6.5-300wm, 6.5-300wm ai?
 

Anyone have any information on either of these wildcats? I'm having a rifle built soon, and I'm pretty sure I'm going with the ai version. Any info I can find would be much appreciated

The walls are pretty danged straight and the shoulder pretty sharp already on the 6.5/300, improving it would add nothing IMO.
built two 6.5/300's and so them for years
Cat

Not much out there for load data.

Would that not be similar to a nosler 26?

There is actually a lot for the 6.5/300, just not published by ammo manufacturers
Cat

Isn't the 26 a bigger case than the WSM?
Cat

I have the Leopard variant of the 6.5 X 300WSM. I built it on a Sako A7 and got data right from Berger. Short action and it shoots great. 140 Grain VLD at 3100fps. This is my sheep rifle.
Both of my Browning single shots and sulljr's Ruger single shot ran about the same .:)
Cat

Ya, I thought the 6.5/300 was based off the 300wm, I didn't realize it was based on the wsm case. I just figured it would be easier for a guy to have it chambered in 26 nosler, you could even buy bullets over the counter, and talk about knock down power. I haven't seen a 130gr pill knock the legs out from an animal like it.

The OP wrote it as wm, not wsm.
I think he means the 300 Win Mag necked to 6.5

In that case just buy a 264 Win Mag and be done with it
Cat

As short as the neck is on a 300 Win Mag case for holding 30 caliber bullets I cant help but think you could make a wiser choice in wildcat chamberings for holding the 6.5's.

exactly,......and like DH says, you will have a very short neck when necking the 300 Win to .264"

Why not neck the 7 Rem Mag to .264"?...:party0052:

Why not buy a nosler 26?

Why not just build a 6.5-300 wby. Weatherby is building them. That means brass will be available and quality brass at that.

Or build one of the 6.5 Sherman's or SS Sherman's they will out produce a 264 win mag hands down. I got both and there is no comparison.

I'm after the win mag case. The 264 is a necked down 7mm rem case. Which is a shortened 300wm case. One of my reasons for the 6.5-300wm is I already have an action that's ready for the belted mag case, and have a large supply of fully prepped and weight matched brass for this cal.
I've had my hands on the new weatherby 6.5 and really wasent impressed with the rifle, and not a weatherby fan by any means. 26nosler would be cool but if have to resupply with new brass. As far as the neck goes, I will be having a custom reamer built and have already taken neck length into consideration. And have left it in the hands of the man drawing up the prints for the reamer.
I'm more than expierienced with reloading and doubt I'll have any issues finding a load that works. I also like things that not everyone has and really don't follow mainstream anything.
But any insight on this cal in general is appreciated and am always receptive to different opinions and ideas

Well, that is the main reason to do a wildcat these days isn't it, to have some years by " different":sHa_shakeshout:

I have always compared wildcatting to hot rodding cars , lots of fun and you end up with something unique :
Every now and then you get someone that think they are going to change the gun world or Or think they have something revolutionary and new but in this case it's a simple matter of " got brass, got action, let's have some fun"
Have a riot with it, I'm sure it will be a very enjoyable experience !:)
as far as personal experience with this wildcat however , I gave not be , but will stay tuned D for your results !:sHa_shakeshout:
Cat

The 264 win mag came out about 3 years ahead of the 7mm rem mag and so isn't based on that case but was actually one of the win mag family that was introduced in the late 50's based on the 375 H&H case. These were referred to at the time as "short" magnums because they were a shortened H&H cases. This name never did catch on and all but died out by the time winchester came out with the WSM and WSSM line which are today also called "short" magnums.

If I was building a hot 264, I'd opt for the new 6.5 Wby as dies and reloading data is available as well as impressive performance!

The advertised results of the 6.5 Weatherby look amazing. It would be interesting to measure the distance to the lands from new and every 100 rounds.

The 6.5wby is cool. But it's still a weatherby, and that's one of the farthest things on my list of wants lol. They're overpriced for everything( rifle, brass, and loaded ammo) and soooo overrated it's not even funny lol

When my Sherman was giving me some grief I was thinking about re chambering it. If I would have had a magnum bolt face it would have been a 6.5-300. And I would do it hands down especially since you have brass and everything.
I would get a reamer built and throated to shoot the 160 grain matrix. I shot them in my Sherman they shoot very well and the best part is you can get them.
Marshall answers emails almost instantly and get stuff shipped very quick.

I was thinking that if yu were chambering I would try a 6.5-300 wby based on the action you have. The 6.5 nosler has done nothing to impress me as far as velocity.
All of my new builds I base on what is available for brass and the quality of the brass available.

