Custom round

[catwithboost]

Anyone out there shoot a 6mm-284? I have a barrel sitting here in a  Savage model 12 heavy barrel 243 and have been talking to a guy about different options and this is one he was talking about and a 6mm-270wsm. Any input out there would be great.

[JoshT]

I've had two 6/284s... neither would do anything my 6mm Rem wouldn't do. They'll out run the .243 by 100-200fps depending on the load. The 6WSM would eat barrels like a fat kid on cake... and I'd be suprised to see any significant gains over the other big 6's. If you have the barrel in .243 already... then 6/284 might be worth a spin... or .243AI... or 6mm AI... whatever, everyone loves a big 6.

[catwithboost]

So you have not had good luck with the 6mm-284 or just not real impressed with it to a normal 6mm?

[JoshT]

Both were accurate... one was a rechambered factory barrel... the other a Douglas, both at 24". It was kind of a pain necking down 6.5/284 brass... I saw a meaningless (30-50 fps) velocity advantage over my 6mm Rem... and it took 3-7 grains more powder to get it.

If I were going to build a sick 6mm... it would be a 6mm SAUM. The Remington SAUM case is a little bigger than an '06 case... and it's shorter than the .284 case. I'd spin it 1/8" and shoot the 105 Amax (3250ish)or the 115 DTacs (3100ish) in it for LR work, and 87 Vmax at about 3600-3700 for coyotes and 'chuck nuking. If you wanted to get crazy... a 70 grain NBT at about 4k would be a coyote bombing machine... but you'd be opening the throat up to the fat kid doing that.

[JackOfAllTrades]

I suppose a couple other questions need to be answered.

What is your intent for the rifle once built? What is the rate of twist of that barrel? Do intend on shooting light bullets at vermin or heavier bullets at larger game?

Answering those questions might put you in the direction of which cartrige and particular charictaristics you desire.

-Steve

[catwithboost]

It will be a target rifle and possible Antelope/Coyote. It is a 26" 1 in 9.25 twist.

[JoshT]

You might be able to shoot the 105 Amax in a 9.25" twist... but it'll be close.

Honestly... I'd leave it a .243... and spend the dough on some kick-ass brass (Lapua comes to mind) and nice glass. When it comes to tanking coyotes and pronghorn... a .243 will get it done just as well as any other other hot-rod wildcat rounds. I'd look at the 90 grain NBT, or the 95 Berger for LR pronghorn work... and the 55 grainer at 4k for coyote work. It ain't as sexy as the 6/284... but there ain't a critter on the plannet that'll be able to tell the difference, unless it's a rifle looney like me.

[littlebuf]

i reload but ive never wildcted, what is the process for necking down a case? not trying to jack the thread just sounds like you guys have a lot of experience and im always wanting to learn 

[JackOfAllTrades]

I'll second the .243 and maybe stretch that to .243 Ackley Improved. You can still shoot factory .243win and each time you do you'll be fireforming fresh brass.  +1 on the Lapua but wait till you see how she shoots with some good ole Fed or Win brass first. +1 on some Berger, but there are several other choices. I would certainly try some Hornady or some Sierra...

Littelbuf, As for necking down brass, it depends on how far you're going. Sometimes you need an intermediary step to neck down but necking down from .243 to 6mm is just a good lubed step with the 6mm die then shooting a reduced load to fireform the brass. I do the same with a 30-338. (338winmag necked down to .30cal)  It's a two step process to reduce neck size, once with the sizer die then with fireforming. Neck size once more and load again.

-Steve