The 284 Winchester – The only 7mm you’ll ever need?
Is the 284 Winchester (also written as 284Win) a new rifle cartridge to you? In the following article we shall explore in detail a few compelling reasons why it may just about be the ultimate 7mm largely however within the repertoire of hand loaders only…maybe its only Achilles heel…
The .284 calibre cartridges also known to the Europeans as the 7mm, benefit from an array of bullets that perform very well and have a high ballistic coefficient BC when compared to their weight and length. They tend to be remarkably slender yet stick out from their smaller rival, the 6.5mm bullets especially in weight and length.
The heaviest 6.5mm bullets approach 150 ish grains whereas the 7mm stacks that up to 195ish grain… +26% increase in weight at the top end. Cartridges for 7mm bullets vary greatly from medium sized rifle cartridges like the 7mm-08 (308win necked down) to the larger 284Win. Next step up is the popular 7 rem mag, 7 WSM and they keep getting beefier such as the 7 RUM and more recently the 28 Nosler. The latter are not in any particular order. These last two cartridges are proper high-performance hunting cartridges meant to launch 180 grain class bullets past 3200 ft/s to achieve extremely flat shooting and wind bucking qualities. Barrel life isn’t as much an issue for the latter as this will give years of hunting life even with a few sessions of training thrown in the season to ensure you can indeed shoot your 7RUM at 500yards when it matters.
While living in France and Switzerland, I had the opportunity to try the 7mm-08 (308win necked down to 7mm). The cartridge is easy to shoot and readily benefits from the higher Ballistic Coefficient of 7mm bullets. It is only limited by the number of factory rifles chambered in 7mm-08 so it is essentially a hand loader’s only cartridge, as is the 284Win. However, the volume of powder is still somewhat limited by the case capacity of its parent case, the 308Win. We know it, the 308win is what it is, an all-rounder.
So, where do we go from here while maintaining a 308win bolt face? Maintaining the same bolt face is one of the main reasons why new cartridges are constantly being invented or improved. It enables us to optimise the performance of a calibre and cartridge for a specific discipline by simply changing the barrel and using the same bolt face. A new barrel chambered and fitted is about £1000. If you have to change the action, that will quickly trickle to another £1000 for the action.
First Date with the 284 Winchester
I first became acquainted with the 284win at an F class shoot at Diggle ranges in Oldham, UK. I first shot F class right there a few years back thanks to Vince Bottomley from Target shooter magazine who got me started after reading through some of his articles and thereafter getting in touch. He’s the man!
The 284Win had already started populating the firing lines alongside magnum cartridges which require a bigger bolt face such as the 7wsm and the 7/270WSM. The 284 Winchester works very well as it readily benefits from high quality brass namely Lapua 6.5×284 cases. This means you just have to run the brass up a 7mm mandrel to open up the neck, chamfer it and you’re ready to seat bullets.
Moreover, you can build a 284 Winchester on an existing 308 bolt face (.473) which essentially means you get to keep your action reducing further expenses.
You can read an excerpt of all bolt face dimensions and corresponding cartridges below.
|Short actions with a bolt face .Dia of .384 +/-||17 Rem, 204 Ruger. 222 Remington, 223 Rem, 20 Nosler, 22 Nosler, and 24 Nosler.|
|Short actions with a bolt face .Dia of .470 +/-||225 Winchester, 22/250 Remington, 6mm Norma BR, 243 Win, 6mm Creedmoor, 250 Savage, 260 Rem, 6.5/284 Norma, 6.5 Creedmoor 7/08 Rem, 284 win, 300 Savage, 308 Win, 338 Federal, 35 Rem, and the 358 Winchester.|
|Short actions with a bolt face .Dia of .540+/-||223 WSSM, 243 WSSM, 25 WSSM, 6.5 x 300 Weatherby, 6.5 PRC, 7mm Rem saum, 7mm WSM, 300 Rem saum, 300 WSM, 325 WSM, 350 Legend and the 350 Rem Mag.|
|Long actions with a bolt face .DIA of .470 +/-||220 Swift, 6mm Rem, 240 Weatherby Mag, 257 Roberts, 25-06 Rem,
6.5×55 Swedish, 270 Win, 7×57 Mauser, 7×64 Brenneke, 280 Rem, 30/06 Springfield, 8mm Mauser, 338/06 A Square, and the 35 Whelen.
