calibre choice

[batleyhunter]

Hi guys need some advise on choosing a calibre and set up for shooting different dissaplines like mcqueens, fclass or open fclass, benchrest, long range vermin plus deer stalking so dont want it too heavy to carry. My max distance i want to shoot is up to 600yards as i feel that this distance is far enought for me atm but would try 800 yards in time.

 

 

Regards James.

[Finman]

Hi guys need some advise on choosing a calibre and set up for shooting different dissaplines like mcqueens, fclass or open fclass, benchrest, long range vermin plus deer stalking so dont want it too heavy to carry.

 

Regards James.

 

Don't we all mate....!

[20series]

something 6.5ish!!!

 

.260 or 6.5x47

[tony]

something 6.5ish!!!

 

.260 or 6.5x47

 

YEP, spot on.

[terryh]

James,

 

That is a tall order for one rifle! (as you sat 'it' in your OP)

 

Potential to be 'Multi- purpose multi-useless'

 

Terry

[tackb]

Open f class and benchrest plus stalking so you don't want it too heavy ? I'm afraid your asking the impossible !

 

If you need it for shooting living things then that is what you must prioritise , you owe it the game animal, then you will just have to accept that you won't have the most competitive kit for the target comps so you will need to rely on your skill more?

 

Russ

[patjack]

something 6.5ish!!!

 

.260 or 6.5x47Or maybe the 6.5 creedmoor.

[ejg223]

I presume the result will be a compromise.

Finding the right end of the compromise is the key.

 

I had built myself a heavy border barrelled 243 23" 1/10 sitting in an ultra light carbon E-Tac.

This rifle weighed 5.7 kg including bipod and heavy Kahles tactical scope.

With little wind she shot very well at a 600yds comp, was just light enough to take stalking into the hill

and also doubled as my long range fox rig.

I sold this rig now as I would like to build something that is better at longer ranges but lighter.

 

Carbon fibre barrels have always interested me but many claim they don't shoot. A friend of mine went through

the maths of a steel/carbon barrel recently and came up with a new steel core shape coupled with new fibre angles in the lay

up. His first test barrel is shooting extremely well even compared to his match rifles. I had a similar method in

mind with a few more tricks and would try to make myself one too if time allows.....

Calibre wise I was between 22-250 1/7 with 80 - 90gr or a simple 260.

Combined with an E-Tac that weighs under 1000grams we could end up in the 3kg Sporter weight class but with a straight

taper 30mm barrel.

For hunting and varmint a light 6.5-20x50 conquest would do and for target I could put a heavier scope on the rifle

and make myself a second ultra heavy cheek raiser which would add around one pound weight on the line of the bore

where it is most benefitial.

Hunting 8.5 lb and in target dress ~ 11 lb rifle.

edi

[brown dog]

 

Carbon fibre barrels have always interested me but many claim they don't shoot. A friend of mine went through

the maths of a steel/carbon barrel recently and came up with a new steel core shape coupled with new fibre angles in the lay

up. His first test barrel is shooting extremely well even compared to his match rifles. I had a similar method in

mind with a few more tricks and would try to make myself one too if time allows.....

 

Love to hear more about that Edi; the idea of a "heavy-but-light" barrel on an AW would be a nirvana!

[gun nut]

Interesting solution to an eternal problem Edi, can't wait to see how it turns out, keep us posted.

 

Mike

 

PS I'd lean towards the 260 personally.

[DaveT]

YEP, spot on.

 

 

+1 (260) most accurate round I have ever used.... use it for stalking and target.

[achosenman]

I presume the result will be a compromise.

Finding the right end of the compromise is the key.

 

I had built myself a heavy border barrelled 243 23" 1/10 sitting in an ultra light carbon E-Tac.

This rifle weighed 5.7 kg including bipod and heavy Kahles tactical scope.

With little wind she shot very well at a 600yds comp, was just light enough to take stalking into the hill

and also doubled as my long range fox rig.

I sold this rig now as I would like to build something that is better at longer ranges but lighter.

 

Carbon fibre barrels have always interested me but many claim they don't shoot. A friend of mine went through

the maths of a steel/carbon barrel recently and came up with a new steel core shape coupled with new fibre angles in the lay

up. His first test barrel is shooting extremely well even compared to his match rifles. I had a similar method in

mind with a few more tricks and would try to make myself one too if time allows.....

Calibre wise I was between 22-250 1/7 with 80 - 90gr or a simple 260.

Combined with an E-Tac that weighs under 1000grams we could end up in the 3kg Sporter weight class but with a straight

taper 30mm barrel.

For hunting and varmint a light 6.5-20x50 conquest would do and for target I could put a heavier scope on the rifle

and make myself a second ultra heavy cheek raiser which would add around one pound weight on the line of the bore

where it is most benefitial.

