I'm undertaking a project, that involves rebarreling and old Ruger KM77 in 300WinMag to 458WinMag, and I'm considering using Pacnor barrels.

Does anyone have feedback on the quality and company service?

Also, any comments regarding my project is welcomed!

Sounds like a godo project, and there will be very few complaints on pacnor barrels.

you may hear that cut rifles are better... and they better be, at 2.5X the price...

i understand one wellknown double rifle maker uses them exclusively

jeffe

quote:

Originally posted by jeffeosso:
Sounds like a godo project, and there will be very few complaints on pacnor barrels.

you may hear that cut rifles are better... and they better be, at 2.5X the price...

i understand one wellknown double rifle maker uses them exclusively

jeffe

Do you think that the original contour of the 300WM could be used as a template for the new barrel? Of course, that would be a "thin" 458WM, but it will the stock as a drop in. Any comments?

tks!

I might use another of their barrels but I'd never let them do the Smithing. I know countless others have had a different experience but more than a few share mine.

I would pick a heavier contour for a 458, barrel weight is a good thing in big bores I would want a muzzle dia of around .800" for the 458. It is well worth wittling out the stock to fit the larger dia barrel.

I haven't personally used pac nor, but have only heard good things about their barrels.

I don't own a PacNor barrel my self, but many of my friends do and they all like them very much.

Regards,
Kory

I have 4 of them and they are all very accurate and clean up quickly. Some take a bit more break-in to go to sleep, but that is the way with any manufacturer.

I have one I bought to play with the 223WSSM, and it's a good barrel. We had some hiccups during the ordering period (Savage changes shank sizes on us mid-stream), but all changes were made gleefully and without fuss.

She shoots half moa, which is about all I can do in a sporter configuration, anyway. Cleans up easier than my Shilens. HTH, Dutch.

I just put a PAC-NOR on my Model 70 and chambered it for .404 Jeffrey. The barrel came beautifully finished on the outside and nothing amiss that I could see on the inside. So far, I have been able to get MOA groups with 400gr. Swift A-Frames but, the 350gr. Woodleighs won't do better than two inches, usually three in under an inch with two about an inch away. Very satisfied so far.

One more question :

Which barrel will you order, since PacNor list three options : (indicating twist rate)

458 Rifle (.458")
3 groove 14"
6 groove 8" 16" 22"
8 groove 14" 15" 18" 20" 22"

Also, does anyone if it's possible to make an exact copy of the standard 300WinMag contour that comes with the Ruger KM77 ? That's in order to not change the stock.

If it doesn't match one of the existing stock contours then it comes under the heading of "special" contouurs and you pay a little more. Some people have trouble with Chris but that's because they speak "gunsmith". For example when a gunsmith says it should be ready in 2 weeks he is really hoping for 4 weeks but realizes it will probably be 6 weeks.

Gus,

Your 300WM barrel is probably close to a #3 contour. You can easily get a .375 barrel to that contour and could talk someone into making a .416 barrel to that contour if it is finished no longer than 22". I doubt you will get anyone to make a .458 barrel that thin. I was able to get a barrel maker to turn me a .458 to a #4 contour though. Keep in mind that a .458 at #4 cut to 22" would knock a good deal of weight off your 300WM barrel. Will make for a very light rifle but you pay for that in recoil.

Gary

I have gotten excellent accuracy from Pac Nor barrels.

I would go with the 3 groove,..but that will be personal opinion. I like heavy twists and less lands. I have a 6.5mm 1:8 4groove pacnor select match that runs a 140gr a-max into tiny holes as does it's sister in 5 groove. These 3-5 groove tubes are for real. And tighter twists allow a wider range of bullet selection.

Only barrel I use these days. I would not frown on some of the others but Pac-Nor is as good as any. I've got over 50 of them in the shop right now.

Besides, Chris and Penny are great folks to deal with.

You won't regret getting a Pac-Nor.

John

quote:

Originally posted by JustC:
I would go with the 3 groove,..but that will be personal opinion. I like heavy twists and less lands. I have a 6.5mm 1:8 4groove pacnor select match that runs a 140gr a-max into tiny holes as does it's sister in 5 groove. These 3-5 groove tubes are for real. And tighter twists allow a wider range of bullet selection.

Please could you explain the differences between the number of grooves and the twist? On the other hand, what are the specs of a standar Ruger barrel, for example in the Nro.1-H ?

tks!

There is a big debate going on, whether smaller numbers of lands/grooves offer advantages. The proponents claim longer barrel life (more land area to erode away) and less fouling (less land/groove borders). Opponents claim it does not matter greatly, whether you use a barrel with 3,4,5 or 6 (say) grooves. I guess it is one of those things in shooting, you won't get a definitive answer on that question.

About twist rates, I'm not sure what you already know?? So I'm a bit loath at offering a reply, lest I make a fool of myself stating the obvious. But this webpage: Shilen on Twist Rates Courtesy of Benchrest.com is a good place to start understanding the connection between twist rate, bullet weight (length really) and caliber. It won't tell you the whole story, but it provides easy answers, which will do 95% of the time.
- mike

I don't know what to say about the number of grooves definitively being better one way or the other from a scientific standpoint. I can say that my PacNor match tubes are 4 and 5 groove. The 4 groove seems to be a very tight barrel which stabilizes the 140gr a-max even at 100yds and the 5 groove are accurate as well.

I am currently a subscriber to the less groove= more barrel life theory as many long range shooters are getting stupendous round counts out of 4 groove and 3 groove tubes. Also, the lesser grooves, the less jacket intrusion, and the less number of lands and grooves to be held in concentricity over the length of the bore.

A standard factory rifle right now comes with 6 grooves of a noticeable smaller size than 3 or 4 bigger ones. The larger land width makes it more resistant to erosion, and the lesser number means the probability of one eroding at a different rate and making for destabilized rounds is reduced. That is my theory anyway,..but I have had great luck with 5 groove and 4 groove barrels and I tend to run hotter calibers, so any increase in throat life pays for the barrel.

Call and talk to Chris about it,...my gunsmith is very fond of him and his products as well.

A search on twist rates as well as following the link provided can help to lend some info on twists VS bullet weights. I am a longrange shooter at heart,..so my pills are always high BC Loooong bearing surface pills,..these will always fly better when stabilized by a heavy twist rate as their length will dictate. Also,..do a search on the "greenhill formula" for twists. It was eveloped for 1lb projectiles from artillery, but with a few minor modifications for small arms projectiles, it can be extremely accurate in determining the correct twist for the bullet you wish to use.

Thanks for the good answer!

In short, taking into account that I'm building a 458WinMag, that won't see many action as is common in other calibers, which groove/twist should I order ? What is the most common factory spec?

tks!

rem, win, ruger, and savage all use the 1:14 twist in the charts I have. I would have to choose the 3 groove since it comes in the 14 twist. I would like to see a 12 twist instead of the next offered 8 twist or 16 twist in the 6 groove. But maybe the 8 twist offers some advantage that a call to PacNor might make pertinent. I don't see you eroding the throat in a 458win any time soon,..so the erosion argument becomes a mute point. I would choose a twist that allowed heavy bullets for purposes like Africa should you ever take it there or hunt Kodiaks.

Many bullet makers will also give you their recommendation for twist rates for their bullets as well.

I have one pac-nor, its on a 404 jeffery, its very accurate, I am very pleased. They are really nice people to talk to when you order a barrel. I'd buy another, but I also like shilen barrels too.