Looking for something really specific.

[r3dn3ck]

I've been looking at 6.5mm wildcats. I'm trying to find something that uses the same case head as a .308/.30-06 and can duplicate or come very close to duplicating the performance of a .264 win mag, ie. 130gr @ 3000fps , 100gr at 3300fps. A little more velocity is ok but not needed. A little less is not desired. I'd like to stay at or just a toke above 3K FPS until I break into 140gr bullets.

Effectively, I want the juice but not the belted case. This will be for a custom rifle and I need to try and stay under 3.5" C-OAL.

Any hints on existing wildcat calibers (something there's dies for already) or something factory produced currently would be appreciated. I've scanned wikipedia for all the calibers they list and scoured the internet with some interesting results but nothing really helpful yet.

 

[highorder]

Have you considered the 6.5-284?

http://www.6mmbr.com/sixfive284.html

 

[R.W.Dale]

sounds to me like you just described the 6.5x284 lapua

 

[r3dn3ck]

Yep. It's (6.5x284)on the top of the list and appears to be the only real current answer to my question. I don't have a lot of data on it yet but it seems really popular in the long range scene. I really like the case length and it seems perfect for what I'm shooting for but I'm curious to see if there's anything else I should be considering. I'll only get 1 chance to do this right.

 

[atblis]

6.5-06 with a longish barrel.

Might want to consider some 7mms too.
280 AI
or one of the short mags
7mm RSAUM-->Hows a 180gr at 3000fps sound?

 

[Jim Watson]

6.5 - 06
6.5 - 06 AI
6.5 Gibbs

Unless for a target rifle, I'd make it a .256 Newton even if it wouldn't do 3000 fps.

 

[r3dn3ck]

All the ought-6 case based versions are pushed down the list by being in a long (well, standard) action. So, I've decided that the first thing was in fact the best thing. 6.5-284 it is. It'll fit in a short action which is important to me.

So, now comes the rest of the gun design. Right now I've got the list below as my basis, anyone should feel free to note any optimizations that would make the project more successful.

Lilja 31" 6.5-8" stainless barrel (for 28" of actual barrel length after chamber cut and fitting)
Mauser 24/47 action
Timney featherweight Deluxe trigger
Custom birdseye maple stock (I have a stock maker in mind).

Scope is up in the air. A lot changed there since I stopped paying attention. I'd like something with a tactical bent to it... so ideally mil-dot and a bullet-drop compensator turret and in adjustable 4-16 power or somewhere thereabouts. I may end up pulling one of my more pedestrian 4-16 mil-dot scopes. I could do a fixed 6 power or 10power scope but those are really going to limit the use cases.

Guys, thanks for the help so far. We've answered the primary question. Now it's just down to the niggly bits and ordering.

This will be the center gun in a 3 gun set. I'll be putting together a .22-250 and a .350 rem mag to match over the next couple years. The first gun I'm hoping to have done by fall.

 

[NCsmitty]

Many of the wildcat rounds mentioned are great, but I find that using standardized brass like the 6.5x284 does make loading a bit easier. Years ago, I wouldn't think twice about using and loading a wildcat, but the fact is that most commercial calibers will take care of business just fine.
The 24/47 Mauser is an intermediate length action and will fit the 6.5x284 well with the bullets seated out where they should be. You may have to tinker with the feed rails a bit with the fatter case, but maybe not.

I chose the 6.5x55 loaded to it's potential, in my M98 Mauser.

Your list of rifle components should allow you to wind up with a fine long range rig. I recommend using Lapua brass for consistency.



NCsmitty

 

[Offfhand]

The best performing long range (1000yards) round I've used or seen used in recent times is the 6.5 Leopard. Based on the .270 WSM case it has more capacity than the .284 case and only slightly less than the .264 Win Mag, yet fits in a short action. Shooters who use it are doing exceptionally well at 1000 yd matches because it can be loaded to higher velocities than the 6.5/284 with same bullets, meaning less wind drift. Easy to form from .270 WSM brass with single neck sizing step. Downside is larger rim dia. meaning a different bolt face. Short actions with correct bolt face are easily available, or '06 size bolts can be opened up. It is listed in QuickLoad, making it easy to make load/velocity and "what if" comparisons. But even so I wouldn't recommend it for novice handloaders. Another hot 6.5 wildcat I've had good luck with is .264 CHeetah, based on .308 case. Attaching photo of .264 CHeetah and 6.5 Leopard with .264 Win Mag for comparison.

 

[Muttt]

Nevermind

 

[USSR]

All the ought-6 case based versions are pushed down the list by being in a long (well, standard) action. So, I've decided that the first thing was in fact the best thing. 6.5-284 it is. It'll fit in a short action which is important to me.

Uh, slight problem here pardner. While the .284 cartridge that the 6.5-.284 is based on was a short action cartridge, the 6.5-.284 as loaded for LR shooting with those LOOOONG 140gr bullets, requires a long action if you want to use it as anything other than a single shot. They will not fit a short action magazine, and if you try to extract an unfired round from the chamber, you need to remove your bolt because the cartridge OAL is longer than the receiver opening. Something to think about.

Don

 

[r3dn3ck]

USSR, thanks for that. Good info.

For hunting purposes I'll be using slightly lighter bullets in the 120gr range. 140's will be mostly for playtime against paper and steel targets. I planned the 8" twist barrel so I can handle the 140's. I'm hoping I'm not going to see random accuracy problems from over-spinning the lighter bullets. I don't think it should matter with 120gr though and I can load those into the mag.

 

[atblis]

Is the 24/47 a short action? I get that it is somewhere in between short and long.

 

[~z]

To echo Don's statement, If you are gonna build a 6.5/284 build it on a long action!
~z

 

[Kernel]

I need to try and stay under 3.5" C-OAL.

That IS a long action (but not a magnum action). A short action would be around 2.800".

A .264 Win Mag case holds 82 grains of water. A 6.5-06/284 will hold about 67 gr, so they will never be able to duplicate the proformance of a .264 Win Mag. A WSM case holds +/- 81, but requries a larger bolt face. The 6.5 Rem Mag is also a 67 grain case, it's not a wildcat, but brass isn't exactly easy to find.

 

[r3dn3ck]

well, it's going on a M48. I've got a set of 3 M48 actions coming already. I will be changing some of the details after doing a little more research though. The 350 rem mag will now be either a 375-284. The 350 needs a magnum bolt face and is just problems. The .376 Steyr is now out because I'm pretty sure it's too long. I really need to sort out my 35-37cal issue. Thankfully it's the last gun of the set I plan to build.

I looked at the .22-284 as a replacement for the .22-250 but I don't need 4000fps with mid-weight bullets and I like that I can find 22-250's at the gun store in retail boxes and brass is easy to come by. .375-284 is easy to form from 284 brass.

I don't want a long action, I want a standard length action. The long action was an option but not a desired one. Anything in a magnum was right out though so I specified < 3.5" to obviate anyone suggesting one of the fine loads from weatherby or lazzeroni or other silly things.

Don's suggestions are not falling on deaf ears but did serve to confirm my notions. I don't plan on using 140gr bullets almost ever. Mostly it'll be 120's which I should be able to get into the mag, if there were to be a mag. At this point I still have the option of making the 6.5 gun a single shot. Given the 1000rd barrel life, that's probably a good thing and so I'm anticipating that as a likelihood. I still don't want a long action bolt throw. I want a standard action throw so they're definitely going in the M48's.

keep em coming guys.