Well after 3 long years my Ruger Safari Magnum 375 H&H to 500 Jeffrey is finally complete.

I was able to snap off a few quick pictures before I took it to the range last night. I am posting this information for those brave souls that are or will contemplate making the plunge. I was originally going towards a 505 Gibbs conversion like the old Hamilton Bowen jobs but was talked out of it by Jim Dubell who did the work. He felt the bolt would need to be opened up too much to be safe for a working DG rifle. I decided on converting the RSM because I liked the looks and it was available since I only paid $799 for the rifle in a local shop back in 2003. Jim put many more hours into the project than what he charged me for so I can tell you the total was less that a new CZ 500 Jeffery. The fact this rifle works it a testimate to his exceptional gunsmithing skills.



A couple of notes. He manufactured a new feed box, follower and floor plate so that the rifle could have 3 rounds in the mag (Bowen’s 505 only had 2).




The rifle does have a recoil reducer but the gun is still very light for a 500 Jeffery less than 10lbs. I wanted more weight in the gun but it wouldn’t balance right for Jim’s liking.


I opted for platinum wire on the express sights and it works great.


Overall I am very PLEASED with the result. I will say on the record that this rifle is at the top of my comfort level. After firing 10 rounds with it last night I can say the rifle may pick up a nick name of Mike Tyson jr. I can shoot 20+ rounds out of my 458 Lott and still be ready for more but this 500 is a different story. I now better understand about shot to shot recovery time when you shot the big stuff. I am probably going to find one pet load and just live with it. Last night I shot 570grn woodleighs and 570 Hornady solids the round nosed woodlieghs feed like greased lightning but the solids would hang up with the flat metplate when feed from the left side of the mag box. Also the Jamison brass I used was from an older run and it may need to go back since I found some issues with it that I’ll discuss in a different post.

My RSM Family finally Together (500 Jeffrey,458 Lott, 416 Rigby)


My advice is a 50 cal is well worth the investment and wait. I see the wisdom in something like a 495 A-Square or similar (ie straight case 50cal). I wouldn’t recommend getting a 50cal if you think a 416 Rigby is a real big kicker. Weight is your friend when it comes to big rifles. It is good to practice shooting your 416 or 458 in between shots with your 500 since it will build you confidence. I like this conversion a lot and would recommend it if you want a 500 Jeffery for less that the cost of a custom gun ie (Empire rifles…). However, if cost wasn’t an issue I might go with a new gun build from scratch with everything you want. Yes, this is a keeper now onto getting my load worked out. I will post some better pictures once I get a chance.

Thanks for Reading

Brad

very very nice!

Just curious...What are the two holes in the stock of the rifles between the magazine and end.? I have not looked at a RSM that closely, I assume it is normal since it shows up in all three of yours.

Nice looking rifle BTW.

quote:

Originally posted by akperrydog:
Just curious...What are the two holes in the stock of the rifles between the magazine and end.? I have not looked at a RSM that closely, I assume it is normal since it shows up in all three of yours.

The barrel lug is bolted to the forend of the stock for extra strength.

Is that a re-bored factory or new custom barrel? Is the jeweled bolt original? The rifle is a real gem! Another 500 caliber straight wall case besides the 500nitro,the 495 a-square you say,another gem!

Shootaway:

The rifle started out life as a 1st generation Ruger Safari Mag an early 780-XXXXX serial number gun 1st production year (375 H&H). I sent it to Jim Dubell (Delta Gun Shop) who also is part of clear water reboring in coville, WA. Jim did all the work. The gun came to me with a jeweled bolt. He blued the extractor which looks a lot nicer than when it was all jeweled. I feel the 500 Jeffery is fiting given the british styled rifle but I can see why someone would go for a larger straight walled 50cal cartridge rather than play around with a 500 Jeffery. Jim made it work great but as you can see it wasn't just a rebore and feed ramp adjustment.

Brad

Brad, a fast amd easu way to add weight to a big bore, is to get one of the black elastic ammo carriers and put it on the rifle butt with 8-9rounds of ammo. It is quick. simple and cheap. Plus you have anni for a quick reload at hand.

Keith

And Jim cannot spell "500 Jeffery" either?
Another one!
It's like an epidemic of "Misspelling Flu!"

I see no new washer recoil lug on the action.
I do see the Ruger integral quarter rib.

This is a rebore.

This rifle still has the original Ruger recoil plate contraption.
No recoil lug on the action.
There is a little round bolster on the action that fits into a hole in the plate that reaches up into the forearm,
where a single recoil lug is anchored in the forearm.
That is the only recoil lug on the rifle.
Standard Ruger RSM bedding.

This is not all bad.
It is a supremely accurate bedding system.
Not the best for stock survival however ... unless there are crossbolts fore and aft of the magazine box, and a third (hidden) crossbolt in the forearm to back up the recoil plate.

From the looks of it the first generation RSM .375 H&H had a muzzle diameter that was about .750"?

That would be a bare minimum for reboring to .510 caliber grooves.

No wonder it is so light.

I guess it is butt heavy with such a light barrel, if it has mercury in the butt and no weight in the forearm ... no ... it has a steel recoil plate in the forearm and may be perfectly balanced!

