Whaddaya think? Discuss among yourselves.

WOT=waste of time

Pissing in the wind? If you have good boots, etc, there's nothing 'wrong' with it. Like the 9.3 Barsness-Sisk, you can have your own deal, with all the costs that go along with it. Novelty aside, a low power 338 is short action is already covered with the 338 Fed. And it's hard to beat the 338-06 for the same level of power as your wildcat, or a hair better, by the time you lose all that powder space to bullets in the SAUM case. If you build it on a std length action, you'll better the 338-06 by a hair, but you might as well keep the mag bolt face, the same cart length, and get real power in the 338 Win Mag.

I hope you get the picture. It is a lot of money and hassle for almost as much as what is relatively common and cheap.

A 338 Whizzum on a 3" COAL receiver,throated for 250 Scenars would crack corn..................

This is a picture of a 308 (same length as a 300 SAUM case) with bullets shown to the 2.950 OAL that Accurate Mag's WSM magazives will run. 2.990 is the room present, so there's .040 left on the table here. The SAUM's neck is actually .008 longer than the .308, if we're being really particular.

From left to right:
250 Berger Elite Hunter, 210 TTSX, 225 AB

Ultimately, 338 RCM already has this ground plowed. But for the sake of visualization...

A 338 Whizzum on a 3" COAL receiver,throated for 250 Scenars would crack corn..................

Who has a 338 RCM? I forgot about that one. Maybe it has a similar capacity to a SAUM case. It's easy to forget about the RCM's. I'm planning on doing it again in just a moment.

I loves me some Whizzum brass................

I have two 338 RCMs. The brass is very similar to the 7 SAUM. Both will fit past the feed rails on most rifles with no modifications.

I would have used the WSM but didn't want to alter the two rifles I used. Just like the RUM cases not all rifles will allow a WSM get past the feed rails.

22" barrel 338 RCM 61 gr of RL-17 225 accubond 2750 fps

30" barrel long throated 338 RCM in LA 56 gr RL-17 300 gr Berger hybrid 2550 fps

Tough to trump the humor of a 30"!................

Azshooter, Remington has made dedicated RSAUM magazine followers, but their present Q.C. problems precludes me from buying one of these as a donor left hand rifle. My Mauser test beds seem to do O.K. using the old military followers, and some rail work, along with the magnum bolt faces. I can later do any standard length belted or Ruger Magnums by using new commercial barrels. Right now I'm using old, freeby, military stepped barrels, with a couple of barrel threads trimmed off. With the elongated, by case tapering, 300 RCM at ( 53.94mm) C.O.L. I've cleaned up the old chambers' shoulders, leaving their necks and throats alone.

What do you think is possible with my 72 gr. capacity 7.92 version? With my "Schuleresque" case taper, I'm really close to your shorter 338 RCM's capacity. This old barrel is 21.5 inches long, with a shop made muzzle brake, screwed on, for about 24 inches total length.

On your long action with that 27 inch barrel, you might re-chamber the RCM to a full length 338 x 375 Ruger wildcat. This will nip at the heels of my 26 inch barreled 338 R.U.M. I have a couple of these Ruger/Schuler knockoffs, in a 8mm and in a .416 caliber. FWIW, even with my exaggerated case body taper, I have exactly the same case capacity as the 1/10th of an inch shorter, 2.5 inch long 416 Newton Wildcat.

With these Ruger parented designs, you can pick up quite a bit of capacity, just by building them in full length 375 H&H pattern actions. Personally, I'm happy to stick with my 66mm long, 8mm Ruger/Schuler knockoff, using 200 gr. Speer Hot Cores.

The real McCoy, which is the 8mm x 68mm S Schuler, is still really popular in the Horn of Africa, but Hillary's goons at State, have so far, choked off our Euro supplied ammunition for it. So, I simply "Americanized" it, to kick some sand into their faces.

My 416 is reamed with this same 8mm PT&G finish reamer, using an oversized pilot bushing. Then my G.S. did my 2 R chamber using his own set of neck throat reamers. With my case taper, my .416 wildcat is the largest bore I will try, with this finish reamer, and its companion PT&G GO gauge.

You can do about the same thing. Your stock 300/338 RCM's can be necked up to .429 to make short fat, and rimless, 444 Marlins on steroids. My short RCM parented wildcats have 26 degree shoulders and are .495" at their shoulders. Your cases have 30 degree shoulders and are a little over a half inch in diameter, at theirs.

