The Accurate Reloading Forums
Building a 577 T-Rex

This topic can be found at:
https://forums.accuratereloading.com/eve/forums/a/tpc/f/4711043/m/72610727

18 December 2001, 12:03
RemUltraMag
Building a 577 T-Rex
I'm deciding on building a 577 T-Rex. How much would it cost to build it? Who should I get to build it? What action and stock should I use? Can I build it from an existing action? How easy is it to reload and where can I purchase factory brass and/or ammo for it, also how much does would these run me? I know I'm asking a lot but I know you guys have all the answers I need.
18 December 2001, 13:14
Paul H
First I thought you were asking about the Nyati, but T-rex, you are looking at one source of brass, Hornbear, and he's in Germany. As I recall, cases are $8 ea, and no one makes loaded ammo that I know of, though if it were available, I'd expect it to run ~$20 ea.

Not many actions are large enough for the round. Are you looking for a single shot, or repeater? The magazene/feeding work will be the biggest exspense. As far as suitable actions, the three off the top of my head are the CZ 550 416 Rigby, for ~$500, the Dakota which runs $1000 or more, and the Ruger M77 magnum, which are available as complete rifles only.

I'd figure a rough guide as $500 for the barrel and fitting, $500 for magazene work, $500 for a laminated stock, and $200 for irons, so figure $2-3k.

I believe Pac-nor has a chambering reamer, so could either build the rifle, or provide a pre-chambered barrel for the gunsmith of your choice.

Because of the brass issue, you might want to consider a 585 Nyati with the 3" case. It can dish out nearly the abuse of the T-rex, and brass is more available, and only $5 a case.

If you are looking more affordable monster guns, the 458 lott is a good starting place, and the 50 caliber on the 460 Weatherby (by many names) is about the most bang for the $.

18 December 2001, 15:22
RemUltraMag
Paul,

Thanks for the reply. So, I should build a 585 because of the brass situation or is it easier to make the brass? Does anyone make brass for the 585? I will be build a repeater. Of the 3 actions you suggestion, which is the best or strongest?

18 December 2001, 15:36
Mike375
RemUltraMag,

A 585 Nyati can be done on a Mauser 98 and that was the idea behind the caliber.

Basically, it is a 577 Nitro case, shortened back to 2.8" from 3", made into rimless and blownout with very little body taper.

This allows it to have a shoulder.

Bertam sells brass that is ready to size and trim back.

It is a bit smaller in case capacity than the 577 T Rex, but it will be more than ample

Mike



18 December 2001, 15:43
RIP
RemUltraMag,
Mitch Carter found that the BRNO/CZ action is too small in bolt/bolt face diameter to work.
The BBK action is a little bigger in bolt diameter and will work. You really ought to talk to Mitch about it.
If he doesn't post on this, you should give him an email. He knows the ins and outs of the 577 Tyrannosaur.

------------------
So many bovids! So little time and money!
RAB

18 December 2001, 15:51
Mike375
RAB,

I hope this thread runs for a while as I am going up the range soon with a couple of 375s.

Just reading these threads is enough to reduce the 375 recoil down to the rimfire level, actually a magnum rimfire

Mike

18 December 2001, 16:04
RemUltraMag
Thanks guys! As usual, you make new guys like feel right at home.
18 December 2001, 16:07
RemUltraMag
Mitch Carter,

DaggaRon suggested I get in touch with you regarding the 577 T-Rex. Could you give me details on your rifle and loads, I'm planning on building one?

18 December 2001, 16:15
Mike375
RemUltraMag,

Mitch has not been on the site much of late.

If you go to the top left of the page when you first open Big Bore forums you will see Mitch's name as moderator.

Just click on his name and then you are ready to email I him.

Mike



18 December 2001, 16:29
RemUltraMag
Mike375

Thanks much!

19 December 2001, 02:24
<Mitch>
Rem. Ultra Mag. My t.rex. is built on a BBK-02 action it has a larger bolt face than the Brno 602, CZ550 or the Big Ruger. Hornber is a good source for brass he gets about 4.00 each for brass. There is another company in Germany that makes it but he charges 8.00 each for his brass. I had Pac-Nor do my barrel and McGowen rifle barrels did the gunsmithing on my rifle, I had MPI make a fiberglass stock for it. No one that I know of loads ammo for t.rex, you can buy dies directly from RCBS or Huntintons. You can get one built for about 2500.00 to 3000.00. if you want a fancy stock it will cost you more.



