300 Win Mag Vs 30-338
What are the pro's and con's (if any) between these two rounds. I have been told that the 30-338 is more efficient and may have a tad more accuracy potential, albeit slightly slower. Probably a moot point since I am having a 30-338 built, but I was curious if there was a consensus one way or the other. My goal is a long range hunting and target (500 yards routine, 1000 yards occasionally) rifle.
Last edited by CWPINST; 03-12-2008 at 08:18 PM.
No personal experience with the 30-338, but I would expect your case capacity to be a little less, so probably a little less velocity. You will end up with a longer neck though, and that is one thing that always bugged me about the Win Mag.
Originally Posted by CWPINST
One case you have to make the other you can buy. Anything else would be just academical.
300 win mag
The shorter neck on the WIN MAG means NOTHING!Everything is availible for the WinMag with out paying for custom,plus you have a nice selection of brass.The Win Mag is every bit as accurate as a 30-338!
i had a custom 30-338, it was a great cartridge, and it was right on the heals of the 300wm. very accurate, but i have had several win mags, and i favor them. more velocity extremely accurate, and good ol lapua brass. br
It sounds like you are already committed to the 30-338 and it is a VERY GOOD cartridge so don't feel like you'll be handicapped in any way. In its day it was one of the better long range cartridges. (As were all of the other short [2.5"] 30 caliber wildcats of the 50s and 60s.)
The 30-338 virtually duplicates the 308 Norma Mag and if the Norma had not already existed I'll bet the 300 Win Mag would have looked exactly like the wildcat 30-338.
One good way to improve on the 300 Win Mag is by making it into a long-neck wildcat. Several noted long range shooters did this back in the 60s and 70s and it won more than its share of fake wood including one National title. You simply ran a 300 Weatherby case (or 340 WBY) into a FL 300 Win Mag die and, voila, a winner every time.
Of course, at one time, the straight 300 Win Mag was considered to be one of the best long range cartridges there ever was. But is has become old fashioned and not chic and sleek enough for todays shooters.
I still can't get over this group
Originally Posted by matthew dienes
If Matt says the .300WM is accurate, it is and you better believe it.
Last edited by PPP MMM; 03-13-2008 at 05:12 PM.
I have a custom built 1000 yard rifle chambered in .30-338. It shoots as good as any 300 Win that I have seen. Brass is not a problem at all,as a matter of fact, you can get Norma brass in .308 Norma magnum. The two cartridges are so close in size that all one needs to do is trim the Norma case length to the 30-338 spec and run the through case through the size die. When I first started reloading for the 30-338, I wanted to eliminate the short shoulder length that is typical of all belted cartridges, so I used 300 Win brass. Using the 308 Norma brass is a LOT less work. One could also opt for the 308 Norma chambering instead. If I had it to do over, I would probably opt for a chambering using a beltless case, such as a shortened Ultramag. when the Ultramag first came out, some folks discovered that quality brass was available from European manufacturers. RWS comes to mind. I believe there are others. "JayIdaho" is the one that brought this to my attention.
As for the various 300 magnum cartridges, any of them are plenty fast enough and accuracy is exceptional. I see no reason to re-invent the wheel by going for a widcat. Wildcats have less resale appeal than standardized chamberings. That said, build what you want and never look back. All accurate rifles are a joy!!!
You have made a good choice. I used the .30-338 for 1000-yard High-Power competition for quite a few years. I started using it because the Army Marksmanship Unit used it from the late 1960’s up through the time I was at Fort Benning (in the early 1970’s), and it can shoot just fine. I still have a .30-338 that I had built for long-range hunting. BTW: If your gun is under 12-pounds, get yourself a good muzzle brake… you’ll be glad you did.
Regarding loads, this was a bit of a problem. The .30-338 shoots the 190gr MatchKing as well, or better, than any caliber I know of. The 66gr IMR-4350, Fed-215M primer, under a Sierra 190gr MatchKing is well known for the number of times it won the Wimbledon and Leech Cup matches. Problem is, the 190gr MatchKing is not particularly well suited as a game bullet. The jacket is hard, and at ranges over 800 yards, sometimes it does not open up too well (unless you hit bone). I tried several of the 200gr game bullet offerings, but they just couldn’t hold a candle to the performance of the 190gr MatchKing. Eventually, I got around this by using a 1-11” twist barrel when my original barrel began to show serious throat erosion. This worked great! I found that I could shoot any of the 200gr match bullets as well as the 190gr MK, and the 200gr SBT GameKing bullet also shot very well.
It has only been recently, with Hornady’s 180gr Interbond bullet, that I found the best combination for my gun. Using H-4831 SC (the load is listed in the Sierra 5th Edition manual), I can get this bullet going at 3000fps, with 200-yard groups that are routinely under one-inch. For hunting, I zero the rifle at 300-yards, so anything out to 400 yards requires no correction at all… just put the crosshairs on what needs shooting (anywhere under 400 yards) and shoot. Now the bench rester’s will probably beat on me with a solid-aluminum “heavy-gun” stock, for not doing a bunch of elevation adjustments and wind calculations (they would get even crankier if they knew I was using a Nightforce 8-32x NXS with an NP-1RR reticule that must have been designed for the 30-338/180gr Interbond combination). But for a hunter this is ideal for those shots that develop in a hurry.
