6.5x55 vs 6.5/284

[243Mendoza]

Bodines is in PA, The Williamsport 1000 yard benchrest club is where we shoot...or did shoot.

OK, now I remember. I've heard that they conduct some fine NRA prone 1000yd matches. Wanted to attend but moved before I had the opportunity.

Hey, I admit it...it tried a 6.5x.284 for a year. HATED IT!

What did you hate about the 6.5-284?

 

[Bobthenailer]

flatlander, your velocities will drop off considerably after fireforming those Ackley cases..Ackley recomends aprox grains way over current book levels. I shot super tight fireforming groups with Sierra 85grn varminter bullets. I will run just under 3000fps and have sub 1/4" grouping with A.I. cases and 4831 powder stacked under Sierra 123grn match kings in my current rig. Keep us informed on your progress..

 

[cliffe]

how much less powder does the 6.5x55 swede or the ackley version use compared to the 6.5-284 at 2900-2950 fps with the 140 class bullets? also with the 6.5-284 what is the longest round count and still accurate you have heard of? thanks cliffe

 

[243Mendoza]

how much less powder does the 6.5x55 swede or the ackley version use compared to the 6.5-284 at 2900-2950 fps with the 140 class bullets? also with the 6.5-284 what is the longest round count and still accurate you have heard of? thanks cliffe

Accuracy depends on your type of competition and score/group expectations. For the 6.5-284 used for 1000yd NRA prone competitions, I expect half or better the 20 shots to go into the 1moa x-ring. I've had barrels with over 2000 rounds do this. For 600yd, I've had a barrel with 3500 rounds put over 75 consecutive rounds into the 2moa 10-ring or 1moa x-ring.

 

[rhino]

I don't really need to trim that much. I think once every 3-4 firings maybe even 5 firings. Custom Chamber Mimimal SAAMI spec with .294 neck.

Velocity is 2950 with 47.6 grains of VIN N560 using Tungston coated 140 gr berger vlds. Your running 6-8 grains less case capacity and I think the AI is 3-4 grains less...so you basically split the difference.

I never run them till gone. Couple years and rebarrel. I think 2000 with match grade accuracy is doable and many 6.5x.284 rebarrel at 1k.

Yes your mileage will vary.

I though about the ACKLEY, but if you go ackley why not just go 6.5.x.284 and not have to mess with fire forming.

So I went straight swede and it seems to shoot dam good.

RHINOUT!

 

[RichAllen]

I have two 6.5x284 Shehane rifles. The Shehane uses a 40 degree shoulder,Ackley) which allows you to push the 142 gr SMK to about 3100 fps.

It took two days and 120 cartridges to find a match winning load. I think the 6.5x284 is the round to beat at 1000 and IMO the 6.5x47 will be the round to beat at 600 in the very near future.

Rick

 

[rhino]

I have heard people shooting ackley's with the 40 degree shoulders have problems with the extractors breaking because the shells get stuck if you push them too hard.

I cannot comment on that myself, but I consider it a reliable source as I have shot and talked to him.

Now a 6.5x57 with like a 35 degree shoulder might be nifty.

RHINOUT!

 

[JHardy]

I have two 6.5x284 Shehane rifles. The Shehane uses a 40 degree shoulder,Ackley) which allows you to push the 142 gr SMK to about 3100 fps.

It took two days and 120 cartridges to find a match winning load. I think the 6.5x284 is the round to beat at 1000 and IMO the 6.5x47 will be the round to beat at 600 in the very near future.

Rick

Rick:

Respectfully, the 6.5x284 Shehane does NOT have a 40 degree shoulder. It keeps the original 35 degree shoulder and has less body taper per inch giving the case more capacity. It also keeps the already short neck of the 6.5x284 from being even shorter after a fireform to a sharper shoulder.

The 6.5x284 Super had the 40 degree shoulder,Shot by Bob Crone, Rich D., etc).

Jim

 

[RichAllen]

Jim,

I believe your right the shoulder isn't quite 40 degrees BUT the shoulder of the Shehane is considered to be Acklyized, at least that's how Shehane and others that use the chamber describe it.

I can't comment on the extractor problems as I'm the only person in my local area that uses the 6.5x284 Shehane.


Good shooting

 

[JHardy]

Rich:

It is a great chambering and I used it for a 10 match HG score agg in 2004, just missing an IBS WR. The gun also shot a HG group in the 4's. I have had several barrels in that chambering and Bill did a great job on the design.

If you hold a 6.5x284 case next to a fire-formed 6.5x284 Shehane, you will see that the shoulders are the same -- 35 degrees. Bill designed the case with less body taper so that he did not have to "mess" with the shoulder/neck. I promise you it is not an AI. To stir the pot a little more, the "Ackley" term applies not only to a 40 degree shoulder but also to the body taper that went with the Ackley case design. That might be the source of some confussion.

I also have a reamer for a 6.5x284 Rogue,37 degree shoulder) and you can easily see the difference between that fire-formed shoulder and the Shehane chambering.

Heck Rich, when all is said and done, it does not really matter because you have the loading setup that works and who cares what the specs are It is a great chambering.

I use a 7mm version of the same specs for my long range prone gun and it has shot rather well when I do my part. I can throw the 180 Bergers down range right with a 7mm RSUM -- 2950 to 3000 fps but with Lapua brass. Sweet. I have never had any extraction problems with a Shehane.

Just shoot and continue to have a great time because it is all good. When you see Bill at Hawks Ridge, he can fill you in -- a great shooter, friend and ambassador to the 1000 yd BR game.

Favor center,
Jim