6.5 comparisons

[Viking264]

All,
I've been running some comparisons between 6.5x55 (standard), 6.5x55 AI, 6.5-284, and .260 Rem (loaded in long action). I'd like to keep this thread confined to these cartridges (in other words, please refrain from interjecting recommendations of looking at the 6.5 CM, 6.5x47, 6.5-06, 6.5 Sherman, etc.). I will preface all of this by stating that I am primarily a shooter of .284 Win (long action) and 6.5x55. I also shoot a bit of .260 Rem.

Using QL to determine required mass of RL26 to propel a 140-grain ELD to 2950 fps, and then comparing the pressures generated, grains required, and so on, I see some interesting things, with same-length barrels:

.260 Rem (standard) has the highest ballistic efficiency, followed by the standard 6.5x55, then the 6.5x55 AI, and last the 6.5-284.

Lowest pressures were generated by the 6.5-284, then the 6.5x55AI, then the .260 Rem, and lastly the standard 6.5x55.

Mass of RL26 required to achieve 2,950 fps (as calculated by QL) was least with .260 Rem, then 6.5x55, then 6.5x55AI, and (most required was) 6.5-284.

Admittedly, I load my 6.5x55 to higher pressures than SAAMI or CIP, before someone asks.

I raise all of this because I have been toying with the idea of obtaining a 6.5-284 barrel for one of my rifles. So much has been written on the web about horrendous barrel life of this cartridge, I figured I'd look at pressures. For a 26" barrel, 50,979 PSI. I'm thinking that the barrel life can't be that bad. Assume not shooting rapid fire and letting the barrel cool; am I wrong? At that pressure, would I not be expecting higher round count than 1K?

I must say that I was surprised at the results with the .260, by the way.

 

[toddc]

Lots of ways to skin a cat with a 284 based rig.
Surprised that the load only generates 50k but RL26 isn't old school 4831.
I have burned up quite a few 6.5-284 barrels and with the better steels and better powder around today they will last longer.
I went to the slower stuff like Retumbo and H-1000 since the 90 and they definitely live longer and RL26 is possibly going to yield even better results.
A lot of the barrel smoking was related to running faster powders to reach 3K+.
With the newer stuff available every cartridge is a NEW CARTRIDGE essentially. Things are being done with RL17 that we would have said you were nuts 10 yrs ago. Seems to be the same with many of these new powders.
RL17 and Superperformance as well as newer lots of H-1000 and W870 are doing things that have honestly made me think my chrono was broken, I was drunk or about to blow my head off.
A larger case such as the 284 should LOAF more to reach a reasonable velocity and should therefore protect a throat better than a higher pressure, smaller case no matter the design.
And truthfully I would call the 284 the best design of everything you mentioned anyway. The 260 is about 10 yrs older than the 284 and the Swede....well its older than dirt lol.
I built a 22 and a 6 built on the 284 since 05 or so and both lasted better than I expected running the heaviest VLDs I could find with Retumbo and not trying to be a speed demon.

 

[Michael Eichele]

I use to subscribe to the notion that running a 6.5-284 easy, cool between shots etc...would yield great barrel life. After trying that, I still had to set the barrel back at 450 rounds and again at 600. I gave up hope at 750. I'll still shoot under .7 MOA at 800 rounds but it's frustrating to watch a barrel that would shoot in the .1s and .2s most days and .3s and .4s on its worst days (rarely) and then open up to north of .5. Plus the charge weights had to be altered every so often to accommodate a flame cut throat. I babied that barrel from shot one and it still deteriorated at a high rate. Anymore, I'm happy with a larger bore and a little more recoil in exchange for better barrel life.

Just MHO and point of view.

M

 

[WildRose]

All,
I've been running some comparisons between 6.5x55 (standard), 6.5x55 AI, 6.5-284, and .260 Rem (loaded in long action). I'd like to keep this thread confined to these cartridges (in other words, please refrain from interjecting recommendations of looking at the 6.5 CM, 6.5x47, 6.5-06, 6.5 Sherman, etc.). I will preface all of this by stating that I am primarily a shooter of .284 Win (long action) and 6.5x55. I also shoot a bit of .260 Rem.

