Posted this on the Gunsmithing forum also--thought you big bore guys might have some thoughts as well.......

I recently purchased a rifle with a switch barrel system, and it has a 416 Rem Mag barrel. I have been able to locate several factory loads, and enough compnents that I am comfortable that I can get a load worked up for it.
My question is just for general FYI, is this a good 40 bore round, or is it something I should look at trying to rechamber the barrel to another 40 bore? I know the Rigby isn't belted, and I do like non-belted stuff, but I don't figure to shoot this particular round much, so I was thinking it would be OK as is.

Any info, thoughts appreciated.

Thanks--Don

It's a fine .40+ cartridge, good for any game on the planet, including elephant.

George

Thanks George, I've actually ordered some dies and supplies based on some other feedback from the gunsmithing forum. I guess like anything else I had a little post purchase buyers aprehension, but I am now quickly transitioning into anxious excitement!

Regards--Don

I know this is an amateur question, but why would you prefer either a belted or an unbelted
round. What are the advantages and disadvantages? Thanks, John

As they come from the factory, rifles chambered for belted cartridges headspace on the belt, while unbelted cases headspace on the shoulder.

In not-so-simple terms, headspace (if you are unfamiliar with the term) is the dimension of the chamber of your rifle, the gap between the face of the bolt and the stopping surface for the cartridge. To be precise, it is the distance between the face of the bolt and the datum line, which is a circle of stated diameter, along the slope of the shoulder of the cartridge.

On a rimless cartridge such as the .308, the stopping surface is the shoulder. On a rimmed cartridge like the .30-30 or .303 British, the headspace is the gap for the rim. On a belted magnum, headspace is the gap for the belt. Since not every rifle or cartridge can be made to exact dimensions, with perhaps the best custom rifles being one exception, headspace is deemed to be correct if it is within a certain range.

So (in simpler terms), when you chamber a rimless cartridge (let's say a .30-'06, since it's now 100 years old!), the case slides into the chamber and stops just where the shoulder of the cartridge meets the machined shoulder in the chamber. Should the headspace be too short, the cartridge will not chamber and the bolt will not close (or close VERY tightly!). If the headspace is excessive, the brass case may be unsupported and the case may rupture upon firing.

Belted cases slide into the chamber and are stopped when the belt at the rear of the case contacts the machined surface at the rear of the chamber that was created to match the belt on the case.

However, belted cases (after firing) can be resized to headspace on the shoulder. This is important in some rifles, as headspace borders on excessive to promote easy feeding, and after 2 or 3 firings (sometimes just the intial firing is enough), reloaded brass starts to crack due to excessive stretching. My Ruger M-77R .338 Win Mag had this problem before it was rebarreled. I had to neck-size only. Full-length resizing made to cases unusable after the first reloading.

I hope this explanation helps.

Actually, I guess my first reply really did not answer your question, as you were looking for advantages/disadvantages. A lot of shooters prefer non-belted cases, as it is normally easier to reload unbelted cases without worry of short case life due to excessive stretching of the brass.

As far as factory fodder is concerned, for the most part I feel it is much ado about nothing. Some rifles may be less accurate or lose some velocity if the headspace for a belted cartridge is sloppy, but if the chambers are cut correctly, normally you will have no problems with factory cartridges. The .375 H&H Magnum is a belted round; so is the .300 H&H Mag. The .300 H&H is probably one of the slickest-feeding cartridges in existence.

I say, if you like the cartridge, lack or non-lack of a belt should not sway your opinion too much.

Bdhuntr, thanks very much for the well thought out answer. That makes sense John

It's all relative. I have a Remington Model 700 BDL chambered in 7mm Rem Mag that my father bought new in 1965, which was shortly after its inception. It is one of the most accurate rifles I own, and it would be the most beautiful, if not for the impressed checkering (but my Lord, what a beautifully figured piece of walnut on a non-Custom Shop rifle).

I have handloaded both 150-grain Nosler BT's and 175-grain Partitions for it, and brass life is great, and I full-length resize the cases.

In the long run, I would prefer non-belted cases over belted (rifle for rifle, I think you will have less problems with non-belted cases), but the vast majority of belted magnums perform admirably.

I am wanting to get into reloading this spring. The two cartridges I want to reload are 6mm remington (non-belted) amd a 300 weatherby which is belted. I really do appreciate the heads up. My ex-father-in-law was great for suppling reloads for the 6mm, but as he is now an ex, plus with the 300 which costs a buck and half per bang, I am going to have to reload my own in order to shoot as much as I like. John

quote:

Originally posted by bdhuntr:
It's all relative. I have a Remington Model 700 BDL chambered in 7mm Rem Mag that my father bought new in 1965, which was shortly after its inception. It is one of the most accurate rifles I own, and it would be the most beautiful, if not for the impressed checkering (but my Lord, what a beautifully figured piece of walnut on a non-Custom Shop rifle).

I have handloaded both 150-grain Nosler BT's and 175-grain Partitions for it, and brass life is great, and I full-length resize the cases.

In the long run, I would prefer non-belted cases over belted (rifle for rifle, I think you will have less problems with non-belted cases), but the vast majority of belted magnums perform admirably.

Take that gun and have it checkered by someone who knows what they are doing. You can have the checkering done over the "impressed" checkering. I had that done to an old Ithaca Shotgun, and it made it look 100% better.

Actually, I just read an article in a gun magazine showing that exact thing! Personally I think it's a little beyond me, but a 'smith who does checkering could probably do it without a hitch.

It has a great piece of wood for a standard factory rifle, that's for sure.