Thread: . 284 Winchester

Originally Posted by Puffin

Further to my earlier post, I've since cross-checked several dimensions on the Manson and JGS regular SAAMI reamer drawings.
The neck diameter runs from 0.323" to 322". Necked up but unturned 6.5-.284 Lapua brass measured 0.3120 - 0.3126" loaded, so that is already 10 thou expansion on firing. If the brass is then turned and tidied up for a donut then 0.310 is about right. That is quite a lot of to-and-fro for each firing/resizing cycle. Online reports indicate that the Norma .284Win brass has thicker neck walls than either the Winchester or necked-up Lapua brass at 0.316" give or take. This might be reason enough to use Norma brass in a standard chamber, but also a potential safety issue if the chamber is cut with a non-standard neck.

The SAAMI profile does NOT include parallel sided freebore. It tapers down from 0.290" ahead of the neck at 47' 33" (0.7925°) in one continuous freebore/leade. At that angle is narrows to the nominal bullet diameter 0.284" at 0.217" ahead of the commencement of this profile, so this figure can be substituted roughly for freebore. It looks like many here are getting good accuracy from their .284s, but based on this I don't imagine many of those bullets that aren't 180gr are out near the lands.

Yes that all sounds about right.

My M595 was rechambered a long time ago before my ownership.

It has a .322 neck, I'm running new WW brass in that which measures .313 on a loaded round. So yeah it will be working the necks alot, very important to annual.

When I first got the rifle it came with some fired WW brass I noticed some of the necks were split or split after I fired them once or twice.

When I got my t3 rechambered I got gunworks to use their other reamer with a .317 neck and a different lead angle.

In this rifle I have used necked up 6.5-284 Lapua brass which I neck turn to remove the donut that forms after expanding. A loaded round of this measures .311

I always remember reading that the 284 win doesn't like too tighter neck clearances.

In loading for both rifles I've always found that I cannot run the powder charges that I believe I should be able to in the barrel with the .317 neck.

I don't know if it's due to the lower neck clearance or the different lead angle.

Whereas the old M595 with the big sloppy neck has always been able to run the charges that Quickload tells me I can without seeing pressure signs too soon on a ladder.

Originally Posted by GWH

...doesn't like too tighter neck clearances.

From my online searching on this 284win-specific topic (embarrassingly extensive) the anecdotal reports were for an effect on accuracy rather than early pressure signs. < 0.003" ( 1.5 thou each side) gave flyers that were absent for larger clearances.
.004"-0.006" was thought to be a good middle ground between avoiding this effect and working the brass unnecessarily hard.
So, yes, at 0.006" I think it might be something else. What were the signs in the Lapua brass in the T3 please that led you to call a halt to the load development ? Ladder? I'm not sure I follow that. What about the cases dimensionally and extraction?

Originally Posted by Puffin

From my online searching on this 284win-specific topic (embarrassingly extensive) the anecdotal reports were for an effect on accuracy rather than early pressure signs. < 0.003" ( 1.5 thou each side) gave flyers that were absent for larger clearances.
.004"-0.006" was thought to be a good middle ground between avoiding this effect and working the brass unnecessarily hard.
So, yes, at 0.006" I think it might be something else. What were the signs in the Lapua brass in the T3 please that led you to call a halt to the load development ? Ladder? I'm not sure I follow that. What about the cases dimensionally and extraction?

Heavy bolt lift and ejector marks on brass at charge levels lower than I expected the max would be.

After I neck turned a bit more things improved and I could run higher charge weights. But I still can't run it where I thought I'd be able to.

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Originally Posted by GWH

Yes that all sounds about right.

My M595 was rechambered a long time ago before my ownership.

It has a .322 neck, I'm running new WW brass in that which measures .313 on a loaded round. So yeah it will be working the necks alot, very important to annual.

When I first got the rifle it came with some fired WW brass I noticed some of the necks were split or split after I fired them once or twice.

When I got my t3 rechambered I got gunworks to use their other reamer with a .317 neck and a different lead angle.

In this rifle I have used necked up 6.5-284 Lapua brass which I neck turn to remove the donut that forms after expanding. A loaded round of this measures .311

I always remember reading that the 284 win doesn't like too tighter neck clearances.

In loading for both rifles I've always found that I cannot run the powder charges that I believe I should be able to in the barrel with the .317 neck.

I don't know if it's due to the lower neck clearance or the different lead angle.

Whereas the old M595 with the big sloppy neck has always been able to run the charges that Quickload tells me I can without seeing pressure signs too soon on a ladder.

My 284win is an ex tikka 20 inches 7mm 08 barrel with .322 neck. Work up to 53.3gn win760 powder with 162 eldx and Winchester brass, I only get 2690 fts which seems on a slow side of velocity lucky it is accurate. . @GWH If you can shine some lights on it I would much appreciate it.

Try RL17 or Superformance powder, u should get 150 fps with 160-162 gn pills

Originally Posted by chainsaw

Try RL17 or Superformance powder, u should get 150 fps with 160-162 gn pills

IMR 7828ssc also goes well in 284 with heavy for cal bullets.

I've tried all of the above in mine, got higher velocity with some but the grouping wasn't as good as my h414 load.