Using QL to determine required mass of RL26 to propel a 140-grain ELD to 2950 fps, and then comparing the pressures generated, grains required, and so on, I see some interesting things, with same-length barrels:

.260 Rem (standard) has the highest ballistic efficiency, followed by the standard 6.5x55, then the 6.5x55 AI, and last the 6.5-284.

Lowest pressures were generated by the 6.5-284, then the 6.5x55AI, then the .260 Rem, and lastly the standard 6.5x55.

Mass of RL26 required to achieve 2,950 fps (as calculated by QL) was least with .260 Rem, then 6.5x55, then 6.5x55AI, and (most required was) 6.5-284.

Admittedly, I load my 6.5x55 to higher pressures than SAAMI or CIP, before someone asks.

I raise all of this because I have been toying with the idea of obtaining a 6.5-284 barrel for one of my rifles. So much has been written on the web about horrendous barrel life of this cartridge, I figured I'd look at pressures. For a 26" barrel, 50,979 PSI. I'm thinking that the barrel life can't be that bad. Assume not shooting rapid fire and letting the barrel cool; am I wrong? At that pressure, would I not be expecting higher round count than 1K?

I must say that I was surprised at the results with the .260, by the way.

I've shot the Swede, .260Rem and .264wm. It's really hard to be the .260 in the all around which is why I now have three of them. One AR, one Ruger FTW Edition, and One Remington 700 Gen 2 5R. The AR has decent accuracy even after more than 1500 Rounds and the Ruger and Remington have both seen heavy use this season both on game and on Paper and I like them better every time I pull the trigger.

You can extend your barrel life on any caliber by simply not shooting it hot and keeping on shooting it.

Shoot a 3 round group and let it get back pretty close to ambient outdoor temp before shooting the next group and do it every time and you'll be hard pressed to ever shoot one out assuming you are starting out with a quality barrel.

Break the barrel in good, clean it completely and send it off to have it melonited or otherwise heat treated and you'll extend it even further.

Of all the 6.5's if I wasn't shooting the .260Rem I'd probably move to the 6.5-284 but unless I find myself in the middle of a prairie dog town or invasion of pigs I probably won't ever shoot more than a handful of rounds on any given trip because frankly, if I do my part the .260 has been the most efficient "one shot one kill" rifle I've ever had.

The wife and I together put 8 deer and four hogs, including one rather large boar in the freezer firing a total of 12 shots at all of them. That total is split between the Ruger and the Remington.

The mild recoil is a problem though because it makes you want to keep shooting even when you're already sighted in and have verified your drops at several ranges.

 

[codyadams]

I know this is slightly different, but I have a .260 AI, and absolutely love it. I'm at 800 rounds and my throat has hardly changed, and acuracy is consistently in the .2's. My current load is running a over a full grain under max and still going 2930 w/47.8 grains with a 140 vld, my max is 3015 or so with 49 grains. This is with H4831sc.

Tomorrow I will be testing some loads with the 147 ELD-M and reloader 26, I worked my loads up starting at 48 grains and ending at 50.5 grains, moving in .5 grain increments. If your interested, let me know and I'll post my results. I myself couldn't find any data whatsoever on a .260 AI and reloader 26. I even emailed alliant as well as hornady, and they offered nothing.

 

[Greyfox]

While I don't doubt the experiences that shooters have had with short barrel life with the 6.5x284, but I have not experienced barrel life much different from many of the usual calibers capable of delivering comparable ballistic performance for LRH and subjected to the same operating parameters. Two of my 6.5x284's used exclusively for LRH are going on 8 years old and are running over 1000 rounds each. There has been no material change in bullet seating depth to the lands, accuracy(.2-.4MOA), velocity, or ES. These values have been religiously measured each year since initial load development was completed. Both rifles have been loaded with Lapua brass, 58gr, Retumbo, Fed210M, seated .075" with 140 Berger VLD Hunting and 140 JLK's. Neither rile has ever been shot hot, and have been thoroughly cleaned every 50-75 rounds, about a seasons worth of shooting/hunting. Velocity of this load is 2975FPS. I expect both rifles to give me about 1200-1500 rounds before I see degradation of .25-.5MOA, about what I have seen with the 7mmMag and 300WM. My 270WSM and Weatherbys did not make 700 rounds. My 260Rem, and 308's which are used for competition and run very hot in the summer months give up the ghost at 2200-2500 rounds.
All said, I have been very impressed with the 6.5x284's performance given the numerous animals my rifles have accounted for at long range over several years. If they crapped out tomorrow, I couldn't complain. I have a just completed a great new build that's in the wings, just in case. What's spooky is that at my age, it just might outlive me.

