Larger 7's for F-Class

[Rogmay]

If the recoil was taken out of the equation, would there be a benefit to shooting some larger 7 MM calibers for Fclass. Take the 28 Nosler for instance, I hear about guys building 1/4" moa guns and if you could push the 195 to almost 3100 ft./s and have less time of flight, therefore having less wind drift at 1000yrds on windy days, meaning less margin of error! I would think the drift between the 28 and the 284 would be quite a bit! Been wondering what the recoil of a 22lbs 28 would be like! Is it a comfort factor with recoil that makes a lot of us shoot better! Obviously a lot of you guys have done this a lot longer than I, but I'm always trying to think outside the box, bad habit I guess! As always, your thoughts are greatly appreciated!

 

[JohnKielly]

For most, it comes down to numbers - the number of shots downrange before the barrel is toast. More powder might give you a yard or two, but the trade off in accurate barrel life could well be unacceptable & not be compensated for by the marginal extra wind bucking capability.

 

[Rust]

There is a balancing act between the ballistics a given chambering is capable of and the usability of that chambering. Something like the 28 Nosler, or 7mm RUM offer superior ballistics simply due to high velocity, but present difficulties in recoil management, heating of the barrel over a 20+ round string, barrel wear (500 rounds useful life?).

So its a matter of picking the most suitable compromise. Personally I like a 6.5 X 284 even though a barrel might make 1,200 rounds at best. Others have switched to the straight .284 or variants there of for better barrel life and better ballistics at the expense of a little more recoil. A few are running the short magnums with better ballistics but less barrel life and even greater recoil. Pick your poison.

 

[dsbw]

I agree, it's all about the best compromise, keeping in mind that there are no "free lunches" in F-open. The bigger you go with case capacity, the less effective the solution, recoil management, barrel life, general running cost being the most important issues. Even with the introduction of .30 caliber short magnums it seems as though the best compromise is to be found somewhere between the 6.5x284 and the straight or slightly improved .284 Win. After all, speed is fine, accuracy is final, with the bigger cases you compromise accuracy (recoil) for ballistic advantage.

 

[Ringostar]

but I'm always trying to think outside the box, bad habit I guess! As always, your thoughts are greatly appreciated!

If your wallet is much larger than the box, go for it. As others mentioned, barrel life would be worse than terrible. Is it worth the custom reamer, brass, extra powder used and the flinch that you'll develop just to have the barrel toast after 350 rounds?

 

[gilmillan1]

Just forget about it. Every one seeks that super cartridge that will only require you to aim at the X. In the end, a 284 always comes ahead of those ballistically superior cartridges.

 

[dsbw]

With respect, the Nosler range of cartridges is by no means "out of the box" thinking, it's simply using the "magnumising" principle. Out of the box would be to use the smallest quantity of propellant to achieve the best possible ballistic advantage, by doing so enhancing accuracy potential, and increasing barrel life. The designers of the BR cartridge, .308 Win cartridge in my opinion came closer to being revolutionary with their thinking. The real progress over the last 20+ years in long range shooting came from improved propellants, major steps forward in bullet design and also optics to actually enable accurate shooting over distance, and better understanding of ballistics. Also, rifles in general and customs specific became just better, barrels improved remarkably, and the number of good gunsmiths increased. My point is that simply adding a bigger case to the mix is counter intuitive, bearing in mind where the real advances have been made.

Just my opinion, not criticizing a view or opinion, just sharing mine.

 

[Alex Wheeler]

The 28 Nosler no doubt would be capable. In a 30" barrel you could hit 3300 fps with a 195. And from my experience the accuracy would be adequate for f-class. I doubt you would like the recoil and barrel life.

 

[ShootDots]

I know a few people shooting F-Open who went to the .300WSM. GREAT cartridge as far as accuracy is concerned AND more than reasonable barrel life. However, C-O-N-T-R-O-L of the rifle became one of the limiting factors. The other is recoil fatigue. Those individuals that were shooting the .300WSM have abandoned that route. I would imagine that a .28 Nosler or a 7mm R.U.M. would be punishing enough that recoil "management / fatigue", over long shot strings, would become untenable! Eventually, it seems almost everyone has "returned" to the .284 or it's improved derivatives. Barrel life, recoil management etc..etc.. prods most away from the LARGE BOOMERS! However, I think the 7 S.A.U.M. may just be the ticket to F-Open Valhalla! The recoil is not REALLY anymore noticeable than the .284 with 180-195's. With HIGH B.C. 7mm bullets, especially the 183SMK's and the Berger 195, should make the greatest compromise of speed, B.C. and controllability, and with today's SLOW powders, barrel life! I think that for F-Open, this may be the realistic limit.