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Originally Posted by Rock

My 284win is an ex tikka 20 inches 7mm 08 barrel with .322 neck. Work up to 53.3gn win760 powder with 162 eldx and Winchester brass, I only get 2690 fts which seems on a slow side of velocity lucky it is accurate. . @GWH If you can shine some lights on it I would much appreciate it.

I ran mine at a very slow but very accurate 2650 fps with 162s and 2213sc. Still killed everything stone dead.

Originally Posted by Spitfire

I ran mine at a very slow but very accurate 2650 fps with 162s and 2213sc. Still killed everything stone dead.

What’s your longest kill with it? ��

Anyone tried the likes of H414 or Rel 17 with lighter projectiles like the 150 ELD-X or Berger 140 VLD for example?

Originally Posted by stagstalker

Anyone tried the likes of H414 or Rel 17 with lighter projectiles like the 150 ELD-X or Berger 140 VLD for example?

With the 150gr NBT I use to run in my 22 " 284 I only used a stiff charge of 2209, 2970 fps and shot really well.

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Originally Posted by Spitfire

I ran mine at a very slow but very accurate 2650 fps with 162s and 2213sc. Still killed everything stone dead.

so it was doing what a .280 should do all day long without any fluffing around.......

Originally Posted by Kudu

Mine is in a Remington Short action with a 19" barrel. At the moment I shoot the 150gn Nosler ballistic tips doing 2860.

Although Nick personally would not go lighter than 150gn, I would. My favourite load was using the Berger 140gn VLD with RL 17. They were going at 3040 fps and were a bloody lethal load. I only stopped using that as I could not get hold of any more RL 17.

Makes sense in a short action for sure. Damn good bullet that 140 vld. Killed a few things in the old 7mm08 with it

Originally Posted by stagstalker

Anyone tried the likes of H414 or Rel 17 with lighter projectiles like the 150 ELD-X or Berger 140 VLD for example?

Yup...3040fps using RL17 and the 140gn VLD. Thats with a 20" barrel.

I've had a .284 Win for the past few years where it was a reamed out 7mm-08 T3 by Gunworks who did a dam fine job. The barrel was cut back to 16 inches with a DPT suppressor and that rifle simply just shoots. I've always run 150 gr Sierra (#1913) with AR2209 which give me a 2 inch grouping at 300 mtrs with some necked up 6.5/284 brass.

I haven't tried any heavier projectiles as I always wanted to limit myself with this setup to 150's and I've always run AR2209 as I wanted some RE17 but that powder was just hard to obtain, perhaps supply for it now is different but I've also heard mixed reports on that powder being temperature sensitive.

With my loads I've shot heavy bodied Red stags out to 300 mtrs dropping them like a sack of the proverbial and even knocked over a Bull Thar last year out to 420 mtres but I also found the 150's were just a bit too heavy for Fallow where the projectile would pass through an animal not dumping all of that energy into the deer or expanding creating that desired bullet channel so I figured a lighter projectile for Fallow is more desireable. On Sika they were fine, certainly a large exit hole and a blood trail a blind man could follow.

When I initially tested my .284 loads I was getting 2970 fps but I later found I had a dodgy chronograph and later on when I tested with a lab radar I found my loads were going 2570 fps which I consider slow but still deadly!

I've done some other playing around with results as below all tested with a lab radar:

.284 Win, Federal Large Primer, 150 gr Sierra
53 gr RE17 = 2693 fps
54 gr RE17 = 2797 fps
55 gr RE17 = 2871 fps
56 gr RE17 = 2934 fps

53 gr AR2209 = 2570 fps
54 gr AR2209 = 2616 fps
55 gr AR2209 = 2675 fps

Accuracy was not as good as what AR2209 would give me but perhaps with some playing around with seating depth or another projectile in the 150 gr range such as a 150 gr BT the accuracy would improve?

I also considered switching down to a 140 gr projectile and looked on the net and read somewhere of an American hunter who swore by his .284 with a 140 gr partition projectiles that he hunted all of North America's game extensively with so I tried some 140 BT's which I had on hand and the results are as follows:

.284 Win, Federal Large Primer, 140 gr Ballistic Tip
54 gr RE17 = 2812 fps
55 gr RE17 = 2894 fps
56 gr RE17 = 2958 fps

Again accuracy wasn't as good as the my main load but groupings were still around the 1.3 inch from memory.

I've owned a .280 Rem (first in Sako AV action & second in a T3) before and between the two I find the .284 better as it can be run on a shorter barrel where as the .280 Rem needs that longer barrel, the .284 is also a more versatile cartridge in the Tikka actions which is what most people are running them in but that's just my opinion and experience on the two.

If I was to build another .284 I wouldn't go to a 16 inch barrel. My minimum would be 18 inches just so I could have that little bit more speed.

Powders to try have always been AR2209, next is Superformance and the best for speed is RE17

What I plan for the near future is to swap out my 16 inch barrel and putting on a longer 20 inch barrel as we now live here in the South where I'll continue to run 150 Sierras but I'm also keen on a good 140 gr load so I have been pondering the thought of a Berger 140 VLD which I might just have to try.

....at the end of the day though I love the .284, but a mate has sort of made it redundant. He has a load now (Not sure what recipe yet) that is accurate and shoots a 150gn ELD at 2900 out of a 7mm-08. With those figures I'm wondering what's the point of the .284!!....