 

[J E Custom]

I know this is slightly different, but I have a .260 AI, and absolutely love it. I'm at 800 rounds and my throat has hardly changed, and acuracy is consistently in the .2's. My current load is running a over a full grain under max and still going 2930 w/47.8 grains with a 140 vld, my max is 3015 or so with 49 grains. This is with H4831sc.

Tomorrow I will be testing some loads with the 147 ELD-M and reloader 26, I worked my loads up starting at 48 grains and ending at 50.5 grains, moving in .5 grain increments. If your interested, let me know and I'll post my results. I myself couldn't find any data whatsoever on a .260 AI and reloader 26. I even emailed alliant as well as hornady, and they offered nothing.

+1
This would be My recommendation also because it has all of the benefits that you want. Velocity,
accuracy, brass life, works on a short action, barrel life is very good because of cartridge design.

Just My Opinion

J E CUSTOM

 

[Viking264]

I would be interested in seeing your results on your .260 Rem AI with the 147's. QL has no data on this cartridge.

FWIW, I am not convinced that there is any advantage whatsoever to running a short action. Improved speed chambering the next cartridge is insignificant, supposedly stiffer action is also insignificant in terms of accuracy (this statement is based upon the fact that so many European competitive shooters are still using the 6.5x55 and are successfully competing with military shooters using HK semi-auto rifles chambered in 7.62x51, and the fact that the 6.5-284 was, according to Norma USA, designed as a long-action cartridge). My only interest in the .260 is that it shoots a .264, but I would not have interest in shooting it in a short action due to the decreased case capacity relative to the 6.5x55. In a long action (110), I'm loading my .260 Rem to a COAL of 2.933 (using the 140 ELD). In my case, this is a result of having purchased the 110 with a custom barrel in .260 Rem. The long action enables the potential of the cartridge to be reached; same goes for .243 Win and any other short-action-designed cartridge, for that matter. The .260 Rem in a long action is much closer to the potential of the 6.5x55 (which I run to ~58K PSI with modern actions). The departure between the two occurs, for me, when using the 156- and 160-grain hunting projectiles, where I believe the 6.5x55 is more suitable. The reason that more competitions are not won with the 6.5x55 here in the States is, I am certain, a self-fulfilling prophecy: few people (almost none) are using them in these competitions. Take the top shooters in 6.5-284 and hand them a good 6.5x55, and they will keep winning with the only modification being adjustment of their turrets. [As an aside, I cannot for the life of me understand why someone would have interest in the 6.5 CM, but that's another thread. If you want lower velocity and "more inherent accuracy", then maybe the 6.5x47 is the ticket (I have only barely read about this, so who knows). Hornady is now selling .260 brass, by the way, in line with their factory production .260 Rem cartridges to make use of all of the new 6.5mm projectiles that they developed for use in the 6.5 CM.]

I AM NOT taking anything away from the performance of the .260 Rem loaded in a SA as a hunting or target cartridge; clearly, it works extremely well in so many circumstances. Since I only run it in LA, I didn't bother looking at figures on QL when loaded to the shorter COAL. What I am seeing from the figures shows me that the 6.5-284 doesn't really offer much in the means of overall performance. I love the case design; I am probably now 60/40 shooting the .284 Win (again, in long action) vs. the 6.5x55, but I think that's where my interest in the 6.5-284 ends. Running these figures on QL has been an interesting and enlightening exercise. What it will likely lead to is my loading the .260 Rem with 127-grain LRX and 130-grain HPBT (Norma) for hunting and target, respectively, and the 6.5x55 with the same Barnes hunting round and 140-grain ELD for target.

