Question-6.5X55AI

[Laurie]

The cartridge that this argument applies better to is the SLR family. The 6.5mm slr takes a 260 shell, squares off the shoulders by pushing them back and you lose a grain or 2 of powder while getting a square shoulder and longer neck. It has often been said that the longer neck keeps heat off the throat...it makes sense but I haven't seen any real data showing it is more than a theory.

Being a fan of the 6mm SLR I've wondered about the 6.5mm version. I do like small to medium 6.5s and the SLR looks a very attractive option.

To me, common sense dictates that as you approach 50g of powder, fire cracking and leade growth will increase no matter what kind of whistles and bells you have on the case or Bones from a dead black cat you may have in your pocket. Perhaps cooler burning powders are your only salvation.

I burn more and more Viht N160 and N165 these days in my favourite cartridges. It's too early to know what it does for barrel life with my loads, but present indications look good. The biggest issue / problem with N165 in medium size cases is simply getting enough in! Just OK for 284 throated for bullets seated well out unless you want to hotrod the cartridge, but much too heavily compressed in 7mm-08 (long freebore) even in thin-walled / higher capacity Winchester brass.

 

[Ggmac]

Thanks for your help. Let me restate his question. Will the AI shoulder angle improve throat-barrel life? He's not looking for more velocity. He just wants to know if the shoulder angle will have less throat erosion with the AI.

The first time I heard about this theory was in an article in either shooters bible or gun digest yearly books . It was called turbulence point and compared the 6mm Remington's barrel life ( throat ) to the 243 . If my memory is correct , it was his experiment and was asking for data to support or nix his idea .
Stick with the original, I like the Ackley but it can be more expensive to get up and going for no real advantage for him

 

[butchlambert]

Kinda mirrors my thoughts. I have a barrel going across the Atlantic for him in July. He does have reamers to do it either way. I'm sending him all your thoughts, even the red apple guys thoughts for "grins". Gert will make up his own mind and live with it.

 

[Liven The Dream]

A little facts .
Built a .260 AI Fire Forming wastes Barrel life .. theses are long range prone Rifles 1000 yard toys. 1800 rounds and set it back .
Went to straight 6.5X55 better Vol. than .260 AI. Barrel life 1860 ?
Small hole , Big Burn = short Barrel Life .

 

[ebb]

I have a Remington 700 that when I got it, it had a rechambered 300win mag barrel that was cut to be a 300 Jarrett. Ggmac replaced it after we borescoped it and found fire cracking 6 inches out toward the chamber. The Jarrett case has all the AI improvements. So if my barrel was ruined out to 6 inches from the chamber how does a square shoulder and long neck stop the over the top flame temp when it ruins barrels 6 inches from the chamber? If the flame was hot enough to crack the barrel way out there what happens at the neck must not have much consequence. I was at the WPB gun show today and was looking at powders. I wanted some Hybrid 100V as it has one of the lowest flame temps going. None in stock. I have used VV165 in my 6.5-284 since almost new. As I recall H1000 vv165 and hybrid 100V were all near the bottom of the list for flame temp. I think to extend barrel life any significant amount, all factors will have to be incorporated in to the gun, cartridge design (over bore),cartridge design (neck shoulder design), barrel steel, flame temp, bullet length and speed.

 

[MTSLW]

I've shot out a few barrels in a 6.5 Addiction, which is a 6.5x55 Imp 37* shoulder. I've had barrels that shoot well past 1.5K rounds at higher speeds with good accuracy. It was designed for a short action so not quite the powder capacity of a LA. I've used RL 26 almost exclusively. Fireforming isn't tough you're going to shoot a couple hundred rounds to break the barrel in any way so you might as well form brass while you're at it

 

[1shot]

I suppose that it’s possible if you insist on trying to get 6.5x284 velocities out of 6.5x55 versus 6.5 x55 AI.

