6.5x55 SE or 6.5-06?

[jbronner13]

I was in the Weatherby shop a few weeks ago and talked with an engineer/ballistician.

I have a 9 lug Accumark ULW in .243 Win. Long time coyote calling rifle.
I also have a WBY factory takeoff .338-06 A-Square barrel from a 9 lug Super Big-game Master.

We discussed the barrel swap options of the two and I inquired about the 6.5 RPM and .338 RPM option.

The larger diameter RPM case requires more machining to the under side of the action to make room for the cases in the magazine box and effectively makes the barrel swap option in my case untenable to the RPM. I'll be going with the factory takeoff .338-06 A-Square barrel when the time comes.

He showed me the underside of both rifle calibers, Standard/RPM so I could see the difference.

Thought I'd share so the OP would have info on additional modifications to his action required if he went RPM.

That's very useful info and something i definitely didn't know nor would have even considered.

Also, Airedales are awesome dogs, probably why The Duke owned them exclusively.

 

[Airedale56]

My Purdy dog was a coyote-killing maniac.
She hated them with a passion.
Best decoy dog I've ever had.
RIP, Purdy.
That pic was an early morning stand. We got three on it.

 

[Litehiker]

Neither: Get a 6,5 PRC.

 

[Jerry M]

Neither: Get a 6,5 PRC.

Not an economical use of a Pre-64 model 70 with a standard boltface.

 

[jbronner13]

Not an economical use of a Pre-64 model 70 with a standard boltface.

Bingo

 

[Litehiker]

Change the boltface. Get a custom bolt.

 

[Outlaw6.0]

6.5x06 - same boltface, same body size as 30-06 so no modifications needed to the magazine rails, same overall length, so no feeding worries. Run a .25-06 casing through a 6.5-06 die and load, easy peasy.

That's exactly what I do, then fireform to AI of course

So obviously I have to vote 6.5-06AI. Of course, the nostalgia we all keep talking about would also vote for the Swede (AI), especially from that Mod 70 action.

Perhaps flipping a quarter would work? lol Sometimes we just have to let fate decide, it could surely save you a headache.



t

 

[cdherman]

I have a 6.5x284 and 6.5x55 SE.

Suspect the OP has made up his mind by now. Anyhow, in a modern action you can really push the Swede, but you better have Quickload and be willing to try and decide whether you are seeing pressure signs. Not a lot of book data, and in USA especially so, since the loading manuals are very conservative. I am right at 2950 with 143 ELDx in a Tikka T3 Lite. 20" barrel. Poppin for a little gun.

I have a 6.5x284 too. Takes a standard bolt face and loves a longer action. But there was comment about the ejector. It would be my choice for quality brass (Lapua) in a 6.5 build with standard bold face. My 6.5x285 is running the 156 Berger pretty fast too. Nice to have published data.

6.5-06 will make you buy expensive brass or form bass etc. And it is not a bit superior to the 6.5x284 (basically identical case capacity). And with the 6.5-06 or AI, you are going to have to work up loads on your own.

In the end, IMHO, the choice starts with: Do I want to work up loads based on a lot of research/Quickload/observation?

No -- 6.5x284

Do I have an itch for a classic cartridge and I'm willing to work up loads? yes? Swede!!!!

Do I have an itch for nearly max 6.5mm performance in a classic LA Win action with minimal mods? 6.5-06. But gotta be willing to deal with brass forming, no load data in books, etc....

Of course there are lots of other 6.5 stuff out there these days. None will have more loading support than the aforementioned, some might be even hotter. Dunno. I have no first hand experience. I like my Swede and 6.5-284 both. Considered a 6.5-06 but went with 280 AI for a different gun since I have too many .264 already.....

 

[jbronner13]

I have a 6.5x284 and 6.5x55 SE.

Suspect the OP has made up his mind by now. Anyhow, in a modern action you can really push the Swede, but you better have Quickload and be willing to try and decide whether you are seeing pressure signs. Not a lot of book data, and in USA especially so, since the loading manuals are very conservative. I am right at 2950 with 143 ELDx in a Tikka T3 Lite. 20" barrel. Poppin for a little gun.

