AusVarmint

Hi all,
I am considering buying a howa /christensen arms varminter supreme in .243 as a dual purpose hunting long range varminting rifle, as it is light weight and rigid. I know uncle nick panned them in sporting shooter recently, but he did say he would like to have one after it had been pillar bedded. I have a howa .223 that shot 1- 1 1/2" moa when I bought it, (stainless synthetic stock) but since I pillar bedded it it shoots 1/2-3/4"
all day long (5 shots) with nos b/t, sierra bltz and v-max and I'm impressed with everything except the crappy synthetic stock.
I would appreciate it if anyone has one in .243 and has bedded it, if they could give me some feedback on accuracy and how heavy they are, and is the stock as good as uncle nick reckons?
Regards Alpal

I believe Troutman on AHN has one.

I've got one in stainless (not the carbon) varmint supreme (non-thumbhole) and its a damn fine piece, the only thing smoother that i've seen is the tikka/sako action.

its strong and smooth, its accurate and comfortable. What more could you want.

-Arch

Thanks easy, troutmans article was exactly what I was after, sounds like a great rifle.
Thanks again,
Regards alpal

Suggest you do a bit more research on the barrels . Haven't read a lot of good stuff about that manufacturer and the carbon wrap concept (like aluminium cricket bats) hasn't exactly set the World on fire. The accuracy nuts are still going heavy stainless .

hey there bushcook, i here ya, I know fat and round and stainless is the way to go if weight is not a prob, but I am looking for lightweight
and rigid. I thought I read somewhere that the septics were using similar barrels in benchrest to great effect and have been for some time.
Anyone else got any knowledge or experience whith the carbon barrels?
Troutmans article was pretty favourable.
Regards Alpal

Ive handled the said troutman rifle and was impressed with its light weight, good balance and nice stock. Unfortunately I didnt get to shoot it as the owner was running in the barrel on that particular session. I was that impressed with the feel and balance of the stock that I thought at the time you could almost shoot it one handed. I seem to remember that the stated (by owner) out of the box accuracy was quite acceptable also.
If I was going to buy another all purpose varmint / stalking rifle I would have to give one of these serious consideration.
Cheers Jethro

I seem to remember that Troutman also posted about a case problem that he was having, possibly looking like it would lead to head separation. This was (if I remember correctly) also involving this carbon barrelled rifle. I believe the discussion then went on to issues of headspacing and chamber stretching relating to the suggested inability to sufficiently tighten the barrel in the action because you can't grip the carbon tightly enough to apply enough torque. I may be wrong but you may want to do a few more searches on AHN. I also read a review in a mag that said the Howa/Christensen was not very accurate.

From experience of carbon fibre in other (non rifle) uses, it is very strong until it gets scratched, at which point it often fails unexpectedly at the scratch. I'm not sure how/whether this would apply to rifle barrels....

I believe the partial case head seperation problem was tracked down to overly long cases and a short throat in the howa christensen.
Cheers Jethro.

I like the look and feel of these rifles but am yet to shoot one. The case seperation issue was due to the brass not the rifle.
As with all things new it will take a while to catch on and the price will inhibit the use of these barrels.
A light weight that is as stiff as a heavy SS barrel must be a good thing for a hunting rifle and that is why I am interested.

Another thing to consider is the issue of thermal transfer. I know that Christensen say they are very good, but they would, wouldn't they? Carbon fibres transfer heat very well along their length, but in a WRAPPED barrel the heat needs to travel between layers to escape quickly. In a layered panel carbon fibre is often used as a heat shield, remember, although obviously the resin component plays a part in the thermal conductivity.

I was a little concerned that one review stated that the barrel felt cool to the touch. This would indicate that the carbon fibre is either acting as an insulator and keeping the heat inside or it is managing to radiate the heat to the atmosphere quickly.

Has anyone actually stuck a thermometer up the end of one of these barrels after firing a clip?

I would assume if it's not absorbing the heat it's simply going out the end of the barrel where it should go. Unlike steel with has a nasty habit of soaking up the heat. Got no idea really just ASS U ME ing.........

The heat generated by firing will be the same for any barrel. That energy has to be dissipated to the atmosphere somehow. Given that the energy is initially absorbed by the material closest to the bore (which is steel, even in the carbon sheathed barrel), it then has to pass through the remainder of the barrel before dissipating to the atmosphere.

If the barrel material is a good conductor of heat, the heat will reach the outside quickly and until the energy is radiated away it will feel hot. If the barrel material is an insulator, the heat will be trapped in the steel core until it can pass along the length of the barrel and radiate off the muzzle or action - some will escape via the bore itself but given no airflow along the bore I doubt it would be very much.

So, if the carbon barrel is cool to the touch it means that either it is insulating the steel core (which would therefore get/stay much hotter that the steel in a fully steel barrel), or it is much better at radiating the heat to the atmosphere than steel.

Heat radiation is dependant on various things including colour, surface area, and thermal conductivity. Carbon fibre is black, which is good, but so is (within reason) a blued steel barrel. Surface area will be much the same, assuming equal diameter barrels and that the carbon barrel is finished smooth not rough (ie you can't feel and weave).

Looking on the web, carbon fibres thermal conductivity is, er, interesting. Many pages report it's thermal conductivity as high, but these seem to deal mostly with the fibres themselves. Sites dealing with carbon fibre composite materials often state their products to have low thermal conductivity which is why they are used as heat shields and so forth.

I'm intrigued. Somebody get hold of one and stick a thermometer down the barrel to see how hot it gets!