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338/378 wby vs 338LM

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Unread 05-09-2009, 11:08 PM
Platinum Member
Join Date: Jul 2004
Location: Texas
Posts: 6,881
Re: 338/378 wby vs 338LM

Originally Posted by PFCSkoug View Post
Thats just how it got explained to me by a VERY reputable gunsmith. i would rather not drop names but just believe me that hes well respected

I'm am not piling on so don,t take it that way.

Every good gunsmith has his preferences on actions, barrels,cartrige type (Belted,rimed,rebated
Etc) based on personal experience and the type of weapon he choses to specialize in.

I have tried many types of actions and cartriges and came to this conclusion after building

For years I though that to make an accurate rifle I had to use ether a remingtion or a
mauser action because thats what I had the best luck with.

But once I learned that every action had to be treated a little different in order to make it perform I was very suprised and pleased to find out that the problem was ME.

In order for a rifle to shoot well a lot of things have to come together (To many to list)
so as an apprentice gunsmith you need to keep an open mind and you will learn a lot

I use to be a Remingtion guy and thats all I wanted to build on, but I kept seeing those
MK 5 actions and reading about how strong they were but were not suposed to shoot
because of the Freebore,belted cases and the double radius.

The belted cases were all the rage when they first came out and if you didn't own one
you didn't have a magnum.

And as far as freebore most of the new powerful magnums like the RUMs have lots of it
to increse velocity without excessive pressure.

So when I decided to build a power house on a Weatherby MK5 action I chose the 30/378
cartrige (With all of the supposed bad things) and was I shocked.

This thing shot so well that I though it was just luck and had to build more on the same
action and cartrige design.

The 30/378 shot a five shot group of .092 (Less than 1/10 of an inch) with a 200gr NPT at
over 3400ft/sec and all subsequent builds have been under 1/4 MOA Rifles.

I own 4 rifles that will consistantly shoot under 1/10 of an inch and two are on remingtions
and the other two are on weatherby actions.

I hope you were not offended because It was not entended that way, only to show that there
nothing wrong with an opinion as long as it doer not cloud your perspective.

As a new gunsmith try to make every rifle shoot well and you will be the guy that others are talking about.

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Unread 05-10-2009, 07:12 AM
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Join Date: Jun 2006
Location: Wyoming
Posts: 530
Re: 338/378 wby vs 338LM

I had a Weatherby Accumark 338/378 for awhile. It shot excellent with both foctory and handloaded ammo. It was a very nice rifle, but I didn't care for the action. I would probably choose the Lapua, but I don't know if I would go with the Remington. I know there are some people perfectly happy with them, but I have sure heard a lot of bad. Not to mention the short barrel. I would look into an Armalite over a Remington.

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Unread 05-11-2009, 10:35 AM
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Join Date: Feb 2008
Location: Eastern Iowa
Posts: 25
Re: 338/378 wby vs 338LM

Absolutely no offense taken JE. That's the great thing about this business, everybody has there own opinions on what works best and well as the customers they try to serve. I agree with you 100% that any action can be made to shoot if you treat it like it wants to be treated.

I personally am not the biggest fan of the Weatherby line of rounds, but that doesnt mean there bad persay (odviously ive pointed out the flaws "I" see in the design) but that by no means says that they cant or wont ever shoot good. Heck they worked out really well for Roy Weatherby, and who am i to argue with a guy like Elmer Keith (helped develop the 338-378)

Nathan Skoug
Gunsmithing Student
Trinidad State Junior College
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Unread 05-13-2009, 01:32 AM
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Join Date: Mar 2002
Location: Wyoming
Posts: 2,612
Re: 338/378 wby vs 338LM

J E has an exceptional point. I have built rifles for 35 years on all kinds of actions and currently own excellent shooters on virtually every action out there. Like J E said they all can be made to shoot very well if the guy knows how to work on that particular set up. The remington action is the most mass produced action in the world with the most aftermarket parts and the primary action most gunsmith schools teach on. So remington gets the most talk because that is what most smiths are familiar with. I have heard them badmouth the crap out of wby's for 35 years because they don't know how to work with the wby's and want to hold onto there customers. For 60 years the gun world has been chasing weatherby's and trying to compare to a weatherby. There are a lot of smart guys out there who figure if everybody's been comparing everything to wby for 60 years then I will just get a weatherby.

