Has anyone built a .408 Chey-Tac or a .416/.505 Gibbs wildcat as a 9 to 10-pound package?
That has got to be an ultimate of some sort.

Here is the reamer print from JGS, with some of the mm measurements converted to inches for us metric challenged:



Interesting to note no taper in the chamber/reamer neck, neck-1 = neck-2.
And the chamber neck diameter minimum has the usual sporter spec. slop of .004" greater than cartridge neck diameter maximum.
And the chamber length minimum has the usual sporter spec. slop of 0.015" greater than cartridge brass length maximum.

But, the parallel-sided free-bore is only 0.085" long.
That is less than "one-quarter-caliber."

P-S free-bore diameter is .4085": That is only 0.0005" greater than bullet diameter.
Meant for accuracy, eh?

That's a pretty tight throat. Nice.

2mm, 0.085" of parallel freebore. T I G H T. Just about enough room for one seating band.

quote:

Originally posted by 416Tanzan:
That's a pretty tight throat. Nice.

2mm, 0.085" of parallel freebore. T I G H T. Just about enough room for one seating band.

Yes indeed, though a reamer could be made with another throat, especially if the caliber is necked up to .416-caliber.
.416/.408 Chey-Tac anyone?



That would be much prettier than the .416 Staghound aka .416 Snipe-Tac:

I'm watching from the sidelines on this one…

quote:

Originally posted by capoward:
I'm watching from the sidelines on this one…

I'm with you on this Capo.

Thinking about a 416 Chey-Tac makes me happy to think of my 416 Rigby walkabout . The 130 grain case capacity is just about perfect for a .416" rifle. The 307.5 grain CEB Raptor can be launched at 3000 fps, and the more traditional 350 TSX and TTSX bullets can be sent out at 2800-2825 fps. Those just cover all of my bases, out to a very rare 400 yards. I can't see a need for a 1000 yard buffalo gun.

Anyway, a 416 Rigby in the palm of one's hand just feels like all-around Africa . My son is coming around on this, though he still likes the 338 WM (7.5 lb scoped) for ultimate hunting comfort. The recoil of the full Rigby is on the upper end of "reassuring and comfortable," though I haven't practiced prone yet. 6000 ftlbs is probably pretty close to a limit for me on prone. I've rarely shot or practiced prone with lesser calibres, so I would need a careful build up.

OK guys, you talked me out of a .416-caliber wildcat of the .408 Cheyenne-Proprietary-Tactical wildcat, which is still not recognized by SAAMI nor CIP.
I will stick with the .408 Chey-Tac wildcat.
That is wild enough for this cat.
There's getting to be plenty of .408 bullets available lately,
and the .410 and .411-caliber offerings will be easy enough to size down to .408.

Rip I think either is a grand idea. Pure macho factor of course, a cartridge that can beat the pants of the current 416 offerings.

The 416 gibbs/CT has been done a few times I know of, sniptac/staghound as mentioned, the first 408 CT derivative wildcat was the 416 PGW by prairie gunworks in Canada who were affiliated with jensen and the developement of the 408CT in the day. Also an Aussie poster here 416sw did a 416/505gibbs a few years ago.

You need to log in at www.longrangeshooting.com to get the full effect these guys have basically paralelled our bigbore wildcatting for hitting things out to a mile. Be careful it its addictive, you may find yourself 'needing' a 416 again that can take elk at 1000 yards

Some of their 'regular' hunting bullets here...
http://www.rmbullets.com/page9.html
http://www.rmbullets.com/page8.html

Karl,

Site gone TU?

"Click here to buy LongRangeShooting.com for your website name!"

Oh, well, probably better that I never got involved there.
Those are some nice bullets for the .416 Barrett as well as the .408 Chey-Tac.
I definitely need some of those.



.416 RBTAT Match/Hunting
The .416 RBTAT is a premium match grade bullet specifically disigned
for long range .416 cartridges like the .416 Barret.
This advanced ULD projectile brings out the full potential of your long range
hunting rifle.

Weight 450gr.
G1 BC =.923 G7 BC = .445 SD = .384
Design Velocity - 2800fps - 3200fps
Suggested barrel twist rate for bullet stability greater than 2800 fps is 1:14

Sold in packages of 100 @ MSRP $225.00
Ships via USPS Priority Mail to lower 48 states included in price.



