New Weatherby Cartridge 6.5 RPM

[Nomosendero]

The .264 Win Mag has a case capacity of 82 grams of H2O.

Based on the near-equal case volumes, it seems the 6.5 RPM will have ballistics almost identical to the .264WM, but in a more modern case design.

Not a bad place to be, I like my 264, I am looking forward to a build using my 270 M700.

 

[WeatherbyFan]

I was wanting a Weatherby Backcountry Ti 6.5 RPM, I got impatient waiting so had my gunsmith build one on a Kimber Montana 84L donor,
Gunsmith Gary Flach lengthened the mag box so we can load those 156 Bergers without issue, added an Alloy trigger guard, trigger set at 2.5lbs, 24 inch SS #2 contour 1-8 twist Benchmark Barrel, Black Gunkote on all metal surfaces, Gary used a yellow green for the stock with some multi coloured splatter, I opted for no brake so we will see how snappy this rig is as its not very heavy, 7lbs 3oz scoped with a Zeiss V4 4-16x44

Range Day #1 on the 6.5 RPM, I had a box of each of the factory ammo, these speeds out of a new 24" Benchmark Barrel, recoil was firm and straight back no terrible muzzle jump so was manageable, all shots at 100 yards.

140gr Interlocks advertised velocity 2975fps- actual 3030/3022 first two shots to zero, cleaned barrel then 3 more shots at 100 3002/2993/2982 producing 1.1" group.

140gr Accubonds advertised velocity 3075fps- actual from a clean barrel 3041/3013/3014, produced a .9" group

127gr LRX advertised velocity 3225fps- actual from a clean barrel 3103/3109/3093 produced a .6" group

Range Day #2 with the 6.5 RPM, I took a stab at where to start with R26 63.0/63.5/64.0/64.5/65.0grs, this started last time out at the range where my LabRadar was acting up so never got a velocity reading for 63.0/63.5 (3/4" groups), so stopped there and ordered a new LabRadar, so today was bit better.

6.5 RPM, R26, BR2 Primers, once fired Factory Wby (Hornady Brass) Berger 156gr Elite Hunters, COAL 3.410"

Clean barrel 64.0grs- 3045/3029/3031

I adjusted the scope and then shot the 65.0gr group, 3061/3072/3070

I ran a string up from my load of 65.0grs of R26/BR2 Primers, New Wby brass and 156gr Berger Elite Hunters

65.0-3068
65.3-3089
65.6-3108
65.9-3126
66.2-3145-slight tight bolt lift
66.5-3148-slight tight bolt lift and light ejector marks, I stopped there.

 

[jackson1]

Where's the belt?

 

[WeatherbyFan]

Where's the belt?

It’s holding my pants up

 

[STOMP442]

Pretty impressive accuracy from such a large cartridge and a long whippy barrel. Nice rig.

 

[Nomosendero]

Has any other Co. but Wea. started offering the brass?

 

[M14AMU]

Just another barrel burner! Wonder if they're still cutting freebore into their chambers??

 

[46and2]

Just another barrel burner! Wonder if they're still cutting freebore into their chambers??

 

[Ackman]

I used to have a .257 wby. It was fast but the long throat hampered my accuracy despite a krieger target barrel. If you have one built, get a custom chamber with a shorter throat.
Recoil was not bad at all. I used mine for deer in Texas and it was very effective If I wanted a small caliber long range hunting rifle, a fast 6.5 would be my choice due to a superior selection of bullets. Limit shot strings and don't try every bullet/powder combination. Barrel life will be plenty long enough for hunting for years to come.

A friend - Ackleyman II on here - built a few .257WBY's with 0 freebore and a shortened case length. I have one with that chamber. The shorter caselength is for forming .257 brass from less expensive and very good 7mm or 264Mag brass. My 257 cases are trimmed to 2.480"and with 0 freebore there's plenty of neck for the bullet. With good strong brass and a 26" barrel you can get 3850 with a 100 gr. bullet and do it very accurately. That cartridge works really well with no-freebore.

*** Edit: My own 257WBY has that chamber and a 29" - 12twist Hart barrel. The accuracy loads are 3980 and 4010 with 100gr Sierra bullets.

 

[AckleymanII]

I copied a friend that was a gunsmith in San Diego, but I shortened the neck when I found out that the double radius was formed perfectly every time when ran through a full length sizer. Accuracy is amazing stuffing the bullet down in the neck with 87,100, and 117-120g bullets. 264 Win mag and 7 Mag Winchester brand of brass works well. 87's run 4130 on a 26", 10T three groove, hair floated down for what seemed like 5 minutes with a few coyotes I shot, very humane kills.

Surprising, the 100g partitions shot 1/2" groups at 3850 out of a three groove Pac Nor barrel, took 9 rounds to work up the load.

I have never seen a deer take a single step after being hit with this kind of speed, with a muzzle break, you see the water vapor fly off the hide and watch them collapse.

A friend killed 6 big bull elk with his Mark 5 using factory ammo, then found out the 257 was not an elk rifle from a professional guide.

 

[Nomosendero]

I guess if the RPM is a barrel burner than I guess a person would be lucky to get a 26 Nosler sighted in before the barrel is toast!
For a hunting rifle, not a volume range rifle, I am not worried.

 

[Nomosendero]

Ackleyman, with that 100 Partition, what powder were you using?