Now for your question. The weatherby mk 5 action is the best commercially produced action available for the big 338's. It is the only one designed for such cartridges with a great trigger while the others tried to make there action fit the big cases and are just not a good fit. Need mods for feeding, etc, particularly with the long 300 grain long range bullets. There is absolutely no comparison to any remington in a big 338 caliber to a 338-378 weatherby accumark rifle. Do you want a cheap imitation or a Weatherby. If you are going to shoot a big 338 then get a custom action or a mk 5 action that is designed to hold it. I am just not comfortable with putting Lapua's or 378 case cartridges on a remington 700. I know guys do it but I am a retired engineer and not me.

During those same 35 years I have heard all the baloney about wby's. Freebore doesn't shoot straight, all nine lugs won't match up and they can't possibly shoot straight, the double radius shoulder doesn't shoot straight, the brass is no good, etc, etc. All of this is pure horse malarkey. I own wby's in every caliber except the 460 and they are by far the most accurate, hardest hitting rounds on average through the years of anything I have ever shot and I have built about everything in about every popular caliber and many not so popular ones. I have all kinds but consistently my go to rifles for that super trophy hunt for some reason have always been wby's.

Don't read this and think I am a wby fanatic. I have no affiliation with wby. I am just stating facts I have come to know about wby rifles. They are fantastic rifles and calibers and what everything else has been compared to for 60 years. Again any action can be made to shoot straight but there are other factors to consider.

From my experience if you are looking at a factory big 338 I would get a wby accumark 340 or 338-378. The Lapua is also a great round and I have two 338 lapuas that shoot great and are built on wby mk 5 actions. Also had a couple of sako trg's in 338 lapua that I sold. It is a little slower than the 338-378 but an animal will never notice the difference. The only difference would be the slight edge in trajectory/wind the 338-378 gives you. They are both very accurate and I have never noticed through the years one being more accurate than the other because of norma or lapua brass. Brass is what you make it during case prep and if you do that right any brass will shoot very well. Some you may have a few more discards with during the preperation process or some may not last as long. But it amazes me to find out now that through all those years of tack driving groups and numerous B&C trophies, with many taken at extremely long range, that my old wby brass was no good. If anybody has some of that worthless old wby brass and needs to give it to somebody please send it to me.

Again I am not a wby fanatic and the point of this whole essay is to not let anyone talk you out of any rifle by bad mouthing it saying it is not accurate. If people got on here bad mouthing sako or something I would have talked about all my great shooting sakos for example. They all can be very accurate. If you want the extra power of the 338-378 it will be just as accurate as any of them. I have seven of them and anyone is welcome to see them shoot. Most people want one when they do.
Predictions are difficult, especially when they involve the future
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Unread 05-13-2009, 10:48 AM
436 436 is offline
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Join Date: Mar 2009
Location: NorthWest
Posts: 648
Re: 338/378 wby vs 338LM


As to your post;

Iím a 40 year Weatherby rifle user, Iíve used most all their calibers {257 Wby being my favorite} and all I can add too your post is;Ö.
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Unread 05-13-2009, 09:32 PM
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Join Date: Dec 2008
Posts: 868
Re: 338/378 wby vs 338LM

I always thought whby made great brass. I have 2- 257's have loaded several times with no problems.
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Unread 05-15-2009, 08:22 AM
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Join Date: Sep 2005
Location: Kalifornicated
Posts: 383
Re: 338/378 wby vs 338LM

Wby brass is pretty good brass, it is just a little soft and if you are hot rodding them....they die in 5-7 firings.
USMC Scout Sniper 88-94
Instructor 1st. Mar. Div. SS school 91-94
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