Comparable .408 bullets:




More bullets at CheyTac USA LLC: http://www.cheytac.com/

CHEYTAC .408/419 Grain Cartridge
 (Patented) Balanced Flight Technology
 High kinetic energy at extreme distances
 Combined speed, distance, and superior accuracy at extreme long ranges
 Copper Nickel Alloy projectile
Ballistic Coefficient: .949 (average over 3,500 yards)
Weight: 419 Grain
Length: 4.303
Velocity: 3,000 fps
Muzzle Energy: 8,372 ft. lbs.

And here is an 11.75 pound dry-weight rifle (sans scope and bipod) that is offerred there, single-shot:



I am thinking 8.75 pounds dry-weight and a repeater on a CZ 550 Magnum.
Then you weld 2.5 pounds of scope and rings to it and it will weigh a manageable 11.25 pounds.

In a CZ Kevlar stock with a stainless, fluted No.6 Dan Lilja sporter barrel, 26" long (if he will do one that light in .408-caliber):
Absolutely it is possible to make the weight under 9 pounds dry.
The same CZ rifle action and stock with a fluted stainless Lilja .375-caliber barrel of same contour and length weighs 8lbs.15oz., in .375/404 Jeffery Saeed of 2012 chambering.
The bigger-holed .408 barrel will make it lighter than that.

Use a scope and rings that weigh only about a pound and an ounce, and the "Sporting .408 Chey-Tac" will weigh less than 10 pounds, scoped,
and look exactly like this, externally:

The bolt face of the 8.75-pound Sporting .408 Chey-Tac:





This recycled photo shows how many the box will hold:

3-down in .505 Gibbs
5-down in 404 Jeffery


And finally, this recycled photo represents the fitting of a .408 Chey-Tac into a CZ 550 Magnum:
Though it may be a tight fit, it should be fun, and with proper precautions, not too dangerous.

Sporty!

quote:

Originally posted by RIP:

Though it may be a tight fit, it should be fun, and with proper precautions, not too dangerous.

Sorry Ron, try this one
http://www.longrangehunting.com/
Nice plan ! I still think you should also consider the ultimate sacrilege of a scaled up remington clone and detach mag. A trashier girl but you will get more shots away so to speak

http://www.cheytac.com/images/McMillian%20A5.jpg
http://www.cheytac.com/Products/CheyTac408.php
http://www.wyattsoutdoor.com/index.php/cPath/2

Australia is big on this sort of thing, being low on class as we are. http://www.pseco.com.au/Hunt_Var.htm

Karl,
Viva la difference, but I got enough of those fat, ugly girls already. Just looking for something a little sexier, more sporty than tactical.
A stealth .408 Chey-Tac that could pass for a more mundane .375/404 Jeffery on a CZ 550 magnum.
I am still in the parts collection phase.

Its a great idea Ron. Just the sort of fresh air we need here these days as it has nothing to do with

1. noncon bullets
2.recommendations to AHR
3.favorite loads in a 458lott.

Its even naughtier than posting a weatherby lazermark on the African forum

Jeff Cooper would have asked, "What is it for?" Ballistically, would appear to be a fine sniper round, but for real-world hunting...what is it for?

quote:

Originally posted by mauser93:
Jeff Cooper would have asked, "What is it for?" Ballistically, would appear to be a fine sniper round, but for real-world hunting...what is it for?

Use all the .410 and .411 caliber bullets sized down to .408 for anything from squirrel to blue whale.
Still have lots of VLD bullets for precision long range targets or hunting (see above).
Even have a Sierra MatchKing in hopes of resurrecting the MatchKing mirth making.

It is mainly about fun, and pushing the envelope.
And CEB makes bullets for it too.

JD will probably chime in when he sees this thread. He bought my 505/416 reamer a couple of years ago and is building or just finished a 416 Gibbs on an MRC PH action.

A little smaller bullet, my 338 Snipe tac rifle will get a 300 grain bullet out the barrel at 3550 ft/sec for 8396 ft/lbs. It is one flat shooting son of a bitch and will reach way out there!

quote:

Originally posted by tiggertate:
JD will probably chime in when he sees this thread. He bought my 505/416 reamer a couple of years ago and is building or just finished a 416 Gibbs on an MRC PH action.

Hope JD adds some experience here, or how about you, tiggertate?

Mingbogo's thread on the MRC PH action:

http://forums.accuratereloadin...4711043/m/3101074381

Of course the PH option will add some weight, and does not have a CZ Kevlar stock to go with it ...

But a stainless PH in a walnut stock
Reinforced out the wazoo
Would probably only add a pound or two.

Not quite a haiku ...

I am trying this on my phone.I have barrel installed anc chambered. It is 28"long and is
s 1".125 dia. I am almost ready to bed it into a reinforced a2 stock by mpi.I have some
dummy rounds made up. Pm me your # I can tx a photo.