Now, regarding the generally accepted horror of making 30-338 brass… what a crock of pure CRAP! The guys doing all of the moaning have obviously never done it. I have made well over a two thousand pieces of 30-338 brass, and it is no more difficult than doing PROPERLY prepared .308 match brass. Here is my procedure: start with .338 Winchester Magnum brass (I prefer Winchester). Full-length resize a well lubricated case (Imperial resizing lub is the best I have used for this job) in the standard .30-338 FL sizing die (with the decapping/neck expanding button in place). Clean the brass and turn the necks. Check your chamber’s neck diameter. I like to have the necks on my finished (loaded) rounds .005” under the chamber’s neck diameter. I turn my brass accordingly. Next I deburr and inspect the flash holes and true-up the primer pockets. Now, trim the cases to 2.5”, chamfer, clean one last time, and inspect. You may have noticed that there is not one additional step… only the standard preparation necessary for any target ammunition.
You should feel confident that you have made a good choice in a long-range hunting rifle for your chosen conditions. In the thirty-odd years I’ve been using one, and I have tried and owned several others, I have not found a better 1000-yard deer rifle that can be carried (not carted) into the field.
By now you have had the chance to evaluate your own 30-338, its a hack of a cartridge, mine was built on a p-14 enfield action and it regularly outshoots the newest whiz bang at the ranges, I can at will hit gongs out at 5&6 hundred yards. Just to say welcome to the group of old cartridge big bore shooters, 67.5 grains of IMR 4831 behind a 180 grn sierra boat tale.
Originally Posted by CWPINST
greetings, hello everyone. first post.
this is an old thread but worth reviving, I was compelled to reply.
a few weeks ago I lucked into an early Weatherby-built FN Mauser, action stamped 1951, rifle built in 1952 (I asked Weatherby using serial ##) with a box of ammo.
price- a princely $400. no one wanted the gun, it was missing the buttplate, was d/t with mount bases, but no scope or rings.
a gun with no sights or buttplate, is like trying to sell a house with no front door, or a car with plastic taped over a side window. it will be a hard sell in today's nitpicky consumer market.
but I didn't care. being old school, I look for hidden potential, not curtain dressing and advertising glitz.
the action is butter smooth, the bore a mirror. receiver plainly marked "Weatherby South Gate, Ca"
it has an early 3 digit serial number. Weatherby used Mauser actions until he invented the Mark V in the late 1950's.
it is one of the first 1000 rifles Weatherby made, when he started the business after WWII.
the ammo box was handwritten pen marked "300 H&H Wildcat"- and basically it is chambered for 30-338.
back in the days before the 338 Win Mag was introduced, this round was first known as the "30 belted newton"
I also have an old Mauser custom barrel stamped and marked "30 H&H Newton" for the same round.
it later became known as the 30/338. The ammo I got for it is headstamped 300 H&H, obviously trimmed brass.
anyway, last night I loaded 20 more rounds of ammo for it. it was too easy.
all I did, was take once fired 338 Win Mag brass, and neck size it, in a universal 300 Magnum neck sizing die.
this die will neck size any belted 300 magnum, Weatherby-Winchester-Norma, or any of the mid-century "short magnums" that had a 2.5" case approx.
no need to full length resize. just get used or new 338 Win Mag brass, and neck size it.
FWIW, a 300 Win Mag won't chamber in this rifle- of course- because the shoulder it much higher, and the brass much longer
Neither will a 308 Norma Mag round chamber in the rifle, the shoulder is just a tad too high on the case. like .010" - if that- too high. it will go in, but bolt won't close downward.
if you did use 308 Norma brass, you would have to full length resize to push the shoulder back a bit.
but you don't have to FL resize 338 Win Mag brass. that brass is a drop in. Actually, you can take fired 338 brass, and chamber it in the gun.
once I was able to do that, realized 338 brass was the ticket for a 2.5" belted short mag 30 caliber, neck it down.
necking down is a lot easier than necking up 7mm Rem Mag brass.
it's also a lot easier than trimming a lot of 300 HH, 300 Weatherby, 300 Win Mag brass- trimming a lot of cases can be a PITA after a while
the 338 case is ready to go, just neck it down, and go.
the only downside is, the headstamp is 338 mag.
FWIW I used 300 Mashburn Short Magnum load data, from Ackley's Shooters/Reloaders book Vol. 1 (1962).
there were many of these early short mag wildcats from various makers, back in the 1930-40-50's.
the load data for all of them is interchangeable, providing it's approx. 2.5" to 2.560" case length and 30 cal.
I loaded 70 grains of 4831, with a 150 grain GameKing bullet. at 70 grains the necked down case was full, to the bottom of the neck,
perfect full case, with the neck space left open for the bullet to seat.
the Mashburn load data says 3350 fps for that load and bullet weight.
Last edited by locknloadnow; 07-24-2016 at 08:27 AM.