The 6.5 nosler and wby both impress me with velocitys. And have had my hands on a wby at the range. So it's a bit of a friendly challenge between myself and the 6.5wby owner for velocity and accuracy. So that's another reason I'm more interested in the win case.
As far as projectiles goes, it's a toss up between the 160matrix pill and the heavy chinchaga pill(can't remember what the weight is at the moment). And I've heard good things about both bullets. So it will be cut to run either of these heavy for cal pills for sure. And back to brass, seeing as I have a very large quantity of win mag brass that is already fully prepped and weight matched, pretty sure I'm still leaning towards the win mag case.

To be honest, I don't see what the 6.5x300 Wby offers that the 270 Wby doesn't but to each his own however, don't knock the Wby's until you've had a couple!

I don't knock the weatherbys at all as far as a hunting rifle goes. I've shot and played with tonnes of them. But I have yet to see one that is up to my accuracy standards that hasent been touched by a gunsmith. The .277 cal bullets however lac the bc and sectional density that I like as well. Currently I have 4 6.5 cal rifles, so I'm already stocked up on 6.5 projectiles, and only one .277cal with only one flavour and weight of bullet to go with it.

You must have very high standards of accuracy. My experience has been that Weatherby rifles are no more or no less acurate than most other production rifles. Not all of them, but the majority of of them I've seen will shoot MOA or better out of the box.
You must also have very high standards concerning bullets. Here's the stats off of Nosler's website for Long Range Acubond bullets.

6.5mm 142 gr, SD 0.291 and BC 0.719
277 cal 150 gr, SD 0.279 and BC 0.625

The 6.5 mm bullet has better numbers alright, but not by much. Under practical hunting conditions these differences are purely academic.

What kind of velocities were they getting with the 6.5-300 wby ? Or nosler for that matter.
I have a couple of fast .257's. One is a 257 stw the other is a 257 stw ai. The ai is just not worth it in that case. They are fast but for the extra few grains of powder it's not worth it. The 6.5-300 I am sure if you did the ai version it wouldn't be worth it.
The 26 nosler doesn't impress me much with the velocity compared to powder burnt. Right now I am shooting the 6.5 sherman and a 140 at 3305 fps.

I was doing some reading the other day on a 6.5 saum. Supposedly really good barrel life if you slow it down to 3000 fps.

The SAUM is a good cartridge, yes.
I have worked with both it and the WSM I prefer the SAUM
Cat

You're right. I do have fairly high standards as far as accuracy goes. Most of my rifles are capable of 1/2noa or better, with a couple of them consistently shooting better than 1/4moa. And yes all but 2 are custom rigs. One of the factory rifles is the one I'd like to use in the 6.5-300 build, mainly because the barrel is shot out on it.
As far as bullets goes. I'm a big 6.5 fan and have been for years. This rifle will be used for both target shooting and hunting. On paper sectional density really means nothing. But the bc on the other hand, really comes into play at anything over 4-500yds. Sectional density, wile it isn't a whole bunch different between the .277 and the .264, every little bit helps. So I'll take what I can get. I've been shooting a semi custom commercial m98 in 270win for years. Love it. It's never failed to put down game. And is my go to hunting rifle every year. But I don't want a 270 cal rifle on this build. I want 6.5, and a hot 6.5, that not everyone has.
I know there's numerous other hot 6.5 cals out there both faster and slower or faster. Some better for one reason or another, availability of components, better barrel life, better efficiency. I planned on an overbore cartridge burning lots of powder, and moving fast. And with the available components that I have on the shelf. 6.5-300win mag seems like a good choice for me. And that's also wildcatting. Dream something up for a cal and case, and someone has done it already. Do some home work, and have at it. If it's what you want, do it and have fun, like a hotrod or a Harley, make what you want of it. I'm not a fan of weatherby so I just won't buy or build one. They build some classy rifles, just not my style. That's why I ask about this specific cal and case.
N

Well let us know how you get on, once loads are worked up, I be interested, I have a .264 win, and its no slouch with the newer powders, retumbo (ADI2225) or reloader 33,
Tried to sight in a load out at a mates farm, using a 125gr Partion this morning, with a very healthy dose of reloader 33, first shot on the target, in the paddock, a Fallow deer yearling stood up, from its hiding spot, 50m out, so it got a whack with a 125gr at high speed.
destructive, bloody hell, , likely less damage, if it went threw a combine,

Brettmaccoy,
I'm not trying to talk anyone into or out of anything, far be it for me to do that. I was just taking you to task for a couple of comments you've made and I think I've made my point.
I shot several the 264 Win mags for years and they killed a lot of game. I thought it was the cat's meow right up until I purchased my first crono back in the mid eighties and discovered it had very little practical advantage over the 270 Winnie and it was nowhere close to the 270 Wby. Since then despite playing with 6.5 Swede's, my interest in the 6.5's has only been luke warm until the new Nosler and 6.5-300 have made their appearances. I also think the 6.5-300 using the Win case will be more efficient than using the Wby case without sacrificing much fps.
Good luck on your build and I'm looking forward to the range reports.