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6.5-284 Cartridge Guide
Posted By admin On October 4, 2010 @ 2:28 am In Cartridge Guides | No Comments
The 6.5-284 Cartridgeby Jason Baney, Asst. Editor The versatile, ultra-accurate 6.5-284 cartridge has exploded in popularity in recent years. From 600- and 1000-yard benchrest, to the tactical and F-class shooting disciplines, this round has made its grand entrance and is here to stay. The 6.5-284, originally a wildcat version of the .284 Winchester, is now more popular than its parent. The .284 Win case was created, as a 7mm hunting round, to deliver 30-06 performance in a shorter case, but it never caught on as a competition cartridge. Today, the 6.5mm version is one of the most successful long-range match rounds ever invented. The 6.5-284 has far eclipsed its parent case–at least for the time being. (The new, high-BC 7mm bullets have inspired some shooters to revive the straight .284, using necked-up 6.5-284 brass.) There have been some amazing results with the 6.5-284 over the last couple of years. In 1000-yard benchrest, the 30-calibers are still used by more shooters, but the little 6.5 is becoming more prevalent every season, and taking home more than its share of fake wood trophies. Rich DeSimone set a tough record to beat in the IBS Light Gun category with 1.564″ 5-shot group at 1000 yards with his Ackleyized 6.5-284 Super and Clinch River 147s. Last year alone, John Hoover and his daughter Marissa each nailed perfect 100 scores at Williamsport with their 6.5-284s. In 1998, John shot Williamsport’s first-ever perfect Light Gun 100 score, with 5X and a 5.585″ group for TEN shots.
Choice of Brass6.5-284 brass is produced by Hornady, Lapua, and Norma. Lapua and Norma cases have performed far better than the Hornady brass, and Lapua is the preferred choice of most shooters. It is cheaper than Norma from most vendors, and most shooters believe it is both more consistent and more durable than Norma–giving longer brass life and performing better with hot loads. Unfortunately, both Lapua and Norma have delivered a few disappointing lots of brass over the years. But for the most part, the brass from these two companies is excellent, and will deliver superb results, particularly if you sort cases by weight. A third option is using Winchester .284 brass, necked-down to 6.5mm. There are two varieties of Winchester brass, the bulk Win brass sold currently, and an earlier version that was sold in individual 20-round boxes. John Hoover uses the early Winchester brass and he believes it is superior to anything you can buy today. He’s done extensive testing with Winchester, Lapua, and Norma brass, and his early production Winchester has always performed best in his family’s rifles.
Preferred Neck Diameter Mark King has smithed a lot of winning Williamsport rifles using a .294″ neck with a 0.291″ loaded round. Jason Baney feels this is the best set-up. “Mark likes .294, and so do I. It lets you clean up 99.9% of all the necks. Removing any more brass than that just isn’t necessary, and I think a lot of guys find the thicker necks shoot really well.” At the other end of the spectrum, gunsmith Rick Beginski has chambered a number of record-setting 6.5-284s using a .286″ reamer. This works with a 0.2843″ loaded neck diameter with about .010″ neck-wall thickness. Using this chamber, Billy Copelin set multiple NBRSA world records in recent years, including both small group and score records. If you hate neck-turning, and want to just barely skim the necks, Dave Kiff has a 0.297″ ‘Norma Match Reamer’ that has worked really well for many shooters. How about the no-turn option? For a tactical, varmint or hunting rifle, there is absolutely no reason not to go with a no-turn neck. You’d want at least a .299″ neck for a no-turn hunting rifle, and 0.300″ might be better. Barrel Choices–Take Your Pick Barrel life is a key issue for 6.5-284 shooters, because barrels can loose their accuracy edge in as little as 800 rounds, though 1000 rounds is more typical. But don’t throw away that barrel merely because the groups start opening up. Sometimes some aggressive throat polishing can restore much of the accuracy, and you can get hundreds more rounds of useful life by having the barrel set back.John Hoover reports: “I’ve had many barrels set back 1″. Nearly always they shoot as well or better than before.” Bullet Selection
Bill Shehane currently favors the 142 SMKs, sorted in .002″ bearing surface increments, because he feels they produce the most consistent results at 1000, with fewer unexplained flyers. Bill observed: “I’ve also shot the Berger 140s and the Lapua 139s. Both brands are good bullets and I’ve shot some of my smallest groups with them. But I’ve found the Sierras to be the most consistent. In our 1000-yard game, consistency is key. One tiny group won’t win a championship. A ‘four and one’ or a ‘nine and one’, with just one shot out, will ruin your whole day. For me, that happens less often with the Sierra 142s.” Primers
Using the RCBS unit, with its universal shell-holder, is fast and very convenient. There is also a similar bench-mounted unit. With either hand or bench tool, the color-coded strips make it easy to store primers or to switch between different brands while testing (you can load Fed 210s or other primer brands into APS strips using an RCBS strip-loading tool).