 

[toddc]

While I don't doubt the experiences that shooters have had with short barrel life with the 6.5x284, but I have not experienced barrel life much different from many of the usual calibers capable of delivering comparable ballistic performance for LRH and subjected to the same operating parameters. Two of my 6.5x284's used exclusively for LRH are going on 8 years old and are running over 1000 rounds each. There has been no material change in bullet seating depth to the lands, accuracy(.2-.4MOA), velocity, or ES. These values have been religiously measured each year since initial load development was completed. Both rifles have been loaded with Lapua brass, 58gr, Retumbo, Fed210M, seated .075" with 140 Berger VLD Hunting and 140 JLK's. Neither rile has ever been shot hot, and have been thoroughly cleaned every 50-75 rounds, about a seasons worth of shooting/hunting. Velocity of this load is 2975FPS. I expect both rifles to give me about 1200-1500 rounds before I see degradation of .25-.5MOA, about what I have seen with the 7mmMag and 300WM. My 270WSM and Weatherbys did not make 700 rounds. My 260Rem, and 308's which are used for competition and run very hot in the summer months give up the ghost at 2200-2500 rounds.
All said, I have been very impressed with the 6.5x284's performance given the numerous animals my rifles have accounted for at long range over several years. If they crapped out tomorrow, I couldn't complain. I have a just completed a great new build that's in the wings, just in case. What's spooky is that at my age, it just might outlive me.

There is 1 word in this post that explains most of it......RETUMBO. The 6.5-284 SHOULD have been run forever with powder in this class but it wasn't. Jump up 15 places in burn rate AND.......bye bye barrel.
This one more example of powder advances changing the game in cases.

 

[jakelly]

If I wanted a SA, then I'd go 260 AI. If I wanted a LA, and 6.5-06AI was off the table, I'd go 6.5x55 AI.

 

[Danehunter]

I have two 6.5 Creedmoor rifles, Ruger Amer. Predator for hunting and Ruger Precision Rifle for competition. I am very satisfied with with both because they shoot fairly flat, are not barrel burners and seem inherently accurate. PLUS the case is designed to handle long VLD type bullets, something the 260 Rem. will not do without a lot of powder compression and dangerous pressures.. If it would have handled VLD bullets there would have been no need to develop the 6.5 CM.

But... for really flat shooting 6.5 pills the 6.5/284 is it. Yes, at 3,000 FPS plus muzzle velocities it's a barrel burner but it is just so flat shooting and accurate.

A similar round would be a 6.5 Swede AI. The Ackley Improved case gives a lot of room for powder and there are dies made for it by specialty die makers like Jones Precision in Pennsylvania. Of course you have to form your own brass but it's not difficult.

Eric B.

 

[codyadams]

I have two 6.5 Creedmoor rifles, Ruger Amer. Predator for hunting and Ruger Precision Rifle for competition. I am very satisfied with with both because they shoot fairly flat, are not barrel burners and seem inherently accurate. PLUS the case is designed to handle long VLD type bullets, something the 260 Rem. will not do without a lot of powder compression and dangerous pressures.. If it would have handled VLD bullets there would have been no need to develop the 6.5 CM.

But... for really flat shooting 6.5 pills the 6.5/284 is it. Yes, at 3,000 FPS plus muzzle velocities it's a barrel burner but it is just so flat shooting and accurate.

A similar round would be a 6.5 Swede AI. The Ackley Improved case gives a lot of room for powder and there are dies made for it by specialty die makers like Jones Precision in Pennsylvania. Of course you have to form your own brass but it's not difficult.

Eric B.

I have to somewhat disagree with your statement on .260 short actions won't handle vld's....im shooting 140 vld's at .005" off lands and they still fit in my Wyatts detachable mag at 2.875" OAL. And I just shot some 147 eld-m's today, and they shot best at .050" off, which is 2.865". I got some OUTSTANDING performance...I'll post it later tonight with pictures.

 

[TA1911A1]

Subscribed. I like the thought of the 260 AI in long action. I have been wondering what to do with my left hand 300 RUM since I purchased my 338 Edge. Was thinking of a 6.5-06 AI but it can be a little hard on a barrel.

 

[Viking264]

If I was going to re-barrel an existing long action, then I would really be looking hard at the 6.5x55mm AI. There is such an abundance of quality once-fired and new brass available for considerably less than any other 6.5-caliber cartridge. I have been getting once-fired Norma from a guy in Sweden for something like $0.25 each. Even new Lapua in 6.5x55 is less expensive than other 6.5-cartridges (because they produce so much of it for competitive shooting in Sweden and Norway). This is the route that I will go once I have pulled the existing barrel off of my T3 Sporter.