.280 AI or .284 Winchester

.300winmag · Sep 5, 2013

Planning ahead for my 6.5x47 that should be finished up soon. I built this rifle primarily for target shooting, tactical matches and the occasional deer/antelope and I think it will serve me well for long range target applications. However, I would like to get another barrel for it for use on black bear, elk and bigger critters. I've narrowed it down to two chamberings, the .280 AI and the .284 winchester. Curious on what peoples thoughts are on here. I know there are a lot of .280 AI fans on here and it is rated for higher pressure than the .284 winchester, it's a great round am I am grateful Nosler got it official by SAAMI. However, I am leaning towards the .284 Winchester, this is because of the success of the .284 winchester in long range competition as well as it's little brother the 6.5x284, as well as the ease of getting high quality lapua brass. Simple run the 6.5x284 through an expander die and you've got .284 winchester brass.

THe barrel will be a minimum of 28" in length and I'm debating a brake. I don't think I'll need it for recoil but the noise does not bother me and I do like being able to spot my own shots. Any thoughts on one over the other?

Thanks!

DrMike · Sep 5, 2013

Both are great chamberings. I have a .284 in the works now; it will be a hunting rifle. The .284 is a seriously under-appreciated cartridge that is a ballistic twin to the .280. Consequently, I have two rifles chambered in .280 Remington (a Winchester Featherweight and a Remington Anniversary Model), so I haven't felt the need to own a .280 AI at this point. Nevertheless, either chambering will serve you well, putting a grin on your chin each time you touch it off.

SJB358 · Sep 5, 2013

Yeah, I would think if your running a 28" barrel, the 284 would be really impressive and easy on powder as well. Jeff (USMC89) has had one or has, and thinks really highly of it. I would think if you have the mag space, it wouldn't leave much of anything out there.. Like Mike said, it is a really sweet cartridge and coolto see some rifles chambered in it.

Guy Miner posted some great links to folks using the 284 along with RL17 and H4831.. Looked very good to me for such a small amount of powder..

usmc 89 · Sep 5, 2013

Actually you would have a 7x47 lapua not a .284 win. If your going to barrel either a .284 or a .280 ackley on a short action " asuming its short because you built a 6.5x47 on it" the term pyrrhic victory comes to mind. I would do a 7-08 ackley if I wanted a 7mm in a short action. Reason being by the time you stuff a high bc bullet "the reason for shooting a 7" you are going to reduce case capacity resulting in similar velocities to the 7-08. Single shot bolt gun disregard above statement. I built a .284 this year and have not shot a more consistant rifle to the 1350 mark. Hunting rifle where you may need a bit more energy +/- 100 fps .280 ackley, A rifle that when tuned properly and in the proper hands needs to make precision shots on animals past the 600 yard mark I will take the .284 with a 180 vld everytime. Both are great tools and will kill cleanly far past the mark the average hunter can justify taking an ethical shot.

Horsethief · Sep 5, 2013

Last thing first: get the muzzle brake. I have one on a Mauser-actioned 280 Rem. I'm pushing max loads on 150 and 160gn bullets (with GREAT accuracy) and the kick from that rifle is almost nothing. The brake I have is larger than the Weatherby Accubrake. That brake is reported to cut recoil by 40%.

As for the 280 AI or the 284 Win, you really cannot go wrong. The AI will have some higher velocities than the 284 Win, but as Melvin Forbes wrote, any .28 cal bullet hunting bullet going 2950 fps at the muzzle is going to kill nearly anything it hits if you do your job right. You can form 280 Rem brass for the 280 AI with either fireforming or the Cream of Wheat method.

Good luck, and keep us posted.

JD338 · Sep 5, 2013

Both are great rounds and the have a lot of cool factor.
The 284 Win is equal to the 280 Rem, the 280 AI is a little more.

JD338

.300winmag · Sep 6, 2013

Thanks for the feedback fella's! I'm pretty set on the .284 winchester now. I appreciate the feedback!

USMC, sorry I had a typo in my post (I've fixed it now). I meant to say run 6.5x284 brass through an expander die and you've got .284 winchester brass.

Will have to check the funds and see what I can do. But, I imagine I will have a Hart or Krieger in 7mm ordered by the years end.

Horsetheif, thanks for the tip on the MB. I'm a fan of them, I wear hearing protection everytime I go shooting, and 90% of the time I double up on it. I ill probably end up with a Defensive Edge brake on it. Being a 14.5 lb rifle with a brake, it should be as peaceful as a kitten to shoot!

HomerOz · Sep 6, 2013

G'Day Fella's,

300Win Mag, a good mate of mines son has a .280AI, which is bases on a Weatherby Lightweight MkV action, and a custom with a 24" barrel.
He is achieving velocities that are nipping right on the heals of a 7mm Rem Mag!
This is with Alliant Reloader 19, pushing 140 and 160grn bullets!!!
After seeing these chrono results, I was sold on this cartridge!
The same mate himself has a new Kimber 84L Montana in .280AI but he hasn't yet started working up loads for this rifle.
I might need to get one of these Kimber's myself!!!

Hope that helps

Doh!
Homer

sask boy · Sep 8, 2013

I tried to do do my homework before I ordered my final build & decided on the 280AI. I know Mike is very keen on the 280 Rem stating that it is very underrated. I have also read what Jim has posted on the Ackley so I decided to try one.
I hope to have it home before WT season and performing the way it should :wink:.

Blessings,
Dan