Brass Prep Working up a Load for Your 6.5-284 When long-range competitors first started shooting the 6.5-284, many pushed the cartridge to max velocities. However, it soon became clear that peak velocities did not produce the best match results. The general trend has been to back off loads to the 2950-3000 fps range with 142 SMKs. This seems to produce better accuracy in most guns, along with reduced throat wear. In selecting a velocity, most of our “experts” say to pick a load that delivers best accuracy with low ES and SD. What velocity that represents will depend on your gun and barrel. John Brewer runs his loads about 2950 fps, while Bill Shehane normally loads to about 3050 fps in an Ackleyized 6.5-284 case.
Barrel Wear–How to Extend Your Barrel’s Useful Life We asked Bill Shehane about setting back barrels. He told us: “I have done it both ways and really had better luck with a new barrel. But one or two occasions when I had a very good barrel I had the chamber end cut off and 1″ off the muzzle and the barrel continued for another 500 rounds before dying. Boots Obeyermyer taught me a trick about this many years ago and it worked on these two different rifles. Instead of just making the crown crisp again, Boots told me to cut it off 1″ because most barrels will fish-mouth in that last 1″ and just making the crown fresh does not do a 100% job. I have done that to all the barrels we have set back and plan to do it to my present HG barrel in 30 caliber now.” Shehane added that, if you plan to set back your barrel, don’t wait too long: “One word of advice is that if you expect a 6.5-284 to go 1500-1800 rounds don’t wait till it goes 1200-1300 to set it back. If it shoots very good set it back at 900-1000 rounds. I know its hard to mess with one that is shooting like that but I have found if you are going to do it–do it now and it will go 700-800 more. But if you wait you have wasted your chambering money! I had one 8.5″ twist Krieger that went over 2700 rounds doing this but that is the rare exception. I still like new fresh barrels that will shoot the group FAST. Some barrels I have had will shoot a group at 200 yards using “Point Blank” wind flags at 50 and 100 yards to test with but if I then turn around and try to shoot the same load say five shots in 15-20 seconds or less they just don’t want to stay together. Once I zero in on a condition I like to get my bullets on the paper as fast as I can before the let up or the push comes back. All that is out the window if the barrel will not shoot fast and some just won’t. Of coarse if the condition is mild and you can plot and take your time most all of the good barrels will shoot but the real good barrels for me shoot when you ABUSE EM and shoot very fast or take your time. A shooter only gets a barrel or two in his lifetime that will do that and he needs to be aware of it and take good care of that barrel. Or you can learn the hard way like I did and let everyone in the country shoot your only ‘Hummer Barrel’ out in two seasons. I did it about 10 years ago and have not another barrel yet today that would shoot like that one. But I am still looking.” How long can you expect a 6.5-barrel to last? Fatboy says: “Depends on the barrel steel, your firing style, your cleaning methods and your allowable accuracy. I have had them go as early as 700 rounds, and one going strong at 1200 when I pulled them. Most go about 1000 to 1200 rounds. My last one is at 1040 and still shooting cleans at 500 yards and high 180′s at 1000.” Fatboy adds: “Barrel life may depend on luck of the draw. I will say, copper build-up and glazed carbon in the throat is the death knell for these. I am no fan of JB [cleaning paste], but it may sometimes be neccessary. I’m ashamed to say it, but I use it about every 250 to 300 rounds if the rifle stops shooting the way I like it. If it shoots, the JB stays in the cleaning kit. That will generally bring back the accuracy, but makes the copper harder to clean after the scrub.” John Brewer has seen barrels go as