|Long actions with a bolt face .Dia of .540 +/-||257 Weatherby, 264 Win Mag, 270 Weatherby Mag, 7mm Rem Mag, 7mm Weatherby Mag, 7 STW, 7mm Rem Ultra Mag, 300 H & H, 300 Win Mag, 300 PRC, 300 Weatherby Mag, 300 RUM, 303 Brit ,8mm Rem Mag, 338 Win Mag, 340 Weatherby Mag, 338 RUM, 375 H & H, 375 Weatherby, 375 RUM, 416 Rem Mag, 458 Win Mag, and the 458 Lott.|
|Long actions with a bolt face .Dia of .585 +/-||30/378 Weatherby, 338 Lapua, 338/378 Weatherby, 378 Weatherby mag, 416 Rigby, 416 Weatherby Mag, 460 Weatherby Mag, and the 470 Nitro Express.|
284 Winchester rifle action considerations
You can run the 284win in a short action however it won’t be the best performer given that this will limit your cartridge overall length (COAL) and hence you will need to seat bullets further in, eating up the volume of powder capacity. In which case better go for a 284Win in a long action. In the handloading format we shall be exploring in this article, we shall be approaching 7 rem mag territory. How is that possible you may ask? We shall get to those points in a minute. I chose a Nesika K single shot action for my rifle build. They are well priced, smooth, cycle well and ACCESSIBLE and I could get it as a ‘package’ price from Dolphin Gun Company. They offer the same action combination for the FTR rifle builds.
Loading up a tray of competition ammunition using the UK made powder monkey, Tuned O-Haus 10-10 scales, seating bullets with a Wilson inline seater and arbor press. As good as it gets and about a minute each to load once all brass has been prepped. That takes longer especially for this neck turned brass.
Maximizing the 284 Winchester
In order to maximize the 284winchester ballistic potential, we shall:
- Pick a custom long action for this rifle build
- Increase the overall length of the loaded cartridge
- Have the barrel throated specifically for the 180 berger VLD bullet
- Seat long VLD bullets further out
- Increase the powder charge
- Use a long 30inch heavy barrel
- Drop powder in brass using a drop tube
- Tailor our load specifically to be safe and highly precise in this rifle
284 Winchester Target Bullets
I’m a huge fan of Berger bullets, yes they can be more expensive but for competition this is my number 1 choice. I want to shoot the best bullet I can afford in the rifles I had build and you only shoot 20 rounds in a string, maybe 80 in a weekend if you really push it which is not a big deal anyhow. 284Win target bullet weights vary from 168gr to 190grain which enables us to shoot this cartridge in a wide variety of ballistics. Truly versatile round in its different formats.
284 Winchester Sierra bullets
If you are a little more price sensitive, Sierra bullets offer a fantastic line up in .284. They are also proven match winners being number one choice of multiple rifle shooting record holder – David Tubb for a number of years. They offer a similar line up of .284 bullets with 6 bullets on offering ranging from 150gr to 183 grain bullets shown below as Match King or Tipped-Match King.
284 Winchester Lapua Scenar Target bullets
If you prefer our Scandinavian alternative, Lapua Scenar L offers 2 target bullets for the 284Win, 150grain and 180grain, short and sweet so as to keep it simple for you 😊
Hornady 284 Winchester Match bullets
Hornady offers 4 bullets in .284 ranging from 162grain to 190grain similar to the other offerings in terms of bullet weight. I’ve not shot any of these but there’s plenty of info out there. If you were loading in a short action, maybe the 162 grain bullets would be the ones to go for.
284 Win on Quickload
Makeshift loading bench – 1 of 2 that I setup to load my ammo. It does not have to be this elaborate, most of the time I have had to load ammo in the field or on the ranges, once you know the principles well you can get cracking.
Let’s get down to business, when I want to know the potential of a cartridge in this case the 284Win, I go to a few keystone websites to checkout what others are doing, then I contact key shooters that I know have already shot that round for sometime in competition and finally I will also thinker with the data myself on Quickload. I swear by this software. Quickload internal ballistics software is not meant to be an alternative to a good reloading manual but it surely is a game changer to identify the possibilities that one can play with ballistically, in different loading formats of the cartridge.
Vihtavouri reloading manual starts it’s loads with a bullet as light as 120grain! Let’s go to 180grain, which is the bullet we are after shooting from our Bartlein 30inch barrel 1.9 twist. Data shown below in Vihtavouri manual is from a 24inch barrel which should be about 150ft/s slower than my 30 inch barrel. Their data is based on a Cartridge overall Length COL of 74,0 mm(1 / 2.913 inch. This we shall use as a reference but ours will be longer than that – circa 3.210 almost 0.300” longer.
284 Win- Prince of open Fclass 1000yard?
My 284 Win rifle choice: Fox Barrel Block Rifle Chassis clamping down a heavy barrelled Nesika K action, 30inch bartlein barrel 1.9, resting on a Seb JoyPod Bipod – its amazing! Yes I shoot F-open on a bipod. Rifle sports a Nightforce BR 12-42×56 scope NPR2 reticle. Circa 9.3Kg
I paid a visit to Mik at Dolphin Gun Company in the UK somewhere out in the middle of nowhere near Lincolnshire sometime in end of September to discuss the rifle build. More on that rifle build in another article. He had suggested I go with a neck turn chamber .312 neck in a 30inch barrel 1.9 twist throated for a 180grain Berger which would put the Cartridge overall length at about 3.210”. This combination shoots about 2830-2890ft/s in most rifle builds. This should give a COMPETITION barrel life of 1400 rounds or thereabouts given we shall be shooting 17 and 22 round strings of fire over a 40minute competition timeframe. That’s 70 matches with one barrel, not too shabby. This means most bigger magnums are not suitable for F class, the barrel would simply get too warm and too much fouling to contend with which may also affect pressures, not to mention recoil!(no muzzle brakes allowed) To give you an example, my 300Norma Mag in its current format is a 3-5 shot rifle, then I let it cool for 10 minutes.