It is very possible. I shoot a 6.5 GWI (Greg Walley Improved) the body has been blown out and it has a 30* shoulder. I get excellent accuracy at 3,050 ish FPS with 150 SMK's. I've had it over 3,100 but it's tough on the brass.
I hope this helps,

Lloyd

 

[moondog]

I'm following this with interest. I have 2 barrels spun up for a long action in the GWI.
version. I love developing loads and prepping brass. For whatever reason, I HATE trimming brass every time I shoot. Ran into this with Nosler 7SAUM brass. I'm looking forward to shooting this caliber. Not planning on pushing hard though.

 

[butchlambert]

My buddy, being from South Africa, has some limitations that we do not have. He does gunsmithing and has reamers for both 6.5X55 and 6.5X55AI. Gert has decided to chamber it in the non-ackley and in the future set it back and make an ackley out of it.
Thanks again for the responses about barrel life.

 

[2thdk]

It is very possible. I shoot a 6.5 GWI (Greg Walley Improved) the body has been blown out and it has a 30* shoulder. I get excellent accuracy at 3,050 ish FPS with 150 SMK's. I've had it over 3,100 but it's tough on the brass.
I hope this helps,

Lloyd

What twist are you running? I have a barrel chambered in Kelby's 6.5 GWI which is throated for a short action. Haven't shot it yet. Is this the same reamer you used to chamber your GWI?

 

[1shot]

I'm running a Bartlien 7.5 twist in the 5R configuration. I chose this specifically to shoot the 150 SMK's and it's working well. I regards to your reamer, Kelbly's has a reamer with a .002 tighter neck that the originator of the cartridge Greg Walley does. Other than that, they are identical. Do you know what neck you have?
I hope this helps,

Lloyd

 

[chop house]

I haven't spent any time on the 6.5x55 but I guess I should, it's the trendy cartridge now.

well, for once i am ahead of the times.... or, am i so far behind i am ahead?

 

[chop house]

*so far behind i only appear to be ahead....

 

[2thdk]

I'm running a Bartlien 7.5 twist in the 5R configuration. I chose this specifically to shoot the 150 SMK's and it's working well. I regards to your reamer, Kelbly's has a reamer with a .002 tighter neck that the originator of the cartridge Greg Walley does. Other than that, they are identical. Do you know what neck you have?
I hope this helps,

Lloyd

.298

 

[1shot]

I have the same chamber. Kelbly's also has a .296. My first couple of barrels were that neck. Honestly, I can't tell any difference,

Lloyd

 

[ebb]

Butch if he is worried about barrel life just send him 2 barrels. The rifle I sent to the Col. I sent 2. Its always nice to know that there is another just waiting in the safe should you need it.

 

[butchlambert]

Butch if he is worried about barrel life just send him 2 barrels. The rifle I sent to the Col. I sent 2. Its always nice to know that there is another just waiting in the safe should you need it.

Not a problem, if Gert wants 2. All it will cost him is twice what he owes now.

 

[Bill K]

A friend is considering a 6.5X55AI over the standard 6.5X55. He is thinking of doing this because he was told the shoulder angle would give him more throat life in his barrel. He doesn't care about extra velocity.
What are your thoughts?

Although there is some truth to that, has to do with the way the powder burns in the throat area, it is probably so minor, it is not worth worrying about. He will gain a few FPS, but mostly better case life with the AI shoulder, due to less lengthening of the brass in firing.

 

[ChrisNZ]

.. I can say my 6.5x55 AI gave me 6.5 x 284 velocities and an accurate barrel life less than 900 rounds. ... an example of there is no free lunch. ..

That is exactly the the experience of my (now deceased) gunsmith. He campaigned a BJ Ackley Swede and the barrels were toast before 1000 rounds

 

[rardoin]

That is exactly the the experience of my (now deceased) gunsmith. He campaigned a BJ Ackley Swede and the barrels were toast before 1000 rounds

He must have been running them faster than mid 2900 fps with a 140gr class bullet. My best barrel has just north of 1800rds and shot a 998-63X on it's last outing; the borescope does say it is 'on hospice care' at this point though. I run a 142gr/RL-23 at 2940 fps. I can't say that the improvement on the base case is responsible for the longevity.

Robin