JD

Can I vote 416?
Most soft bullets would be like varnmit grenades on impact. 300 Raptors could do some serious damage at 3,500 plus fps. Maybe petition to get the 416 ER raptor for that project. If you go 410 the 300 405 win bullets would be a hoot but I think at Mach III you want mono metal bullets. 400 Gibs-RIP does have a nice ring to it though. Give it that Lapua shoulder angle you love so much for belt feed full auto I think a mag fed with VLD shortened version is more interesting to me. A sort of Mini Chey-Tac sporter for the CZ.

quote:

Originally posted by RIP:

quote:

Originally posted by tiggertate:
JD will probably chime in when he sees this thread. He bought my 505/416 reamer a couple of years ago and is building or just finished a 416 Gibbs on an MRC PH action.

Hope JD adds some experience here, or how about you, tiggertate?

Mingbogo's thread on the MRC PH action:

http://forums.accuratereloadin...4711043/m/3101074381

Of course the PH option will add some weight, and does not have a CZ Kevlar stock to go with it ...

But a stainless PH in a walnut stock
Reinforced out the wazoo
Would probably only add a pound or two.

Not quite a haiku ...

I decided I had enough on my plate and never built a rifle before I sold the reamer to JD. I still have thge action; waiting for me to build another 505.

JD said I could post these.
I will let him do the narration.
Meanwhile I will study this and add 416/505 Gibbs back to the thread title.
I might be waffling from .408 to .416, again ...
I also ordered an MRC PH stainless Gibbs action yesterday.
Will took the order.
Will said they had some PH "Rigby" actions in stock, and were finishing up some PH "Gibbs" actions to be available to ship soon, within month I guess.
We shall see.

I ordered a priming head piece for my Sinclair priming tool made especially for the 408 Tac.I am hoping it will fit my 500NE case.

RIP

that looks like a great allaround hunting round.

Just be careful with the tight freebore.

quote:

Originally posted by 416Tanzan:
RIP

that looks like a great allaround hunting round.

Just be careful with the tight freebore.

Good point.
I will be getting my own reamer made and specify my own throat,
like was done on the 500 AR Nyati.
That will require a study of bullets to be used.

Mingbogo's .416 Rigby PH:



The 0.800" MRC PH bolt diameter is 0.100" greater than the bolt diameter of the CZ 550 Magnum, which barely fits a .505 Gibbs:



I tend to have a habit of building two of each caliber. A Light and a heavy. Parts are accumulating.

That is a 308 and a Hornady 450 gr with the 416/505
My driod does not work well with posting on this site.


JD

quote:

Originally posted by RIP:

quote:

Originally posted by 416Tanzan:
RIP

that looks like a great allaround hunting round.

Just be careful with the tight freebore.

Good point.
I will be getting my own reamer made and specify my own throat,
like was done on the 500 AR Nyati.
That will require a study of bullets to be used.

I believe it was posted in another thread awhile back that the MRC PH has a 3.900" magazine length. If this is correct then the 0.180" PS freebore my be just fine for those pointy nose high BC hunting bullets to properly feed from the magazine without excess length-space without excessively consuming powder space.

Jim,
Mingbogo said the box was +4.000" inside,
as I recall MRC was looking at making it that long, by design, not by accident.
See Mingbogo's thread.
Cheers to MRC:

The ph action handles the round as it comes but a little work will smooth things out.

I went 416 because because of the cheep Bullets avaible. The barnes tsx shot
1/2 moa out of my 416 rem.once fired 505 formed ok

I lost a few cases some annealing. may help.

I have tentative acceptance by Rusty McGee to build a .408 Chey-Tac.
I offered to sign a waiver of liability, and he chuckled over the phone, maybe rolled his eyes, not sure, probably both:






Montana PH action is on the way to Hilltop Gun Shop.

Maybe that will be a standard .408 Chey-Tac in whatever stock from MRC for PH is most suitable, not finalized.

Additionally, a flyweight CZ 550 Magnum "Kevlar" weighing about 9 pounds with 26" barrel is conceived.
Chambered for the .408 Chey-Tac with special throat, it could also be additionally barrel-stamped "400 Berry Gibbs" just for fun,
for use of resized 400 Whelen bullets from .411 to .408 caliber.
A true "400-Bore"

Rip, before you go too far read the post on LRH on why you should not build a 408 Ct on a Gibbs Mrc. I thought of it and went with a 375 sporting Sniptac because the bolt face is not strong enough to handle 65,000 psi. Do you self a favor for safety sake. unless you keep to 35,000 of course.

