would expect if I was laying down some large amounts of doe for a custom rifle. Also have the conversation of what your expectations are and what bullet you pan on running and I bet the builder will let you know weather it a good or bad option or what would be the best options to go with for as setup to what you are tring to achieve.. Not dogging the weatherby but its still a factory rifle just a high end factory rifle....just like my rem 300 ultra sender. Still a factory rifle but I had it bedded, trigger job done, and a muzzle break. Last load I was tring was shooting below .5 inch. I just need not to go and streatch out its legs and see what it will do. I might do that today... good luck...

 

[Warbird782]

My Accumark seems to shoot fairly well for a factory rifle. I am shooting 300 grain Nosler Accubonds on top of 92 grains of IMR 7828 SSC.