help with a new caliber

[Booney]

I was thinking of these three calibers and cant decide. 6mm-284 243 Super Rockchucker, or a 6.5-284. I'm kinda leaning towards one of the 243 because i want a good varmint round but i do like the versatility of the 6.5 so i guess what my question should be what 243 round do you like better and then what round do you like best. thanks

 

[mopar440]

6.5 works for varmints but do you plan on hunting anything that would require the heavier bullet if you are just hunting varmints 6mm would fine

 

[Chas1]

How far out do you realistically plan on shooting the little buggars?

 

[McKinneyMike]

Admired the 243 Rockchucker from a far. Love the 6.5-284. Never tried the 6-284, but bet it is a killer round, as I love its brother.

These are pretty hefty loads for strictly varmints, IMO, but really depends if you are looking at really LR shooting of these critters. How big are these "varmints" that you are planning to explode? I don't think that I would want to spend the entire day blasting away at a PD town with any of them myself

 

[sniperjwt]

Go with the 243 Super Rockchucker. I have one and it is awlsome. I would go with a 1-9 twist so you can shoot the heavier bullets if you want. I have a 1-10 on mine and shoot the 90 grain Bergers at 3600fps. Can get 3700 but not as accurate in my gun. My neighbor also has one of these and has killed a groundhog out at 930 yards. I have not had the chance to really streach the legs out on mine yet with my farthest shot with it has been at 300yards. Only drawback is the price of the dies. I think they run about 140 bucks. But i think it is well worth it for this caliber its a real standout. If you got any questions about it just send me a PM.

 

[Boss Hoss]

I like the 6.5 284 because it is so accurate but speed is a consideration for the 6mm wildcats---more room for error on drift and elevation...

 

[Long Time Long Ranger]

I have the 243AI, 240 wby, 6mm-06 imp which I think is your super rock chucker and the 240 gibbs along with others. If you want performance the 240 gibbs is just awesome and will outperform the others in fps. It is just amazing for long range performance but with a lot of varmint shooting barrel wear becomes a factor. I narrow my two choices down to the gibbs and the 243 AI. The others are just in betweeners that fill the gaps and are not as fast as the gibbs but still have the barrel wear issues. So I drop down 200 fps to the 243 AI which has excellent barrel life and is one of the most accurate cartridges ever developed. When shooting varmints is there a huge difference between 3900 fps and 4100 fps when you get twice the barrel life or more out of the 3900 fps one. The 243 AI is just as inherently accurate as the 6.5-284.

With all considered if I were going to shoot it quite a bit I would build the 243 AI over any of the others because the many benefits of it outweigh the 200 fps to the gibbs. I think the 243 AI is the best overall all around 6mm cartridge. If I just wanted a high performance 6mm and that was the only criteria then I would do the 240 gibbs. Also the 264 gibbs will virtually duplicate the 264 win mag if you look at 6.5 rounds.

 

[TH]

Get the 6-284 and dont look back. Accuracy is amazing and its super flat shooting. I shoot the 107 smk at 3425fps. What ever you do dont get the 6.5X284 say in 6mm.

 

[Long Time Long Ranger]

TH, How many grains of what powder do you use to get that velocity? I have never shot the 6mm-284 and I would just like to know a comparison of how much powder it takes in the 240 gibbs vs the 6mm-284 to get the same velocity. Then I could draw a pretty good assumption on barrel life between the two.

 

[McKinneyMike]

Get the 6-284 and dont look back. Accuracy is amazing and its super flat shooting. I shoot the 107 smk at 3425fps. What ever you do dont get the 6.5X284 say in 6mm.

???On the one hand you say 6-284 is a super cartridge, but then bash the 6.5-284? What is your reasoning for this? The 6.5-284 has better BC numbers from the same case. The 6mm's are fine in their own right. I would just like to know how you came to this conclusion. I am more than a little puzzled by your comments to say the least.

 

[TH]

long ranger

I guess i should explain a little my 6-284 has a 34 inch 1-8 twist Kreiger barrel. Its built on a bat action. I shoot 52 grains of R22 at 3380 accuracy load and 3425 with 52gr of R17. Barrel life is 800 to 1000 rounds with benchrest compition accuraccy. For varmits i usually shoot to 1500 rounds. My rifle weighs 22lbs.

 

[Long Time Long Ranger]

Thanks, The 240 gibbs I have set up for the 107 smk has a 28" barrel. 59 grains of 7828 pushes the 107 3520 fps with excellent accuracy. The accuracy load in my 240 wby with the 107 is 55.5 grains of 7828 averages 3497 fps with a 27" barrel. Both shoot 1-1 1/2" groups at a quarter mile. I don't know what barrel life is because I have not worn one out yet. I would guess about where you are.

 

[TH]

Mike,

The 6.5X284 is a good round I shot it for years. But when it come to varmit hunting the 6mm's at high velocity beats it to pieces. B.C. is important but there is a fine line between the 6mm 107 sierra bc of .53 and the 142smk at .59 so there really isnt that big of a spread betwen them. The 107 at 3400fps is way way flater shooting then the 142smk at 2950 to 3000 fps. The flatter shooting rounds make up for a lot in errors in ranging calculations and wind drift. So to answer your question with my real world expirence with both calibers going ground hog hunting. I would take the 6mm every time.

Another real world expirence is bullet expansion on varmits. The 107 smk blows ground hogs to pieces. The 142 smk just punches holes in them. To each their own just my .02 cents worth

 

[Chas1]

TH, just curious. I've read discussions about barrel lengths and right or wrong I'm under the impression that at some point there's diminishing returns. 34" sounds pretty long for that cartridge...what's the thinking behind that...what am I missing?