Hunting 8.5 lb and in target dress ~ 11 lb rifle.

edi

 

Even the Gemans are looking at ways to save weight. Click

 

I’ve never seen any evidence of the accuracy of these barrels. I suspect they’re horribly expensive.

 

ATB

[terryh]

Ejg223

 

Always been an interesting take on the design of barrels, Remington fitted some of the Christienson CF wrapped barrels years ago, I remember being handed one and amost throwing it up in the air - expecting a much heavier rifle when you looked at the size of the barrel

 

Obviously people are dabbling with this concept, wrapping a liner with CF but here are a couple of questions to you that always come to my mind from and engineering point of view.

 

CF has a lower thermal conductivity compared to steel and an even greater difference compared to aluminium - does this not trap heat in on multiple shots?

 

CF has a lower coeficiant of expansion due to heat compared to steel, so if the steel liner is getting hot and trying to expand but the CF subjected to the same heat will expand less does that result in the 'bore' of the liner becoming smaller - as there is nowhere else for the liner material to go?

 

Possibly a simplistic view as there is obviously a lot to laying up and materials technology.

 

Also if you were going for light weight and heat critical in the rifle concept then I'd go for the 6.5x47 very similar performance to the 260 but with less power = less recoil and less heat into the barrel.

 

Brgds Terry

[ejg223]

Ejg223

 

Always been an interesting take on the design of barrels, Remington fitted some of the Christienson CF wrapped barrels years ago, I remember being handed one and amost throwing it up in the air - expecting a much heavier rifle when you looked at the size of the barrel

 

Obviously people are dabbling with this concept, wrapping a liner with CF but here are a couple of questions to you that always come to my mind from and engineering point of view.

 

CF has a lower thermal conductivity compared to steel and an even greater difference compared to aluminium - does this not trap heat in on multiple shots?

 

CF has a lower coeficiant of expansion due to heat compared to steel, so if the steel liner is getting hot and trying to expand but the CF subjected to the same heat will expand less does that result in the 'bore' of the liner becoming smaller - as there is nowhere else for the liner material to go?

 

Possibly a simplistic view as there is obviously a lot to laying up and materials technology.

 

Also if you were going for light weight and heat critical in the rifle concept then I'd go for the 6.5x47 very similar performance to the 260 but with less power = less recoil and less heat into the barrel.

 

Brgds Terry

 

Terry,

generally I don't really like the idea of mixing steel and carbon as a barrel material.

There have been just too many reports about bad accuracy and as you have pointed out the

problems with physics.

I am trying to figure out what others have done wrong or how one could improve.

Maybe previous efforts were trying too hard, trying to save too much weight.

Meaning one would have to have a good look at the steel blank and maybe edge to the safer side.

 

There are a few different types of carbon fibre. HS, HT or intermediate. Choice must be made wisely.

I'm guessing that most barrels are wrapped with a lathe type machine wrapping a single

roving in calculated angles. This method is very limited in fibre orientation and can be improved on.

 

Heat transfer: two ways looking at this:

Some say a warm barrel is a good thing, and newer match rifles are working on the principle of

containing heat not transfering it away. It is commonly known that hot barrels wear faster

than cold barrels....this is being disputed by many in the know. Tests have shown that accuracy

has held up much longer with hot fired assault rifles than with single cold shot rifles. Machine guns

have much higher shot counts than cold shot rifles. It has to do with stiffness being much higher

at colder temp leading to more heat cracks in the bore when heating and cooling off.

 

The other is, epoxy/carbon structure has a large part of its volume being epoxy resin which has a very low heat conductivity.

This I can change and without adding to volume. I am thinking of adding ultra fine or even nano materials

to the resins that change the thermal conductivity as we do already in our bedding of stocks.

This can dramatically change overall heat conductivity of the barrel.

 

I don't have the figures at hand but I think to remember alu on steel has a larger heat expansion gap

vs carbon on steel.

 

 

edi

[smokin]

just an aside edi , but did you ever see the carbon sleeved barrel Remington used to do ?

a friend once had one in 22-250 and it was incredibly accurate and very lite , looked the broccoli as well !

[brown dog]

Even the Gemans are looking at ways to save weight. Lothar Aluminium Sleeved Barrel

 

I’ve never seen any evidence of the accuracy of these barrels. I suspect they’re horribly expensive.

 

ATB

 

They look interesting; what's the engineering take on AL sleeving? I notice Lothar mention that the thing dumps heat. All good?

 

Anyone able to roughly price such a barrel in 6.5x47 or 308?

