Want to find out what contours you have gone with when making your custom barrel.I have read some posts on this board and the 1:10 barrel twist in the .458 is a winner.How about the OD
muzzle diameter on the barrel .750 or bigger.
Would appreciate your input on contours for the .450 rigby class.

Thanks,
Gary

Gary,
On a 458AR ... I've just ordered a Shilen #6 contour, so 0.75" at the muzzle, straight taper. S&F will be getting a Shilen #5.5 contour for his 458AR, same muzzle diameter but contoured to be a bit lighter. Reason I went with the #6 is I wanted a bit more weight out front and over the front hand to steady it during off-hand shots ... so I'm searching for a "feel", plus building for a total weight of rifle just above 10lb on a Ruger action.

I'd suggest ... get your weight of action, stock and acessories ... determine the total weight of rifle your happy with ... then pick a contour.
Cheers...
Con
PS: Welcome aboard!

No No No! You got it all wrong!.... 450 Dakota is the way to go.... As a matter of fact, if recall there's a set of dies in the classifieds

MopaneMike,
Easy big fella ... just telling him what contour we're using on our 45cals . I think Weatherby run around 0.825" at the muzzle with the 460Wby which I reckon is a bit truck axle-ish.
Cheers...
Con

Mikey,

STOP THAT!!!

Rich
DRSS
Knowledge not shared is knowledge lost...

Con,
A #6 Shilen contour @.750 0D1 would be 6 lbs that's going to weigh in at 12.5-13 lbs for the rifle.Am I correct on the weight guess.I think my rifle will come in at 11.0-11.5 lbs. Do you think thats OK? My action tips in at 4.0 lbs roughly.
The #6 is a stout one by the way.Looks good.

Thanks,
Gary

FAST996,
It's 6lb with a 308" bore and full length blank. The larger bore will remove some weight plus mine will lose 4" of barrel blank to come back to 22". Extra meat near the chamber will hopefully move most of that weight between the hands which I prefer. Could also flute to take some more weight off if needed but I wont be doing it. I've had my time with sub-10lb big bores ... I figure the extra weight will make it a nicer plinker plus the weight is appreciated when shooting.
Cheers...
Con

Fast996,

you a Ter Blanche fan or one of the guys who wants to shoot his dog?

I am building a 550 Gibbs on an Enfield action. With a 13oz Breako recoil reducer in the butt stock, but no sights it weighs 10.5lbs bare. My barrel measures 26" long, is 1.285 at the breech and for 1.8" long, then is a straight taper out to .884" at the muzzle. It is a .550 caliber hole, so not as fat as it looks. Call it the Idaho DGR taper. If you go to the 550 pictures thread on the Big Bore forum you can see what it looks like. I am also building a .577BME, and will increase the dimensions to about .930" at the muzzle for it.
This rifle balances just at the front screw in the magazine box.

Rich
DRSS
Knowledge not shared is knowledge lost...

goto www.pac-nor.com
and use the barrel weight tool...
most companies post their barrel weight as a .308

to me, i generally like the smallest profile the company will make in a caliber, and no more than 1 size larger... unless it's a bench gun or a small bore.

1:10 or 1:14 ... you are building a 450 rigby to be lower pressure and since tanstaafl, anything the twist does has to ahve a price.

cz and winchester and ruger use 14 twist in their bigbore 45s ...

I'm having a #6 Pac-Nor Sporter on my 450 Dakota if that's any help. jorge

Hello Jeffeosso,
Can elaborate on your comment:

"1:10 or 1:14 ... you are building a 450 rigby to be lower pressure and since tanstaafl, anything the twist does has to have a price".

Thanks,
Gary

certainly
**IF*** twist is used that is faster than REQUIRED, there is the tendency for persons to state that it increases penetration ... should one accept that, then, as with everything else, there is a cost.

In matters of twist, increasing twist WITH THE SAME LOAD increases pressure.

since There Aint No Such Thing As A Free Lunch (tanstaafl), any increase in performance has to have a balance in the equation.

So, if you are faced with a 1:14 twist or a 1:10 twist barrel, and you use FACTORY ammo, without question, the pressure in the faster twist barrel will be higher than the standard twist barrel.

Is that, or the additional penetration significant? Only scientific and peer-reviewed testing can possibly reveal.

Does pressure increase? without question. Does penetration increase? Might, but probably not 1 whit more than the increase in pressure.

What's the "real" difference?

Probably the difference in chose of a ford or a chevy, for all practical purposes.... after all, the 500 NE with a 28 twist has been killing animals dead dead dead for over 100 years

jeffe

In building my .458 AR on a Parker-Hale Mauser action, I used a 22" Douglas silhouette profile barrel. With a Fajen's synthetic stock, some lead in the forend, and a chunk of aluminum acting as a recoil transfer block between the recoil lug and the stock, the rifle came out at almost exactly 10 pounds. I think that's about right for the .458 AR caliber.

The silhouette profile is a bit beefier than a Douglas #5.