308 based wildcat?

[JustinP]

Hey guys

Need some advice:

Is there any way to improve the .308win case?

I've got a surgeon short repeater action,bionic REM700!) that uses AI mags and I'd like to rebarrel in 30cal,currently in almost shot out 6mm)

I love the 308 but was wondering if the case could be improved to give slightly better inherent accuracy,straighter body? increased shoulder angle?) but still feed through a mag and give roughly similar barrel life to the standard .308.

I'd shoot a variety of projectiles through it, from 110gr upwards to 168/175gr

Not interested in necking down to 6.5mm or 6mm.

I know it's probably weird but bear with me,and try not to laugh too loud). All suggestions welcome!

 

[jofus]

I have a 308 ackley shortened .20" and it shoots ones all day long with 135 grain chisums and V-V135.

 

[JustinP]

Jofus

Thanks for your reply. Hope you don't mind a few questions?

1. given it is shortened .20", is there anything special you have to do to the .308 brass to form it for the chamber?

2. what is the shoulder angle?

3. what sort of velocities are you getting out of the 135 grainers

4. accuracy?

5. what dies are you using?

Thanks mate

Justin

 

[jb77]

Justin by improving the 308 you are going to be burning more powder so barrel life is going to slightly shorter, but barrels are relatively cheap so go ahead, life is too short to worry about 500 or even a 1000 less shots through a barrel before it falls off.

In my opinion the average shooter never shoots a barrel out. That certainly isn't the case with the guys on this board many of them will go through a barrel in a season.

As far as inherent accuracy because of the shape of the case is certainly debateable. I do not believe certain calibers or case shapes are inherently accurate, if they were then most of the top shooters would all be using the same thing and they are not.

I believe painstakeing attention to detail in chambering and squaring an action and the outstanding barrels plus the great components available for reloading combined with the knowledge to put it all together are why we are seeing records fall constantly.

These are the good ol'days of shooting, we have never had it better!

 

[JustinP]

JB

Hear what you're saying and agree.

I may just go back to the tried and tested .308 but I am very interested to see what wildcat options are available on the case - just for the hell of it. Plus, if I lose 500-1000 rounds of barrel life over what a .308 will shoot, I'm still way out in front. Hell, I know guys who have put over 7,500 rounds through .308s and have maintained reasonable accuracy right up to that total. If I get 4-5,000, I'd be laughing and get to scratch my itch to shoot an improved caliber, which I've had for some time now...

 

[SF340Driver]

30-284 will take care of what you want. It's a short action 30-06. Have the seam plate removed from your AICS mags and you can load to 2.950" -- GA Precision does this mod for your mags.

 

[JustinP]

30-284? Now that's something I've not heard of before. Will have to do some research...

 

[mysticplayer]

An improved 308 will show way less case stretching as you ramp up pressures. The increase at SAAMI pressures is very small but if you go hotter, you will see a tangible increase with the bullets weights you are thinking about.

There is little reason you can't gain 100 to 150fps in an improved and higher pressure loading.

You don't like the 6mm or 6.5's but have you looked at the 7mm?

A 7-08AI will push equal weight bullets at similar velocities BUT the BC of these 7mm bullets is night and day better then the 308.

The 168gr 30cal bullet is a 0.475BC range of bullet. A 162gr Amax in 7mm is 0.625BC. That is an enormous improvement in reducing wind drift at longe distances.

A 30-284 is a great wildcat and mimics the 30-06. Ballistically, there is little that is gained at LR over a 308. The 7-08AI or better yet, a 284 will simply smoke the 30's.

Jerry

 

[JustinP]

Hey Jerry

It's not that I don't like the 6 and 6.5s,I've owned a couple of 6mm chambered rifles) I was just thinking of going back up to 30cal for this project so I don't have to change barrels so often and was hoping to find something I could use on the .308 parent case that would feed through my short action and mags.

I have no experience with the 7-08AI and will need to do some research. I thought about 6.5-08AI as well but doing comparisons, on ballistics, case forming, components, barrel life, etc. is proving a shade difficult when I don't know a lot about the calibers.

Thanks very much for the steer. If you have any data on the 7-08AI, I'd love to hear it.

Justin