Home Forums Hunting & Shooting Hunting Rifles Ruger 338 rcm: 4 rounds down mod

Hi all,

I figured a way to fit 4 rounds down in the 338 rcm:

The rifle would fit 4 rounds in the mag, but bolt wouldnt close, due to the ejector needing space to articulate down into the magazine when the bolt is closed.

Since the case has very little taper, the magazine follower has very little taper. I simply flipped the follower around. Now, the ejector side was left open so that you could close the bolt. It was tight. I had to file a bit off the bottom of the follower and those raised portions of the inside of the floor plate.

I also had to flush-file off the excessive material of the trigger guard that holds the magazine box in place, so that the follower could articulate downward in the magazine without catching up.

Bam.......4 rounds down.



This is not possible with my 416 ruger, as the magazine box is much narrower. They probably did this to keep the wood thicker to handle the extra recoil.

Like most everything Ruger, brain cells weren't used during final fitment and finish. Had they gone this route to begin with, they would've had that 4th round down advantage over the wsm's, rather than blowing smoke about the "proprietary powders" and equal velocity to the 338 win mag, which was bullsht.

Could you post a pic or two of your modifications?

My mod was a laminated stock that let me move the floorplate down a little, with acraglas to fill the gap between the mag box and the floorplate assy.

That is some good news. Glad you figured it out it has always been so close to being able to do it.

Probably my favorite cartridge.

Su35,
I like the cartridge too. They are absurdly accurate. I thought I was hot sht with 1/4" groups. My friend, who put 20 years in the Army as a sniper, stomped my a s s with a one hole group from his 338 rcm carbine.

100% of my Alaskan hunting has been with standard medium bore carbines using low power variable or fixed scopes: 358 winchester, 9.3x62 mauser and 41 caliber wildcat off the 9.3x62 mauser.

I've had some of the most boring field results: caribou and moose exactly where i shot them. Not 20-60 seconds later in a swamp or in the river. Never any blood shot mess either.

The 338 rcm was one of those turn-key guns that required no expensive modification. I'm ok with 338-06 power, but I'm not ok with a 3 down 338-06.

As a 220 lb man, I have zero use for a 5lb-6lb rifle. The 338 rcm is plenty light and proper weight for meaningful shooting sessions with 225 grain full power loads.

225 grain for winter caribou or sheep in the mountains, sighted to the scope in quick release rings

275 grain swift a-frame sighted to the open sights.

Drop the scope and hike out with the 275 grainers in the belly.

A turn key mountain rifle in bear country.

Mainer,
I too would love to see pictures of what you ground down. I have two 338RCMs and will like do the mod too.

The Ruger compact rifle is my favorite bolt action hunting rifle and im fondnof that 338RCM. A real handy and powerful stick with irons and optic with 4 rounds. Sounds like a killer diller.

With my .340 Wby Accumark and my .375 Wby DGR, I ordered from Wby extra-capacity drop-down mags, so that I could put four down. Ruger doesn't have that?

If you look closely, you can seen the extra bulge below the normal mags:

That bulge looks a lot like a moose.

The moose was just sleepy. Thought I would get a pic with the mag thingy before he woke up.

Just wondering why theres a bipod on the DGR? Does this change the handling and feel/balance of the rifle substantially? And i can envision this being a catch-all in the entanglement of brush. I know even scopes can be a hook and catch piece for brush.

BTW that a big moose.

Yes, they are and I have never had an inaccurate 338 cartridge. The caliber is inherently accurate.

The cartridge is more of a 338-06 Improved in my estimation.

I have the 22" barrel SS Ruger version with a Meopta 6x42 on top. The lines on the Ruger really fit me well and recoil is a total nonissue for me. .......It has become my elk rifle here in AZ.

I am sure glad to see that 4 can go down.

I am burning 61.5 grains of RL17 behind a 225 AB for 2,780 mv. That touches the heels of the 338 win mag. Not bad for a 22" barrel. Much handier rifle in the thick than longer magnum smoke poles and yet has some long legs to it.

My hike out load is 61.0 grains of RL16 behind a 250 NP that fetches me 2,600 mv. I did get some 300 AB's to test out but haven't yet. I'll have to check out your 275 load.

I'm hoping to give moose and caribou a visit in AK this fall, well see. This will be the rifle that goes with me.

( I also have the same version Ruger SS 22" in 9.3x62) a converted '06.

Your .41 cal wildcat sounds interesting.

Again, thanks for your input.

This compact 338RCM is my elk rifle. I really get the "why" in the reason Mainer in Alaska likes this setup. Its has enough reach to be sheep and mountain game worthy. Its moderaty light and very packable and good handling. The fact that it has an optic and can go back to primitive irons is a big deal for him in a landscape where more often than not your in a remote location and even when it gets wet rainy or in the thick bush he can have a sight that works no matter. I love the concept.

Personally i run mine with a modern optic that has an intelligently designed reticle i can reach out with and many time i just use the irons as i really like them. Im going to put an 30mm Aimpoint with quick detach mounts as a backup in my fanny pack for this rifle and have a trifecta of sights for it.