So the Hornady 265 gr. Flex Tip bullets can be juiced up to the top of their working range, in a bolt action rifle. At least the dummies I made up with my unique case body taper, fed fine out of my M-98's box magazine.

My earlier 44 x 356BB wildcat is in a Post 64, T.E. Win. M-94 carbine, and also clearly fulfills the Seahawks' motto of "The Legion of Boom", with these 'gummie tips'. The difference here is between the capacities of the 300 Savage, vs. the 30 Gibbs, with both ratcheted up to 44 caliber.

My Winchester carbine has a re-cut 30-30 bbl., with a 1 in 20 twist, and it stabilizes both these Gummies and my own custom 316 gr. cast S.W.C. bullets, out beyond 300 yards. But with either of these bullets, recoil becomes really fierce at the high power end.

For sure. Especially in the hands of a troll, fresh from under a bridge.

The 30" barrel was a concept I wanted to try. I wanted a LR shooting rig that would be similar to a F class rifle. While I did take this 13 lb rifle on one coues wt hunt were we glass and shoot from longer distances, the main idea was to shoot a high BC bullet at slow velocities. It allows for up to 10 rounds in a row without the barrel getting hot which is an issue in the Az summers. Recoil is very manageable and fouling is reduced with such slow velocities.

The concept works. BC of the 300 gr Berger is .818 with excellent accuracy. Retained energy is amazing. 3000 ft/lb at 575 yds. Wind drift 8.7" at 500 yd with 10 mph crosswind.

I have the usual stable of regular rifles with some shooting bullets in the 3500 fps or higher catagory. I wanted to try something different. Go ahead and mock me I don't give a crap. I enjoyed making this rifle and like shooting it.

Azshooter, that's a neat concept, but I have to wonder if your bullets are spinning fast enough to open up in Big Game. Hornady techs told me I needed to use a one in ten or one in eleven twist with my 416 wildcat cartridge to use their 450 gr. B.T. Spitzer, target bullet, at 2200 fps. Standard twist is one in fourteen.

Have you checked out your terminal ballistics in phone books or something similar? Since you are close to the old 338 x 06, there should be some data already out there, for a max range, to kill something with it. The reason I asked for some help is that about the only data I have for my 7.92 x 300 RCM is for the old 8 x 68 Schulers' 220 gr. bullets at 2900 fps. I'm stuck with using about 20% less powder, in the RCM parented wildcat. And I'm using a shorter barrel, with the military Mauser's free bore.

Ray Speer once told me that his bullets would never lose more that 8% of their spin, even at extreme ranges. With quicker twists, this retained angular energy comprises about 10 to 13% of the linear velocity/energy of most bullets.

I'm just happy to hear from someone else who is working with these RCM's in custom builds, without butchering their actions.

SquatToPee,

It's your Imagination,Pretend with it as you must.

A 22-incher soundly whipped your Dumb Ass.

Congratulations?!?..............

Stupid ain't a "concept"...it's a Plight. Them differences are stark.

Hint.................

That is one sharp rifle. Don't throw it down in the gravel or spray paint it with some psycho-delic ratttle can paint, only a stupid SOB would do that.

SquatToPee,

The humor of you doing your best,via Estrogen fueled rant,is epic.

Thanks!...................

Twist is 1 in 9.5, velocity is 2550 fps. RPM is 193,263. It did a number on the small bodied coues wt. It had an exit as would be expected with a 300 gr bullet. The low impact at 400 yds didn't ruin any meat to speak of compared to what my 257 did with 115s running over 3600 fps.

It is the target bullet. I could switch to the hunting version when I run out.

I read in F&S,that the 257 Roy squirting X's,is rather steak friendly...despite their 3750fps launch.

Bullets matter more than headstamps.

Hint.....................

Somebody correct me if I'm wrong, isn't that G1 bc based on a much higher launch speed than 2,550?

Not saying it's not an awesome bullet just seems a little optimistic.


Mike

Oh there's more than a few dropped balls and unconnected dots..................(grin)

The long throated 338 RCM with 300 Bergers using the G7 of .419 matches the suggested comeups using JBM's program.

I am not suggesting this rifle is THE LR big game hunting round. I built it so I could shoot multiple shots whether at the range, shooting rocks or jackrabbits in hot weather. Also wanted the fouling to be minimal and barrel life to be long. So many of our hotrod rounds require rebarreling why not make a rifle that lasts like a 308?

Stupid is never smart.

Hint................