I am deliberating on a new 6mm chamber. I have a good Howa 1500 short action and am leaning towards the 6mm/284. One of my good friends shoots the 6mm/06 and I am impressed with it's performance.
That said, I'm not as terribly concerned with eeking out max velocity as I am accuracy. From what I have reviewed, the 6mm/284 turns in some exceptional accuracy when dialed in with a great stock and barrel along with ammo.
I would be looking at perhaps a 26 inch, No. 4 (1.25" dia) barrel. This outfit would be strictly used for positioned coyote and pronghorn antelope hunting at long range. The whole rig would be somewhere around 9.5 lbs.
Am I wasting a lot of effort when I could have the same setup in a 243 Win? What am I really gaining with the wildcat (its cool to be different), but at what expense and trouble vs. performance. I do reload and have plenty of data, so thats not a problem.
Any input would be valued from anyone that has crossed this bridge.
Your rifle will probably weigh around 10.5 lbs and if you have a good gunsmith put it together then get a .243 the brass is cheaper and easy to get and so are the dies. The .243 will shoot any range or weigh bullet you want depending on the twist you get. Had a 6/284 and liked it and have had a number of .243s. Have a 700 SA in a varmint rifle now and it does a great job. Good Luck
6mm-284 is an excellent long-range varmimnt cartridge. There are still a lot of people using them for 1000yd BR. I think the new World Record may have been shot with one. I know it was with a 6mm but not sure which one. You don't have to push the cartridge to the max. I would rather have a cartridge that is cruising at x# fps than one that is going max at x# fps. More versatility.
The reason most people go with the 6-284 is for velocity. If you want accuracy over velocity, go with the standard .243. 6-284's are overbored and wear out barrels faster than the .243. A custom built .243 w/.272 neck 26" barrel built by a GOOD gunsmith. Thats the way I would go.
I have had a 243 and own a 6mm/284. Dies are twice as high. Brass is work, neck to 25, neck to 6mm and trim, fire form, resize and trim. Necks should be turned after this. But after this the fun starts, especially if you have a chonograph and a lot of coyotes. Mr. Lewis said it a couple of posts above, a 6mm/284 idling is faster than a 243 loaded full chola. 70 gr BT loaded mild are 3650 in a 24 in. barrel, just the ticket for Wiley P. Coyote and 95 gr Partitions at 3400 for White Tails(not mild).
The 243 and 6mm Remington will get the job done, but if you want a real race horse in 6mm, use a 284 case.
I have investigated the WSSM clan. The thing that turns me off is the propritary action length. It is a strict 2.75" magazine length. This would only accomodate these specialty cartridges and chambers.
I like to be able to have options with standard actions (long, short, magnum and full magnum) which I believe are more resourceful at this time.
About the 6mm/284 and its like, the 284 Winchester is an outstanding chamber, being as fast as both 270 Win and 280 Rem with typically better accuracy. The case has been used to plant several 6mm and .257 bullets in. Some say the 25/284 may be the holy grail of balancing speed and accuracy.
I think the 284 Win brass feeds fine. It certainly fits the SA profile better with 6mm, .257 and up to mid weight 7mm. Heavy sevens take you into seating problems.
Sounds like you havejust about talked yourself into a 6mm/284. There are some downsides you should be aware of, they are full blown wildcats and only popular with a small cult of speed lovers. So if you build it most likely you will never be able to sell it. Where as you can peddle a 243 or 6mm Rem. Also once you cut a 284 chamber, there is not anything else you can do with that barrel. But if you coyote and antelope hunt on a regular basis, you will not want to sell it.
I would jump up a bit to the 6.5x.284. Good match bullets, available factory brass, dies are affordable, what's not to like. I would think a 107gr SierraMK @ 3300fps is coyote med. This is my next pet project on a M700SA.
Posts: 7752 | Location: kalif.,usa | Registered: 08 March 2001
I am working and will not be back home until the 24th. But I will caliper a round that night and PM you. The rifle I have is built on a long action and the barrel throated for 95 gr VLD's. So COL is not a problem, but I am 95% sure the 70 gr load with the bullet seat to base of the neck is less than 3.0 in. The reason I say that is I had a friend rechamber a Short Action 700 and if memory is correct, the 70 gr BT's seated to the base of the neck fit and fed from his magazine.
If you can wait a couple weeks, I will have exact measurements.
I had one built using Remington heavy barrel 243 for the starting point; if I had known about the 243 AI, I would have been tempted to try that instead. As is, the 6mm-284 shoots reliable half-inch groups and is my main antelope gun.
Tom
Posts: 14749 | Location: Moreno Valley CA USA | Registered: 20 November 2000