19 December 2001, 03:29
rick3foxes
RemUltraMag,

You might be able to buy a complete T-Rex from Saeed, but I think it's been dropped two or three times...

19 December 2001, 06:24
500grains
For anyone building a 577 T Rex or 585 Nyati, I would suggest going with an action that has a bolt body diameter of GREATER THAN .700. 0.750" is about right. Otherwise, there is just a very thin sliver of metal left on the boltface to hold the case rim opposite the extractor.
20 December 2001, 17:03
Wildcatter
RemUltraMag,

500Grains is right about bolt body diameter. Just looking at the case dimensions, .708 of the BBK-01 bolt offered by Olympic Arms seems to me marginal for the Nyati and too small for the T-Rex. I know of noone making actions of larger bolt body diameters, other than 50 BMG actions and Fred Wells high dollar stuff, that come close to .750. Someone tell me when they find one.

Mitch,

How is the quality of your four-dollar-apeice T-Rex brass? Who is the maker and does he do 505 Gibbs? Custom headstamps? Everyone is talking about BeLL and a few others making 505 but I think plans are on hold for all of them for some reason.

-Catter

------------------
Shoot the largest caliber you can shoot well, and and practice , practice, practice.

20 December 2001, 22:23
<Mitch>
Catter, The quality is very good, I have 5 loadings on some of this brass and the primer pockets are still very tight. The brass is not as thick as A-Square brass and holds about 12 grains more water. If you want Horneber will make your brass with a custom headstamp. Horneber makes 505 Gibbs, 585 Nyati he even makes 700 Nitro brass.

[This message has been edited by Mitch (edited 12-20-2001).]

21 December 2001, 03:25
500grains
Wildcatter,

Granite Mountain Arms in Prescott, AZ offers a double square bridge magnum mauser action with a .750 bolt diameter for about $3500. You can get one all set up for either the 577 TRex or the 577 Nyati, as you please.

21 December 2001, 10:02
<OttoDude>
Mitch,
Could you post contact information for the Hornber company? I've done a few searches, but have found nothing...

Regards,

Otto P.

21 December 2001, 16:17
<Mitch>
Otto, Hornebers e.mail address is dhorneber@aol.com I misplaced his phone number, if I find it I will post it.
31 December 2001, 12:39
<Mitch>
Otto. Hornebers # is 49-911-753-0607 call him about 9 AM German time (6 hrs. ahead of EST in the USA).
31 December 2001, 13:43
<OttoDude>
Thanks Mitch, much obliged!

Otto P.

31 December 2001, 17:01
Rusty Gunn
Oh, my gosh! What exactly is one supposed to shoot with such a monster, other then making silly videos?
RUM... have you even shot such a rifle? I wonder about such cartridges, and why even bother? Esp after serious money has been spent on one! Fill me in on the 'whys' and 'why nots', please. ~~~Suluuq
01 January 2002, 06:45
<Bill Tompkins>
RemUltraMag,

I just got an e-mail from Ross at Prairie Gunworks about updates on his website. They now list 0.750 dia. bolt and receiver. Ross and Stephen are terrific people, you might give them a look.
www.prairiegunworks.com

Bill

01 January 2002, 10:05
Oldsarge
Rusty,
Except for the .500 Jeffrey, I believe that Class IV rifles are built for the same reason that people climb mountains, because they can. I'm unconvinced that just because something is possible that it is a good idea but you know about the difference between the men and boys being the price of their toys.

Sarge

02 January 2002, 10:46
RemUltraMag
For anyone asking questions as to what and whether or not we should hunt with large caliber rifles, thats no ones business but our own. This forum is for Big Bores rifles and anything topics relating to them. I dont question or even judge someone if they wanted to use their 700 NE on groundhogs. To each his own.

Oldsarge,

I plan on building the 577 for enjoyment of firearms of large caliber. I personally hunt with a 30-06, 300 Win Mag or my 338 Ultra Mag. And Ive taken animals ranging from Antelope to Elk. I love these 3 cartridges for that purpose. I am planning hunts, in the near future, to Africa. I will use my 375 or 416 when I go. Im not bashing you or your opinion, I just like BIG BORES, like everyone else in this forum.