I had a look at the actions available and got an idea of the cost. Mik does a great package on these custom builds so if you’re looking for a no-nonsense high precision competition, tactical or hunting rifle give him a call. I’ve tried 3 rifle builders so far, no one has the turn around time of this custom gun shop – period. If all items are in stock, in 3-4 weeks your rifle will be shipped to proof house and then sent to you. He replies to his emails daily. I once asked him, how is it that you get to reply to all these international customers while keeping the shop running? He said “I’m up at 6am trash the emails first, get a few hours of work done ye, and then answer emails again.” His wife Tina replies to everything else in between. I like to give credit where its due, these guys help hundreds of international sporting shooters get sorted for all sorts of activities from Europe to Asia, Russia to Kazakhstan, South Africa to New Zealand and keeping it consistent year on year must be applauded.
Back to Quickload
Once I got back home, I plugged these numbers into Quickload for additional insights. Quickload has a function to show you different charge increments for a load, in this case we chose 0.3 grain increments. We shall load 1 round of each charge weight and while we verify the velocity that we get, we also ensure the cartridge is safe in our custom rifle. After each shot, we check the bolt lift effort required as well as other markings on the case head to check for pressure signs as we increased the charge while we use the velocity data as a guideline. Quickload tends to verge on the conservative side a little so we shall verify the data below during testing. Don’t try these loads in a thin hunting barrel, you need thick heavy barrels for this work.
Let’s take a look at the near maximum load of 57 grain of N165 assuming we work up the load and find it is suitable and safe in our rifle.
This would give us 2844ft/s at 57grain N165 with a compressed load given that filling ratio is listed as 106%. You can use a long drop tube about 8-inch-long to help powder pack in the brass a little tighter and avoiding compressed loads. Typically, when you are seating bullets with a Wilson hand die, you can easily feel the powder charge being pressed as the bullet is seated.
How far was the actual load from Quickload? Pretty darn close! 2881ft/s vs 2844ft/s predicted.
*Note on compressed loads – I recently pulled some rounds apart which I had loaded for load development of my 300Norma Magnum 1 mile rifle, they were compressed charges at 93grains of N570. When I flipped the case upside down after removing the bullet, the powder needed to be scraped a little before it started to flow back into the tub. This is to show just how tightly packed the propellant would be in these cases. Always start at the powder charge indicated by the manual and as you approach maximum charge, drop the increments by half in this case from 0.3gr to 0.1grain.
Sizing cases during load development process on the ranges using a Harrell Press at Bisley ranges. As real as it gets. Learn the basics well, practice often so you can load anywhere. IF you can load anywhere you can shoot all around the world. Thanks to all those that help me out, you’re all stars!
What’s the recoil like on the 284 Winchester?
In the format we are shooting from a heavy 30inch barrel, the recoil is barely felt. It feels like a 223rem to me. Watch the video of it going off as I invite my mate Ewen Campbell to give my rig a go.
284 Win ballistics
The ballistics for the 284 Winchester are very promising as you can see in my wind drift sheet. It shows wind drift for 10mph wind Full value (3/9 o’clock) and from 3 other different angles, the most important ones for the wind clock. It’s a sheet I always keep handy to help me figure out the wind dope for my first shot. It should get me somewhere in the 4th ring if I do it well. On proper Fclass rifle ranges, wind reading as good as 1/4MOA changes can often be made due to the sensitivity of the large wind flags as well as the wind reading capabilities of some of the top shooters over there. When you walk into an open field and try to keep 20rounds on a large piece of paper as we did in Italy while load testing for the 300 Norma Mag, our wind reading abilities were handicapped by the lack of proper indicators.
How do you work out your windage correction for the 284Win?
Rather simple if the wind is steady and the method applies to all cartridges.
- Identify range to target example 800yd (4.2MOA Wind for 10mph full value)
- Identify avg. wind speed, Example 5mph (4.2MOA/2 = 2.1MOA)
- Identify wind clock direction example. 1 o’clock (2.1 x0.5 = 1 MOA windage)
- Dial in the correction and send it
- Plot impact on data card and take note of correct windage VS estimated
Observe and repeat.
Read More about the actual build on my 284 Winchester F class rifle for 1000yard competition in the following article coming up soon. Have you got any comments? Drop me a line.