6.5 Weatherby RPM

No I think 6.5 is a better choice because of the support with factory rifles with fast twist, tons of bullet support and the 6.5 fad( it's a fad for good reason). Even tho it's a flooded 6.5 market they did hit on some tweaks that aren't being offered like standard bolt face with mag velocities.

25 has no fast twist factory options and very small bullet selection for fast twist. If they made it a 1/10 twist like most 25 then it would just be a unbelted 257 wby with similar velocity. Not much a niche.

Now if they would have had someone like Hornady release a new line of bullets in 25 cal to fit a fast twist at the same time as they released the cartridge they could have created a market.

Looking at it from a factory/ trying to make $ and sell guns they 6.5 was a smarter choice
 
No I think 6.5 is a better choice because of the support with factory rifles with fast twist, tons of bullet support and the 6.5 fad( it's a fad for good reason). Even tho it's a flooded 6.5 market they did hit on some tweaks that aren't being offered like standard bolt face with mag velocities.

25 has no fast twist factory options and very small bullet selection for fast twist. If they made it a 1/10 twist like most 25 then it would just be a unbelted 257 wby with similar velocity. Not much a niche.

Now if they would have had someone like Hornady release a new line of bullets in 25 cal to fit a fast twist at the same time as they released the cartridge they could have created a market.

Looking at it from a factory/ trying to make $ and sell guns they 6.5 was a smarter choice
I bet someone is already building them a .33 on the RPM case, to use in a wore out .30-06 lol
 
Well the 6.5 rpm is 7% faster than a 6.5-06. So using that logic, a .33 RPM would be around 2775-2800 with a 225, and 2590-2620 with a 250.

.338 RPM - 2800 with a 225gr, 2600 with 250gr
.257 RPM - 3200 with a 120gr

Has a 82.5gr of H20 capacity. Should be quite nice.
 
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Well the 6.5 rpm is 7% faster than a 6.5-06. So using that logic, a .33 RPM would be around 2775-2800 with a 225, and 2590-2620 with a 250.

.338 RPM - 2800 with a 225gr, 2600 with 250gr
.257 RPM - 3200 with a 120gr

Has a 82.5gr of H20 capacity. Should be quite nice.
as the cartridge becomes less "overbore" we would expect better return on powder burn. So if 264=7%
277~ 8%
284~9%
30, 8mm, 33~ 10%?

I'm going to get one in 6.5 and likely wildcat one in 7mm. Ptg already lists the 7mm-6.5 rpm for 180s. I'm more interested in launching a 143 hammer. For a dedicated california (less free) big game rifle.
 
as the cartridge becomes less "overbore" we would expect better return on powder burn. So if 264=7%
277~ 8%
284~9%
30, 8mm, 33~ 10%?

I'm going to get one in 6.5 and likely wildcat one in 7mm. Ptg already lists the 7mm-6.5 rpm for 180s. I'm more interested in launching a 143 hammer. For a dedicated california (less free) big game rifle.
I can't wait to see if I'm close on my estimates. You would need a 1 in 8 on a .284 to shoot that 190 Atip wouldnt you?
 
I believe the reason weatherby made this round was for use of their 6 lug action. Their magnum rounds all require the 9 lug action which adds a bit of weight. I have the 6.5-300 which is a screamer and very accurate. I would not want to lug that on a mountain side. With the 6.5 rpm you can get a light weight 6 lug action in a 6.5 cartridge that outruns most all 6.5s less the 6.5-300 and some wildcats. Although the bolt face can use standard 30-06 this cartridge is rebated, so the case itself is huge.
 
I really like the case. Case capacity is just about right. Opens lots of doors to what can be done in a standard bolt face long action. I see lots of wild cats being based off of this case. PTG has reamers advertised but seems very pricey for them.
 
Necked to 7mm in an 8.5 twist and a good dose of RL26.....
That's right, Weatherby is always overbore anyways. I thought about this specific case being lengthened years ago, as Winchester made strong brass. I wish someone had a dimensional print, as I would study how it would do with the 7mm Berger 180 gr. Hybrid or 151 Warner Solids, as they are basically the same length. It is not a good case for a 257 or 6.5, if you want that go to a 6.5/06 or 257 Roberts AI, or high performance in a 25 SST or 6.5 SST Sherman Shortmag Tactical. You do know there are functionally illiterate people out there that are still buying the 7mm RUM because they are economically illiterate, also. No offense to anyone, just do the math !
 
I believe the reason weatherby made this round was for use of their 6 lug action. Their magnum rounds all require the 9 lug action which adds a bit of weight. I have the 6.5-300 which is a screamer and very accurate. I would not want to lug that on a mountain side. With the 6.5 rpm you can get a light weight 6 lug action in a 6.5 cartridge that outruns most all 6.5s less the 6.5-300 and some wildcats. Although the bolt face can use standard 30-06 this cartridge is rebated, so the case itself is huge.
.515" is not huge, .640 is HUGE. LOL
 
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