early as 700 rounds, though generally he gets about 1000 rounds or more of good barrel life. How does one know when a barrel is “shot out?” John explains that the rate at which it fouls out will tip you off. “I won’t travel across the country to a big match with a barrel with 700 rounds–it’s too close to its end life to chance it. You see barrel end life when the group opens with nothing but fouling shots. The barrel is not worn out per se, but it fouls out MUCH more quickly. It may still shoot a tiny 10-round group but it won’t do thirty. In the matches ten accurate rounds won’t cut it.The barrel may hold accuracy for 10 shots but not 30.” John has restored accuracy to a couple barrels with very rough throats by using Cratex points (a rubberized abrasive Dremel Tool attachment shaped like a bullet). He turns the point down in diameter to fit the bore, then pushes it through with a cleaning rod. This is sort of like fire-lapping without the fire. NOTE: This is really a last resort procedure, and is done with hand pressure only–never with power. Try it only if nothing else works. Cleaning Tips 600-yard IBS Shooter of the Year Joel Kendrick believes that, with fine match barrels, carbon fouling is the real culprit: “Most people worry about copper when they should be worrying about carbon. I’ve been using a new product from Tom Meredith, a liquid he simply calls “TM”. I used this all week at the Super Shoot and it works great on carbon.” How do you find the carbon ring? Here’s what John Brewer does. He pulls a NYLON bore brush back through the bore, from muzzle towards the breech. It moves smoothly until it hits the carbon build-up where you’ll feel lots of resistance on the rod. That’s where you need to scrub with Iosso paste or JB. NOTE: we do NOT advise reversing a phosphor bronze brush through the bore. And NEVER short-stroke with a tight-fitting bronze brush! |
| 6.5-284 Long-Range Load Map |
| Powder | Grains | Primer | Bullet | Velocity | Comments |
| Hodgdon H4831SC | 51+ | F210m | Sierra 142 | 2950 fps | Jason Baney Load |
| Hodgdon H4350 | 48.5 | F210m | Sierra 142 | 2950 fps | John Brewer Schneider Barrel Load |
| Hodgdon H4350 | 49.0 | CCI BR2 | Sierra 142 | 2975+ fps | Hoover Match Load. Fire-form at 48.0. |
| Hodgdon H4831SC | 51.5 | F210m | Sierra 142 | 3050 fps | Bill Shehane Load for 6.5 Shehane (Ackley shoulder, .008″/inch taper) |
| Hodgdon H4831SC | 51.0 | F210m | Sierra 142 | 2885 fps | Froggy’s Tactical Load, 26″ bbl. |
| Hodgdon H1000 | 55.0 | RWS | Sierra 142 | 2880 fps | Hodgdon Max load (compressed). Moly SMKs. Win brand brass, necked-down. |
| Hodgdon H4350 | 49.5 | CCI BR2 | JLK 140 | 2980 fps | 28.5″ Krieger. Very consistent. |
| Vihtavuori N160 | 48.5 | F210m | Lapua 139 | 2950 fps | Moderate, prone competition load. |
| Vihtavuori N165 | 53.0 | Win LR | Lapua 139 | 2940 fps | Jumped .025″ in 30″ Krieger bbl. |
| Vihtavuori N165 | 53.0 | F210m | GTB 141 | 2950 fps | 33″ bbl. Burns clean, good barrel life. Cauterucio VLD. |
| WARNING: With all loads, ALWAYS START 10% LOW and work up incrementally. |
| Factory Reloading Data | ||||
|---|---|---|---|---|
| Accurate Arms | Alliant Powder | Hodgdon Powder | IMR Powder | Vihtavuori (.pdf file) |
WARNING: ALWAYS start 10% below these loads and work up. Seating depths have a huge effect on case pressures–moving the bullet just .010″ one way or another can push a “safe” load into the danger zone. Lot variances with powders can be extreme. Whenever you buy new powder, even the same brand, start 10% low. NEVER assume pressures will be safe if you change lots or ANY component. Case web growth is probably the most reliable indicator of over-charge. By the time you’re getting stiff bolt lift or ejector marks with fresh brass you’ve exceeded proper pressure levels. Ambient temperatures can alter pressures considerably. Don’t assume cold weather loads are safe in summer. As you approach max loads, reduce the load increments. Just 0.2 grains can make a difference.
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