[gbal]

Hi guys need some advise on choosing a calibre and set up for shooting different dissaplines like mcqueens, fclass or open fclass, benchrest, long range vermin plus deer stalking so dont want it too heavy to carry. My max distance i want to shoot is up to 600yards as i feel that this distance is far enought for me atm but would try 800 yards in time.

 

 

Regards James.

Calibre is relatively easy:308 win is pretty good at most,though perhaps master at none-but what is? Better is 260Rem,or 6.5x47 Lapua,all you need certainly for 800yards.There are of course others-but these three are very sound,and 308w qualifies for FTR F class(with 223.) But one rifle is another matter entirely -there is a very good reason that Bench Rest and F class have 20lb plus or minus a couple of pound weight limits.They shoot better-much better.You will not be competitive with a stalkng rifle-you can shoot it,but be resigned to being in a different league.It's not a matter of skill-and in any case the 'proper' shooters will have more skill than you.A carry rifle does not really want to be more than 9 lb.Scopes too simply reflect the differnt requirements-though a good variable-say a leupold 8.5 to 25 (or whatever else in that minimum class/mag takes your fancy)would do for both (though even so reticule would be a compromise).It's all a compromise-one reason if you like that a joiner does not have just one tool only ,let alone one chisel.No one has really ever solved this ''problem'' ,though there are some solutions that are better than others! If you want to fiddle within 308/6.5,look carefully at barrel twist rates to see what limits you will meet.You simply must ethically have the proper tool for shooting living things-only you can decide if a very heavy weight rifle is something you can carry,or whether a half minute of angle really is critical within a couple of hundred yards.The bench rest rifle won't be quite so impressive without all the stabilising rests etc.I'd get two-your accuracy rig,and a competent stalker,which you may well already have!The classic realistic 'African battery' was always three rifles,and that's not far out-you replace heavy game by bunnies,big plains game by targets ....But you can use the same calibre(strictly,and thankfully-chambering!a 223,eg,with a 1 in 7 twist is effectively a different stick to a 223 with 1 in 12). See the consensus advice-308w,260 rem,6.5 x47 Lapua (the latter two being a distinction without an effective difference)but it adds more choice of makes etc.If you get a 6.99x30 half a magnum,semi express,and it works,we'll all like to hear about it.

The much fabled 'man with one rifle' was in reality rather limited,the man with one chambering can make it!

Good and varied shooting.

[gbal]

Hi guys need some advise on choosing a calibre and set up for shooting different dissaplines like mcqueens, fclass or open fclass, benchrest, long range vermin plus deer stalking so dont want it too heavy to carry. My max distance i want to shoot is up to 600yards as i feel that this distance is far enought for me atm but would try 800 yards in time.

 

 

Regards James.

Sorry James,

Let me add that if you want to shoot 100/200 yard benchrest,admitedly a bit specialised,a good rifle in the three calibres will do maybe do take part in the 'factory' as was class,and has beeen done with some competitive success.But if you are serious there are only two choices:the 6ppc,and the SIH in any calibre.The SIH isn't new,and should really be refered to by its full SAAMI name:the ''Self Imposed Handicap''.The 6ppc is of course absolutely appropriate for vermin,and just nice to shoot.

[baldie]

They look interesting; what's the engineering take on AL sleeving? I notice Lothar mention that the thing dumps heat. All good?

 

Anyone able to roughly price such a barrel in 6.5x47 or 308?

 

Had a 100 .22lr barrels made by walther with ali sleeves when i worked at Rogers.

 

Most are having runner beans grown up them. The very worst barrels i have ever had the misfortune to see.

 

My lads Nerf gun was more accurate.

[brown dog]

Had a 100 .22lr barrels made by walther with ali sleeves when i worked at Rogers.

 

Most are having runner beans grown up them. The very worst barrels i have ever had the misfortune to see.

 

My lads Nerf gun was more accurate.

 

Dave, must be more to that than meets the eye, what's the 'why' behind the story?

[ejg223]

Dave, must be more to that than meets the eye, what's the 'why' behind the story?

 

One hears good and bad about the LW Alu.

I saw the early version and sleeving method. In the meantime they have solved

the sleeving differently and avoid stress.

I know of one very fat alu LW barrel in 260 that shoots extremely well.

edi

[baldie]

Dunno Matt, not one of them would shoot, worth a s hit.

 

The only walther barrels i,ve seen that were truly outstanding are the liners used in the Volquartsen carbon fibre barrels. These are a liner , threaded at each end to accept a breech section and a threaded muzzle end. They are screwed together with a carbon fibre tube between them. However, this takes place in a freezer, where the parts have been sitting until very cold indeed. When they are allowed to warm up, everything contracts, and the liners are drawn very tight. Only ever had one bad in several thousand, and it didn,t shoot. It also made a different noise upon firing. Guess what ? The caps were loose.