All this talk about the 600 OK lately (and others) has me stirred up. I am ready to build a big bore.

I've got tons of 460 Wby brass, a CZ rifle and the cash to start a new project.

Sooooo, I'm thinking about the 550 Magnum. Why? I don't know, why would we build any of these behemoths? I just like the looks of the cartridge and it's plenty powerful enough.

Initially I had planned to have a 500A^2 built but now I am thinking bigger.

What do the judges think?

Landrum

I am prejudiced, but last year I designed and built a wildcat 550 caliber rifle using the 505 Gibbs as a parent case. It more than matches 577 NE 3" power levels, and will fit in an enfield or the spiffy new PH action from MRC. Thursday morning it and I will board a flight to Harare, Zimbabwe to test it on Cape Buffalo. Hold off until the 24th of this month and get a post mortem.

Rich
DRSS
Knowledge not shared is knowledge lost...
Did I mention FOUR DAYS!!!

Awesome! Good luck and safe travels.

I will be looking forward to your trip report.

Landrum

Yes, please do that!
Keep the .550 alive!

Neal did the 550 magnum, he did the 550 express, with me building the first one, then I did the 550 flanged, and then RIch did the 550 gibbs ...

ANY of them will deliver more recoil than you WANT ...

if you have a CZ 416 rigby action, send to pacnor, and have it done.

You MUST have a barrel recoil lug.

I just took delivery of a 550 magnum from Mike Scherz a couple of days ago (I believe RNS will be surprised by that). It was quite a wait but the gun did turn out fantastic, nice wood. I shot it this morning using some 600 grn bullets I bought from Neal a couple of years ago, I have some work to do to sort that out. The gun is a handful but very manageable. Shayne

I shot nine rounds of my 550 Gibbs this afternoon in about forty minutes, and all nine made a 6" group, offhand, at 50 yards. The loads were about a hundred fps lower than the brainbusters I had in Houston in February. 2385-2403fps. 140gr of WW748 and the 615gr Macifej solids (man I like what they do for penetration) good for about 7300ftlbs ME.

Four more days!!

Rich
DRSS
Knowledge not shared is knowledge lost...

Best of luck on your hunt. I can't wait to hear how both the cartridge and the bullet do on buff. It seems like an awesome combo. I'm tempted to try a 550 Express on an M77, but have WAY too many irons in the fire for the next few years. I'm jealous, but your report on the 24th will be an excellent Xmas present indeed!

Stay safe, shoot straight, post lots of pictures, and don't drink the water!!!!!!

Bob

Rich, glad you are going to "Blood" your 550. Also glad to hear that you are dropping a 100 fps off of that load you brought down here! Brainbuster is the right thing to call that load.

Jeffe is right, any of the 550s will give you more recoil than you want a steady diet of. Just load them to where you can get off aimed follow up shots, and not get rattled by the recoil.

Jeffe and I (as far as we know) are the only two to have shot all 5 versions of the 550s. 550 Mag, 550 Exp, 550 Gibbs, 550 Flanged, and 550 BPE.

Keith

quote:

Originally posted by shayneC:
I just took delivery of a 550 magnum from Mike Scherz a couple of days ago (I believe RNS will be surprised by that). It was quite a wait but the gun did turn out fantastic, nice wood. I shot it this morning using some 600 grn bullets I bought from Neal a couple of years ago, I have some work to do to sort that out. The gun is a handful but very manageable. Shayne

Wow -- Did you hear me fall on the floor?
i am calling Neal right now!

I'm glad you are letting Neal know. I tried to get ahold of him as soon as the gun showed up to try and glean some reloading advice from him. I was using WW748 and had a couple of hang-fires today. Shayne

I got his voice mail -- but I sent you his email address

So, what are some of the pitfalls (if any) building a 550 Magnum?