RIP, have you thought of using a larger action? I've been toying with using the Barnard P-CheyTac action:

http://www.barnard.co.nz/model-p-chey-action.htm

ATB, Peter

quote:

Originally posted by LR3:
Rip, before you go too far read the post on LRH on why you should not build a 408 Ct on a Gibbs Mrc. I thought of it and went with a 375 sporting Sniptac because the bolt face is not strong enough to handle 65,000 psi. Do you self a favor for safety sake. unless you keep to 35,000 of course.

LR3 not sure where the LRH guys are getting that from as I can't see PSI limits being any different between 408 and 375 as its the same case .

Maybe they are talking bolt thrust?.In that case the 408 and any gibbs wildcats are mere pipsqueaks compared to the 585/600 wildcats used here. Do you have a link to the post?

quote:

Originally posted by LR3:
Rip, before you go too far read the post on LRH on why you should not build a 408 Ct on a Gibbs Mrc.
I thought of it and went with a 375 sporting Sniptac because the bolt face is not strong enough to handle 65,000 psi. Do you self a favor for safety sake.
unless you keep to 35,000 of course.

LR3:

So you have a .375 Snipetac on an MRC PH action?
Outstanding if so.

As Karl points out, the .375 Snipetac would be an egg in the same basket if it is based on the .505 Gibbs case.
You will have to load down to 35,000 (as you recommend) for the .375 Snipetac if a .408 Chey-Tac must be so loaded.

I am not a-feared o' bolt thrust.
No need to try to find what you are talking about at LRH, if it is bolt thrust, but if you can provide a link, I will look at it.
What else could it be referring too?
Surely the same would apply to the .375 Snipetac as to the .408 Chey-Tac.

quote:

Originally posted by PD999:
RIP, have you thought of using a larger action? I've been toying with using the Barnard P-CheyTac action:

http://www.barnard.co.nz/model-p-chey-action.htm

ATB, Peter

PD999,

No thanks. I can use a .416 Barrett if I want big and tactical, crew-served, or on wheels.

The object is a 10-11 pound, scoped rifle with 26" barrel, no muzzle brake.

If I dare, the old obsolete 305-grain Jamison International bullet was capable of 3200 fps (even in a 26" barrel, more in a longer barrel) with a BC of .661.
Heavier bullets are slower and have higher BC, jahwohl,
and recoil with all will be much less than the monsters many around here perseverate on.

I can size down a .411/300-grain TSX to .408 and shoot it at +3000 fps for a low pressure varmint load.
Size down all those .410-caliber 400-grainers to .408 and shoot them, instead, slower than 3000 fps.
And then there are all those +400-grain target and hunting bullets with BC's approaching unity.

They will be flat shooting and wind resistant even at submaximal .408 Chey-Tac velocities.

Re: .375CT vs .408CT
This thread may be of interest to you:
375-408

http://www.longrangehunting.co...f19/375-408-a-96195/

Rip here is the link that comes from the extreme long range forum on Lrh. Sorry if you misunderstood me but my Snipetac is not built on a Mcs action but a Lawton. Bat is an alternative. Yes the issue is bolt thrust and lugs if loaded to 64k psi.

LRH, thanks, here is the take on it from quick glance.

Appears Kirby Allen, aka Fiftydriver on that thread, a skilled and popular wildcatter for the long range crowd is saying the montana needs to stay at 45K PSI on the gibbs sized case. That's an easy one to explain if so, he is just flat out wrong

I can't argue with him on barrel tenon and thickness and maximum pressures, you will need our equivalent level wildcatters here like Ed hubel to take him on in that.

But the fact is a lot of our cases are even bigger than the gibbs and far greater bolt thrust. If all the MRC, CZ550,GMA Brno602, M17, P14 actions we use were unsafe over 55K PSI probably 1000 members of the complete accurate reloading membership would be dead by now

Good post though, always good to hear others opinions.

Fear not:
Even the CZ 550 Magnum is approved for a steady diet of 55,100 psi (3800 bar) with a Gibbs case head in a 1.200" diameter barrel knoxform.
At that pressure, the sporting .408 CheyTac can propel 305-grain bullets at over 3125 fps from a 26" barrel.
It is about time we had some of these!
The 63,817 psi (4300 bar) max load for the .408 CheyTac will not even equal a proof load for the 10-pound sporter.
And recoil is pidly compared to what many "okes on the ground" put up with.
The .408 CheyTac could also be thought of as the "400 Underkill" when compared to the "600 Overkill."
Of course this refers to effect on the shooter, not on the game.