6X284 in competition

[DOGCAPPER]

Is it worth my while to buy a 6x284 13 twist to shoot comp @ 600-800 yds..Bbl has shot .260/100..Use in Club matches not Nationals....

 

[1000yardstare]

A good friend had a 6/284 custom barrel made for Canadian F Class. After 500 rounds accuracy went south. He took it to the barrel maker who examined it with a bore scope. Don`t know how much the barrel maker was exagerating but he said the first 6 inches of rifling had "disappeared". To be fair the barrel maker had warned my friend that he could expect "short" barrel life.

 

[CJ6]

A 13 twist will keep you with the lighter bullets also 80 gr maybe 85 gr tops.

 

[Ironworker]

I don't know what brand BBL that was . Assuming it was 416R which is what my HART bbl is made of I have nearly 1,000 rnds down my tube same caliber but 10"twist. Just recently shooting 90gr Nosler BT I'm still getting 1/4 MOA at 100yds.

 

[Laurie]

DOGCAPPER,

have a look at:

http://www.targetshooter.co.uk/

current (Jan 2010) issue, pages 40-44, article titled "Wildcats I Have Known and Loved - the Fabulous Sixes" by the UK Benchrest 1,000yd small group record holder, Vince Bottomley.

(Free online magazine).

Vince has built and used at least a couple of long-range BR 'light guns' on this cartridge and says barrels just 'die' at 500 rounds, so far as BR accuracy is concerned at any rate.

This is entirely consistent with the same case and powders only providing 800-1,200 rounds in less demanding (accuracy-wise) F-Class or Fullbore Rifle roles in the 6.5-284 form where the hot gasses are going down a much larger bore area consistent with doubling the barrel life compared to a 6mm version.

6-284 is a quite unsuitable cartridge for any high round-count competition target shooting discipline, except maybe for barrel making company owners who relax with a bit of home gunsmithing too between matches.

Your 1-13" twist is also far from ideal - no, let's call a spade a spade as we say on our side of the Atlantic - is virtually useless for the ranges you're contemplating shooting over as you cannot use any match bullet heavier than 70gn or so. Running Miller's twist Rule with the 80gn Sierra BltzKing and 87gn Hornady HPBT bullets, both good 'varmint' but neither a match design at 3,500 fps in 1-13" twist barrels comes up with Stability Factor values of 1.18 and 1.04 in standard environmental conditions. The minimum recommended Sg value is 1.4, although you can usually get away with a lower figure unless shooting on a sea-level range in very cold conditions. You would have no chance to get any 90gn HPBT Match design to work in this twist.

I'm not saying you wouldn't have a lot of fun while the barrel lasted, but you'd be burning the barrel out in a very few matches while using inefficient bullets compared to even a little 6BR shooting 105s. If you're going to rebarrel anyway and want to speed the process up, great - otherwise, no!

Laurie,
York, England