I have a 6.5x284 too. Takes a standard bolt face and loves a longer action. But there was comment about the ejector. It would be my choice for quality brass (Lapua) in a 6.5 build with standard bold face. My 6.5x285 is running the 156 Berger pretty fast too. Nice to have published data.

6.5-06 will make you buy expensive brass or form bass etc. And it is not a bit superior to the 6.5x284 (basically identical case capacity). And with the 6.5-06 or AI, you are going to have to work up loads on your own.

In the end, IMHO, the choice starts with: Do I want to work up loads based on a lot of research/Quickload/observation?

No -- 6.5x284

Do I have an itch for a classic cartridge and I'm willing to work up loads? yes? Swede!!!!

Do I have an itch for nearly max 6.5mm performance in a classic LA Win action with minimal mods? 6.5-06. But gotta be willing to deal with brass forming, no load data in books, etc....

Of course there are lots of other 6.5 stuff out there these days. None will have more loading support than the aforementioned, some might be even hotter. Dunno. I have no first hand experience. I like my Swede and 6.5-284 both. Considered a 6.5-06 but went with 280 AI for a different gun since I have too many .264 already.....

I'm actually still tire kicking and you just blew my mind and made my choice a lot more difficult

 

[FEENIX]

I have a 24 inch .264 Shaw Barrel with a 1-8 twist I purchased merely because it was on sale for a good price and I figured, "I can probably do something with it, I have a few donor actions lying around. I have decided to attach said barrel to a 1954 Winchester Model 70 action. I have all the parts just waiting on a stock. I am having a difficult time deciding what cartridge to chamber this rifle for….the 6.5x55SE or a 6.5-06. Wanted some feedback from folks here, I am looking for it to be a mule deer rifle for a western hunting trip. I will handload but I haven't ever handloaded for either of these cartridges and was wondering what a can expect from a ballistics standpoint from each cartridge using bullets in the 140 grain realm. I know the 6.5 Swede can be pushed higher than SAAMI specs from a strong action like a Model 70, how far can I push it and what can I expect to get for real world MV numbers for each cartridge running at a max or close to max pressure load?

I have a 6.5 CM, 6.5x55 Swede, and .264 WM. The 6.5x55 is a Carl Gustaf 18" barrel with which I started my sons hunting with. It is very accurate, and there is something nostalgic about the 6.5 x 55 Swede, just like our venerable -06. Good luck with your project build.

 

[nralifer]

I too vote 6.5-06' out of your choices, but suggest either Ackleyize the 06' or go straight 6.5-280 Ackley where you can simply neck down 280 Ackley SAMMI brass using 280 Ackley bushing dies, a 6.5 expander and run.

I certainly agree that the 6.5AI is an excellent LR cartridge, but to get there you will have to do some fire forming and brass availability of 280AI may be more limited than the Sweed brass. I would check that before making the decision. If you use a 7 twist barrel with either cartridge you can take advantage of the high BC bullets out there so MV becomes less important.

 

[Darryle]

I certainly agree that the 6.5AI is an excellent LR cartridge, but to get there you will have to do some fire forming and brass availability of 280AI may be more limited than the Sweed brass. I would check that before making the decision. If you use a 7 twist barrel with either cartridge you can take advantage of the high BC bullets out there so MV becomes less important.

Or you can have a reamer cut that doesn't require touching the shoulder, only requires neck sizing and use readily available 280 Ackley Sammi brass. 2 steps to 6.5 and 1 or 2 more to 25.

 

[FEENIX]

Or you can have a reamer cut that doesn't require touching the shoulder, only requires neck sizing and use readily available 280 Ackley Sammi brass. 2 steps to 6.5 and 1 or 2 more to 25.

Dave makes great reamers. He built two wildcat reamers for me.

Another option is to have a hydraulic forming die. John Whidden made mine.

 

[Darryle]

Dave makes great reamers. He built two wildcat reamers for me.

Another option is to have a hydraulic forming die. John Whidden made mine.

They were great to work with.

I don't think the hydraulic sizing die would work for me since I am simply utilizing a smaller bushing in the S Series bushing die, I actually have 2 bushing dies and simply swap between them to reach the correct neck size. I found out quickly you can be to aggressive with this process.