Landrum

quote:

Originally posted by shayneC:
I just took delivery of a 550 magnum from Mike Scherz a couple of days ago (I believe RNS will be surprised by that). It was quite a wait but the gun did turn out fantastic, nice wood. I shot it this morning using some 600 grn bullets I bought from Neal a couple of years ago, I have some work to do to sort that out. The gun is a handful but very manageable. Shayne

shayneC,

I am very glad to hear of your succesful 550 Mag rifle project from Mike. Some of us here have had less than pleasant dealings with Mike, and I include myself. I really hope Mike has got his act together because his business practices left a LOT to be desired.

I wrote off my losses with Mike as a lesson learned. I really like the 550 Mag round and hope you will enjoy it.

John

quote:

Originally posted by Landrum:
So, what are some of the pitfalls (if any) building a 550 Magnum?

Landrum

Shooting it!

Other than that, none. It's a natural in the CZ action while Rich's 550 Gibbs is a natural for the MRC PH. I think 2350 fps is about the practical limit for the 700 gr bullets in the Magnum but the Gibbs version ought to reach 2600 safely IF you buy thick-webbed Jamison brass. The older brands of 505 Gibbs brass are little light in thickness for that much load.

The best thing about 700 gr bullets at 2600 fps without a muzzle brake is you only need one in a lifetime.

Basically the 550 mag is the most doable with a .460 Wby case. With decent bullet availability its a great round. Easy to build on the CZ and proven. I've shot Neals gun and it was very controllable and pleasant to shoot. Accurate Too. Straight walled cases last forever and have minimal feeding issues. Go for it!-Rob

JKS
Mike has actually built about 12 differant rifles for me and have enjoyed the builing the experience. Most of the guns have been very satisfying to own and shoot.
The 550 had become a pia and I had written off the project,but Mike contacted me about a year ago after settling in Idaho, and we worked out finishing up the gun. As for the gun, I was partners in it with a hunting friend who goes to Africa almost every year, when he had it in his hand he said "After 4 years this was worth the wait". Shayne

shayneC,

Let us know how it shoots! AND keep us informed of it's hunting adventures. We need 550 Mag field reports. Always glad to hear of a good custom rifle project. Post pics of your rifle please!

John

I tested 550 Mag with long barrel and full
compressed loads of ball powder and got 600
grain over 2600 fps.Ed

Well - pacnor is going to be your best bet for a button rifled .550 ...

Bauska barrels, which is now closed and gone, could not locate my .550 tooling, and I can not send what I don't have to McGowen.

Now, before anyone gets too upset, they did offer to compensate me for the tooling, an offer I passed on and just told them thank you, but no.

If a couple of you guys would like, I can arrange to buy the tooling, again, for McGowen, or sweet talk those guys into trying a run of barrels.

Anyway, sorry about that guys, I really thought I would have that tooling at McGowen.
j

quote:

Originally posted by hubel458:
I tested 550 Mag with long barrel and full
compressed loads of ball powder and got 600
grain over 2600 fps.Ed

That's pretty impressive, Ed. Was it in the W748 range or faster like 30 Carbine pwoder?

Hubel458
I shot those 600grn bullets over 110 grn of ww748 and had a couple of hang-fires. So today I ordered a Corbin hand cannellure tool to put a crinmp on those bullets and then try again with 120 grn ooof ww748.
My buddy Pat Cooly is busy showing that gun to everybody in town, by next week I will get some pictures up. Shayne

Got to use Federal 215Mag primers, crimped hard.
and I used 130gr of H335. Enfield action.Ed

I have found h335 to be the best powder for the 550 express, and all the AR rounds. Neal got great results with it in the mag.

748 is too slow for max performance

That 550 Action is what I have in my Lott by CZ
That rifle could kill any animal in the world.
It shoots tight groups too.

Just want to add that I Love my 600 Overkill!,but the 550 sounds like a Winner too!

I will get you the loading data. I can wait to see the finished gun.

Thanks for the info; that is probably the one powder I never bought. I'm pretty happy with Rel 15 and the 700 gr bullets.