I am inspired to rebore Ol'Purple to 500 Mbogo.
That will hold 3 down with no modifications to the box required.
It is a second generation RSM .416 Rigby with muzzle diameter of .820" and weighs 10.75 lbs dry.
Ought to weigh right at 10 pounds or just over when the barrel is hollowed out.

However, I am torn between retaining the RSM single recoil lug in the forearm,
versus adding a washer lug between the action and barrel as a primary,
and an add-on recoil lug to the barrel as secondary,
and throw away the recoil plate contraption ...

Finally, about the cartridge selection of 500 JEFFERY instead of 500 Mbogo: My condolences.

500 Mbogo:
longer cartridge
fits RSM box without mods
lesser case head diameter
lesser bolt thrust
same case capacity
therefore more power potential
nonrebated rim and longer neck for surer function
and only a rebore and rechamber away from a standard RSM
except for that bedding system quandary
which is the same with any cartridge in an RSM.

really nice looking rifle!

To clarify the spelling. Jamison ran their original brass with the 500 Jeffrey head stamp. If you don't believe me I'll post a photo. Jim labeled the rifle accordingly. Now Jamison labels the brass correctly 500 Jeffery go figure? Jim did right based on what I sent him. Since I don't plan on going to africa in the near future its just fine for me. If it becomes a big issue I'll just have it changed before I go. Also there is a wrist pin in the pistol grip area and he put in some hidden staples around the mag box before he glass bed it. Ideally he wanted to fit a custom stock to the gun and start from stratch to do it right, however, my lack of disposable income forced him to make due with the factory stock. Oh well, if she breaks I guess I'll get the custom stock after all. I plan on firing many rounds in it before I'd take anywhere so we'll just have to see what happens.

Brad

Brad
really ... no one is going to read more than 500 j.....!!!!!

Have you shot it yet? I am curious to know what a 10lb 500 jeff is like.

i did a 10.5, a 10, and then a 9.25 .. its STOUT, but fun to shoot .. .535 at 2350 isn't all that much more than a good lott load .. and most CZ's are around that weight...

For Clarification

Brad

Brad,
I'm just glad you did not spell it "500 Jeffreys."

We know all about that headstamp booboo.

Two Wongs don't make a White, however.

It should never be "necessary" to misspell the barrel engraving, to match misspelled brass.

If you are worried about customs agents being able to read and noticing one was spelled correctly and the other was spelled incorrectly ... it ain't gonna be a problem!
The rifle is durable the brass is expendable.

Very nice trio of Rugers. I really like my lite weight 500 Jeffery. Love the power.

Beautiful. Congratulation for the rifle.

Oscar.

Very nice rifle you got there. Congrats

Thanks gang for all the support. I have to again say that for what ever reason laws of physics aside "I think that the 500 Jeffery kicks harder than the 458 Lott given the same Ft Lb load" This rifle has a mercury recoil reducer and a nice butt pad but still punches harder than my stock RSM in 458 lott load for load.

On a bright note Jamisin has agreed to swap me out old Jeffrey Brass for New Jeffery Brass so my gripes about the brass having issues will soon be solved hopefully. It's been three long years to get my first 50 cal and I'm happy to say it was well worth the effort. Not sure what I'll do with that MRC PH action when it shows up since I'm so happy with the ruger right now.

Brad

It seems like the Ruger RSM in 416 rigby is a great option with it's .810" muzzle to rebore to .510" and keep the sights and quarter rib.

Rip... The perfect 500 Mbogo conversion platform.

I would like to see a 500-416 Rigby for brass and barrel stamp issues.

Keep the original .5" neck of the 416 rigby so the shoulder is in the same location on the blown out cart for a tad shorter 500 Mbogo.

Just another flavor.

Yes Rip the 500 Mbogo is flawless

welcome to the .500 jef club now go get a cape buf with it

Brad
Those big Rugers do make a fine looking, and shooting rifle! I had one in 416 Rigby that I had SSK convert to 510 Wells a few years ago. Very nice rifles.

As for the spelling, I think I mentioned somewhere else that one needs not worry about that at all, most customs personnel can't read, much less spell correctly!

Great looking rifle!

Michael

Good show Brad

Project well worth doing. The .500 Jeffery is a glorious cartridge and you matched it with the finest large bore factory rifle available, the Ruger RSM.

fwiw, I like the 535gr cruising around 2400 fps.

Grover looks excited too!!!!!!

Congrats on a Nice Conversion to a Great Caliber ...It puts them down...I nailed two Cape Buff's in Tanzania in 07'....BOTH were One Shot Kills with Barnes 570 XLC Copper "Softs"...

Thanks gang for all the words of support on this project. Again I would highly recomend Jim Dubell for all his work on getting this together for me. I agree that the looks and cartridge go good together.

Brad

Very nice rifle. The big 50s are a real step-up from the 458s. I had an early Ruger 77 416 Rigby, a beautiful rifle with full length fiddleback "Circassian" walnut, had the heavy barrel. Excellent candidate for rebore, maybe even up to 550 for those inclined.