 

[Hohn]

So we’re pretending that the 26 Nosler isn’t a thing? I mean if you want an overbore magnum 6.5...

 

[NCIowan]

I was wanting a Weatherby Backcountry Ti 6.5 RPM, I got impatient waiting so had my gunsmith build one on a Kimber Montana 84L donor,
Gunsmith Gary Flach lengthened the mag box so we can load those 156 Bergers without issue, added an Alloy trigger guard, trigger set at 2.5lbs, 24 inch SS #2 contour 1-8 twist Benchmark Barrel, Black Gunkote on all metal surfaces, Gary used a yellow green for the stock with some multi coloured splatter, I opted for no brake so we will see how snappy this rig is as its not very heavy, 7lbs 3oz scoped with a Zeiss V4 4-16x44

Range Day #1 on the 6.5 RPM, I had a box of each of the factory ammo, these speeds out of a new 24" Benchmark Barrel, recoil was firm and straight back no terrible muzzle jump so was manageable, all shots at 100 yards.

140gr Interlocks advertised velocity 2975fps- actual 3030/3022 first two shots to zero, cleaned barrel then 3 more shots at 100 3002/2993/2982 producing 1.1" group.

140gr Accubonds advertised velocity 3075fps- actual from a clean barrel 3041/3013/3014, produced a .9" group

127gr LRX advertised velocity 3225fps- actual from a clean barrel 3103/3109/3093 produced a .6" group

Range Day #2 with the 6.5 RPM, I took a stab at where to start with R26 63.0/63.5/64.0/64.5/65.0grs, this started last time out at the range where my LabRadar was acting up so never got a velocity reading for 63.0/63.5 (3/4" groups), so stopped there and ordered a new LabRadar, so today was bit better.

6.5 RPM, R26, BR2 Primers, once fired Factory Wby (Hornady Brass) Berger 156gr Elite Hunters, COAL 3.410"

Clean barrel 64.0grs- 3045/3029/3031

I adjusted the scope and then shot the 65.0gr group, 3061/3072/3070

I ran a string up from my load of 65.0grs of R26/BR2 Primers, New Wby brass and 156gr Berger Elite Hunters

65.0-3068
65.3-3089
65.6-3108
65.9-3126
66.2-3145-slight tight bolt lift
66.5-3148-slight tight bolt lift and light ejector marks, I stopped there.

I was wanting a Weatherby Backcountry Ti 6.5 RPM, I got impatient waiting so had my gunsmith build one on a Kimber Montana 84L donor,
Gunsmith Gary Flach lengthened the mag box so we can load those 156 Bergers without issue, added an Alloy trigger guard, trigger set at 2.5lbs, 24 inch SS #2 contour 1-8 twist Benchmark Barrel, Black Gunkote on all metal surfaces, Gary used a yellow green for the stock with some multi coloured splatter, I opted for no brake so we will see how snappy this rig is as its not very heavy, 7lbs 3oz scoped with a Zeiss V4 4-16x44

Range Day #1 on the 6.5 RPM, I had a box of each of the factory ammo, these speeds out of a new 24" Benchmark Barrel, recoil was firm and straight back no terrible muzzle jump so was manageable, all shots at 100 yards.

140gr Interlocks advertised velocity 2975fps- actual 3030/3022 first two shots to zero, cleaned barrel then 3 more shots at 100 3002/2993/2982 producing 1.1" group.

140gr Accubonds advertised velocity 3075fps- actual from a clean barrel 3041/3013/3014, produced a .9" group

127gr LRX advertised velocity 3225fps- actual from a clean barrel 3103/3109/3093 produced a .6" group

Range Day #2 with the 6.5 RPM, I took a stab at where to start with R26 63.0/63.5/64.0/64.5/65.0grs, this started last time out at the range where my LabRadar was acting up so never got a velocity reading for 63.0/63.5 (3/4" groups), so stopped there and ordered a new LabRadar, so today was bit better.

6.5 RPM, R26, BR2 Primers, once fired Factory Wby (Hornady Brass) Berger 156gr Elite Hunters, COAL 3.410"

Clean barrel 64.0grs- 3045/3029/3031

I adjusted the scope and then shot the 65.0gr group, 3061/3072/3070

I ran a string up from my load of 65.0grs of R26/BR2 Primers, New Wby brass and 156gr Berger Elite Hunters

65.0-3068
65.3-3089
65.6-3108
65.9-3126
66.2-3145-slight tight bolt lift
66.5-3148-slight tight bolt lift and light ejector marks, I stopped there.

Good info. Thanks. Just starting load development on my 6.5 RPM Accumark.
Duane

 

[10XSHOOTER]

The best 6.5 cartridge that I've played with was a 6.5 Remington Mag, Ackleyized. Held around 62 gr of H4350. velocity with a molly 142 SMK was easily 3200 fps.
Just couldn't get a good set of dies for it. Redding custom at the time was $600.00. probably would have been a barrel burner, but barrels are expendable.
Cleaned a 600 yd prone match fire forming brass with it.

 

[Will Henry]

I think the 257WM, necked up, would be a better 264 Win Mag and it's too bad Weatherby didn't make it. WH

 

[Hohn]

Yawn. It basically duplicates a classic case like 6.5PRC.

 

[Nomosendero]

Hohn, you are too logical