Home Forums Hunting & Shooting Ask The Gunwriters Weatherby .338 RPM

As much as I hate them , that beast will have to be braked.

I hope it does well. Be cool to see some folks making brass other than Wby for them, but even then, It should be a handy rifle that allows 5 rounds in the gun. Be a great cartridge to build around.

Check out the Back Country podcast with JVB in March of 2022. He interviewed Adam Weatherby about the cartridge and it has me interested. It is very close to a 338 WM performance with <250 grain bullets and under. Holding 4+1 cartridges is a plus but the comments Adam made about it performing very well down to an 18” barrel length is what got me excited. It’s a very efficient cartridge and it sounds like they are embracing the short-er barrel craze for the suppressor market. I have a 36M can in jail and this could be a sweet pairing if Weatherby comes out with a Backcountry 2.0 Carbon Ti with an 18-20” barrel.

If I remember correctly, a 338-06 holds 67 grains of water, a 338 WM 86, and the 338 RPM 82.6.

I'm in the 4th quarter as far as time left hunting but if I were younger.........can't have too many 338s even though an 06 probably does all I could ever need. Come to think of it can't have too many 06s either.

I want one in the Vanguard with $8 a box ammo ( 210TTSX) and $25/Bag of 100 Huntington brass! (Never hurts to dream!)

There is actually a fair amount of Weatherby ammo around. There was 40 or 50 boxes of 6.5 RPM at the guns shop today. I see a lot of 7mm Wby mag and 270 WBY mag (not many people shooting them anymore). All ammo is going to run $90 a box soon.

Eggzackly

Somebody asked why anyone would want a 338 RPM.

I have a Win 670 in 30-06 that someone gave me. I have no use for a 30-06. But the 338 RPM fits that bolt face.

a 338 RPM with an 18" bbl and a 230gr ELD-X has
1660 ft-lb at 800 yd with 1800 fps velocity
1310 ft-lb at 1000 yd with 1600 fps velocity

and it gives me something to do with an, otherwise, throw away gifted 30-06.

FB Bob - You can throw that ‘06 my way, Ha
Welcome to the fire, the Lunacy begins here

I’m not familiar with the 670, but it sounds like a fun project . CRF or PushFeed ?

Does the magazine length support a little long-throating ?
Recent 338s often seem to be short throated to accommodate the long ogive 33 bullets within their magazine length restrictions.
(338 RCM, 33 Nosler, RUM ) The RPM didn’t have a shorter case from the 6.5.

Keep us posted please

Ruger screwed the pooch by not marketing and advertising their 338RCM properly. Shortly after it flopped they discontinued it. Ruger peaves me and at times I can't stand them but dang I love my lefty Hawkeye 338RCM. Love that thing. But at this moment I wouldn't count on Ruger to make a proper rifle or anything other than an cheap Ruger American junk or their little LCP.

It ballistically looks like what we're all trying to get out of our 338-06's, but never can.

Good luck with that idea.

I'll just stick with my 338-06.

Like the idea of the chambering, I’ll continue to use my 338 wm like I have for 30 years

Never again will I buy a rifle chambered in a cartridge with a rebated rim. I just spent a couple of days resolving a feeding problem with a WSM when the left hand cartridges in the magazine climb the feed ramp and the bolt slips over the rebated rim into the extracter groove. Give me the .338 RCM or 6.5 PRC designed cases or even the .338 Win Mag. any day without rebated rims! And in a .338 when you might use it on bears up close, a feeding problem due to a rebated rim is the last thing I want.

That sounds about right. The 338-06 Ackley holds 72.6gr. full up.

It's great there are new things being developed. I get it. New & exciting stuff keeps the ledger in the black. Keepin' up with the Jones's & all that. Call me contrary, but this Weatherby thing gets a big yawn & the oddball proprietary brass kills it right there for me. Especially after the spotty availability of just about anything during this scamdemic clustercoitus of the last 2 1/2 years. They had a perfectly workable middle of the road 338 with the A-Square-06. Will anything hit square in the boiler room with the RPM know the difference from the A-Square? Maybe that extra few yards of point blank range will make hits easier?

The crusty old curmudgeon also fails to understand the race to the bottom everybody's engaged in with super-duper short barrel lightweight rifles with fair to middlin' heavier hitting cartridges... then braking them. It seems some folks have more $$ than sense, but hey I kinda get it. I guess going deaf beats having a bunch of halfmoon scars on your forehead. Mine's littler than yours & is obnoxiously loud, spits fireballs, & bites doesn't strike me as a very positive statement. Isn't there a point of diminishing returns in regards to light weight? I cant imagine these leichte Wunderwaffen point & hold nearly as well as something weighing a couple of #s more. If 2 or 3 #s is that important, maybe lose it from your belly rather than the rifle. Flame suit is hanging in the closet, but I really dont care.

My 338-06 Ackley, built before there was a factory 35 Whelen, gets an honest 3000fps & under 1" groups with 200-215s using plain old 30-06 brass & 4350... a few fps less with Big Game. Brass life is very good. The 25" barrel drives the all-up-ready-to-hunt weight to a whopping 8 3/4 #s with 5 rds of ammunition, add a sling we're talking a hideous 9#s. No brake is needed, but maybe a gun-bearer. Just for giggles, I'll try some 225s to see what it will do with them. Thinking 2800fps will be easy.

I like that Weatherby is developing a really good middlebore but I'm not convinced about the related rim. I'm already set up with 2 338win mags and the shorter 338RCM. The Weatherby 338 basically duplicates my 338RCM. Basically decent performance from an short action short barrel rifle.

I don't know how it will pan out but I'm also of the opinions that the RCM Ruger case and old 338 win mag case are probably less problematic in the long run. Still I like the shine the middlebore is getting.

Old pine,

I'd be interested in what lightweight rifles the 338 rpm will be chambered in.

I agree on the marketing failures with the 338 RCM. I own every flavor of factory ammo they ever offered. From a 20" barrel, the 338 chronographs 2650 fps with 225 grainers. That is the same velocity as the 338 win mag shooting 250 grainers from a 20" barrel.

Talk to any serious goat hunter up here in Alaska, about how critical it is to anchor these big brutes. Occasionally, the big ones will take multiple fatal hits, then launch off a vertical cliff.

A rapidly expanding 225 grain interbond, fusion or accubond would be an excellent choice.

Anyhow, though I fully support the 338 RPM development, the 338 RCM carbine was the greatest gift to Alaskans who hunt steep terrain. It was an even greater gift to South-paw Alaskans. Those poor bastards get no flavor in their bolt actions. Usually just meat n potato cartridges, with no seasonings.

I will stick with my 338-06 also.

I think the rifles will be snazzy for lightweight use or weight nut some are going to be pricey. The deal breaker may be if there's support for the case component and I'm not overly hip to the related rim. Still one has to give Weatheby props for giving some shine to the middlebores and a true game performer.

I suppose once I'm out of 338RCM cases I'll have to form some from 375 Ruger or some of the PRC brass. Something I've not done.

The only th8ngs I've smashed with 338RCM in lower 48 is elkband black bear but they aren't the toughest. There are grizzlies in some of the areas I go to and it's pretty thick so the short handy 338 is welcome but so far that's just been theory though the ability to go scoped to irons in the field is awesome.