6mmAI vs 6-284 opinions?

[Hammack]

I'm in the process of building a 6mm Wildcat, and have narrowed my choices between the 6mmAI,40 degree) or the 6-284. I have a new 1 in 10 twist barrel, which may not be optimum, but I have it on hand. It is chambered for a 243, but It should rechamber to either of those easy enough. I have a long and short 700 action that could be used. I do already have two 6mm Remingtons, and that kind of sways me towards the Ackley, but I also like the 6-284. Any opinions on the two? I'm assuming the long action would be the better choice. Does either one have a jump on the other? They pretty much seem to be equal.

 

[AndyW]

Hammock,

I went through the same process last year and decided on the 6mmAI. I built it on a SA repeater that I had milled out for the wyatts box. I built it to shoot the 87 grain Vmax and I can touch tha lands and it feeds fine from the SA. Doing it all over again I it is a toss of the coin. Maybe 50 fps more out of the 6-284 but no fire forming and Lapua brass. Unless you want to shoot the long VLD's a short action should work for both. With the 10 twist the 115 Berger probably won't work anyhow.
I think worrying about which will burn a barrel is a moot point with either case. I would think the 6-284 would toast a barrel faster with burning more powder. I built mine for hunting coyotes.

I get 3580 fps out of a 26"- 10 twist with the 87 Vmax. .5 MOA out to 600 yards.

 

[6BR]

If you want the fastest 6mm without having to fire form, I would go with the 6x284 for the following reasons;

1. It's faster than the 6mm AI and you don't have to form brass.
2. All you have to do is neck down 6.5x284 Lapua brass to 6mm.
3. Better Brass,Lapua)


I have owned a custom 6x284 and it was an awesome cartridge. I shot 105grn Lapua Scenars at 3450fps. It was a laser. The bad thing about these two cartridges is that they are both barrel burners. However, the 6x284 is the better of the two IMO. You can use, I think it's 7X57, Lapua brass for the 6mm AI, but you have to go through a bunch of steps to prep the brass. It's not worth it. The 6x284 is the easier choice in my opinion. Good luck.

 

[CJ6]

If your going to do either Cart.get long hvy. barrel 28-30 in.,30 is better) will get you up into 3700-3800+ fps easy.Get a straight,no taper) blank so you can set it back a couple times,throat erosion).Use slow powders H-1000,vv 170,H-870,VV 165,RL 25, RL 22 all work well. Don't run-n-gun will also help the throat issue alot. I have 3 6-284s all 12 twists the most used has just over 4400 rds. thru it with 3 setbacks and re crowns it's at 26.5 inches. It will come off be cut and re chambered to 6-250 for a pistol at about 5000 rds.

 

[Hammack]

Thanks for the input guys. I live on the farm here in southwest Georgia, and this is mainly going to be my truck gun. I'll keep it in the truck for when I run across varmints such as hogs, coyotes, and occaisionally a deer or two during season so it won't get tons of shots thru, and no long firing sessions. I just wanted something different, and I had a 6mm barrel available from another project. I own a welding and machine shop for a living, and do all of my own barrel work, so about my only expense is gonna be the reamer as I already have most of the components. I have reloaded for years, but never fire-formed brass before, but from what I had read it wasn't much to it. The main reason I had considered the ackley was because I already have an abundent supply of brass since I already own other 6mmRems, but the ability to just buy brass and size it is something I have not thought of.

 

[palma]

1. It's faster than the 6mm AI and you don't have to form brass.
2. All you have to do is neck down 6.5x284 Lapua brass to 6mm.
3. Better Brass,Lapua)

I'd much rather fire form than neck down and turn, which is a must unless you like doughnuts.

 

[CJ6]

Hammack,If your going to use it for a,Truck Gun)you will not want a 30" barrel especially a Hvy one.For that type of use you would be better off with a 243 or 6-250 etc.Alot lighter shorter easier to handle rifle maybe a Mdl 7 with a 20" barrel.

 

[1000yardstare]

Hammack: I am waiting for a 6mm AI barrel from McLennon, a Canadian barrelsmith, stainless, 1-in-8 twist, 30 inches, F Class weight. Going to use it for F,O) Class on the army ranges up here north of the border. Took some firsts in Factory Class at the Ontario Provincials last summer with a .243 Savage 12FV. Used the Sierra 107 MKing, a dynamite bullet. Struggled in the wind at the Nationals in Ottawa with the .243 so decided to boost velocity with the 6mm AI. Hope to have the new barrel in April on a 722 action. Will be single loading so the stiffer short action is not a problem. Plan to fireform at F Class practises loading with RX22 or RX25.

I have no personal experience with the 6mm-284 but one of my F Class buddies had one made up. He said that after 500 shots the first 12 inches of the rifling was gone. Don`t know how much he was exagerating but that is what he told me.