 

[Alex Wheeler]

I honestly feel that the 280ai is a better choice than the 284. I think accuracy would be equal, brass would last longer, barrels would last longer, and you could run the 2850 node at lower pressure.

 

[Rogmay]

Lets not forget the 197gr Sierra!

I honestly feel that the 280ai is a better choice than the 284. I think accuracy would be equal, brass would last longer, barrels would last longer, and you could run the 2850 node at lower pressure.

Alex, were you thinking you could hit 2850 with the 195gr in a 280ai? or 2850 with the 183gr! I also see Sierra has a new 197gr MK with impressive BC's for the 7's!

 

[DocDoc]

Lets not forget the 197gr Sierra!

Alex, were you thinking you could hit 2850 with the 195gr in a 280ai? or 2850 with the 183gr! I also see Sierra has a new 197gr MK with impressive BC's for the 7's!

The .280 AI and 7mm SAUM have very similar case capacities. The Nosler loading data give similar velocities with the same weight bullets.

 

[Alex Wheeler]

Lets not forget the 197gr Sierra!

Alex, were you thinking you could hit 2850 with the 195gr in a 280ai? or 2850 with the 183gr! I also see Sierra has a new 197gr MK with impressive BC's for the 7's!

You could hit 2850 with the 195, barely. I was taking about running the normal 2850 node with 180s though.

 

[Rogmay]

You could hit 2850 with the 195, barely. I was taking about running the normal 2850 node with 180s though.

Alex, not to hijack my own thread, but I just finished putting together a 284, have plenty of H4350 & H4831sc along with Berger 180hybrid and VLD's and a box of 183 MK, hoping to get an accurate node over the 2800fps mark through a 30" krieger. New to the F-class and looking forward to making the Missoula shoot this year!

 

[Alex Wheeler]

Cool, come out and shoot it in some br matches with us at Missoula. We shoot every month and theres a lot of knowledgeable guys there. The 284 is THE one to beat still. If your shooting a 284 with 180 hybrids and not winning it most definitely is not your choice of cartridge. Hope to see you out there.

 

[dsbw]

.284 Win is a better solution than .280 Ackley. Short, fat case design beneficial for accuracy, case capacity of the two cases very similar, would not be much of a gain with the .280, Lapua .284 primer pockets indestructable. 284 Shehane seems to be a very good solution, but straight .284 very good.

 

[ShootDots]

.284 Win is a better solution than .280 Ackley. Short, fat case design beneficial for accuracy, case capacity of the two cases very similar, would not be much of a gain with the .280, Lapua .284 primer pockets indestructable. 284 Shehane seems to be a very good solution, but straight .284 very good.

It has been my experience that the weakest link in 6.5 x 284 brass (what is used to make .284 brass) is the primer pocket. As a matter of fact Shiraz Bilolia, owner of "Bullets.com", spent lots of his $$$s to have Norma create "straight" .284 brass with the heads "double stamped" to help with the problem that .284 brass has with easily loosened up primer pockets. They surely are easily destructable.

 

[Mulligan]

Cool, come out and shoot it in some br matches with us at Missoula. We shoot every month and theres a lot of knowledgeable guys there. The 284 is THE one to beat still. If your shooting a 284 with 180 hybrids and not winning it most definitely is not your choice of cartridge. Hope to see you out there.

Alex, where can I find the schedule for your F-class shoots in Missoula?
I checked the website and sent an email??
CW

 

[Alex Wheeler]

Alex, where can I find the schedule for your F-class shoots in Missoula?
I checked the website and sent an email??
CW

http://www.hellgatecsa.org/id5.html

 

[dsbw]

It has been my experience that the weakest link in 6.5 x 284 brass (what is used to make .284 brass) is the primer pocket. As a matter of fact Shiraz Bilolia, owner of "Bullets.com", spent lots of his $$$s to have Norma create "straight" .284 brass with the heads "double stamped" to help with the problem that .284 brass has with easily loosened up primer pockets. They surely are easily destructable.

Never had a problem with the pockets, ever. Sold my last .284 with brass on their 10th reload.