284 versus 6SLR (243AI) comparative ballistics F-class options

shockman said:
I would not go to a 130 or 123 as they have lower BC's !! All the examples you give above show that the higher BC bullets win out! I just want to have someone explain to me how a heavier bullet performs BETTER than its BC??? I see we have "one mans opinion" on how the 308/223 battle goes, and it makes sense to me? Good article! I still have some old-timers around me that think the big 30 cal bullets will trump the 7mm 180! I say if you run the velocities and BC's the math will tell, however you need a heavier than 210gr (bergers) to beat the 7mm 180, SO now what case do you need to equal its velocity??? Now I can see a whole nother set of problems with that much recoil :>))) I doubt very much that you will see those bullets knock the 7mm off it's pedestal
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That is exactly the 223 vs 308 argument. Been there, burnt out the barrels. At mid range (600m), the 223 does very well against the 308 in ALL disciplines that limit to either 223 or 308. A bunch of US top FTR shooters use the 223 for mid range then switch to 308 for LR. US High power/service rifle is the land of the 223. TR shooters also do very well as we see locally. Some have done very well even at LR as shown by some great scores in Connaught this year.

I have done very well out to 600m but pretty lousy at 1000yds.

On paper, the BC's are similar, the drifts are similar, in fact, you can make the 223 look better. So this is prime example of how paper BC does not translate into LR scores. It is highly unlikely that a load that wins at 600yds is no longer competitive at 1000yds unless something is directly affecting the flight path.

For Open, there is now a rapidly looming wall of diminishing returns. Saw several excellent shooters drive 230gr 30cal boomers to excellent scores in Raton. Their most common comment.... hard to drive due to recoil. Can tech resolve this? Of course but that is outside the box development. If tech does exist AND ranges that will allow this tech to continue, the 30's can dominate.

For most LR ranges in Canada tied to the military, this tech simply isn't going to happen or needed. Going into the Worlds 2017, where we are, is the cap for Open. A well tuned 284 or shehane is all that you will ever need. maybe a slighter larger case if you don't want to press pressures. maybe a small magnum in 30cal cause that is your preference.

Connaught effectively caps tech in F class for those gearing up for the Worlds today.

FTR on the other hand is a whole 'other world of "joy".

As to the concerns listed in that article, all easily resolved. We should be using precise scales and testing our components. With all the loading methods at our disposal, the 223 can shoot every bit as well as other notable chamberings like the 6BR as far as accuracy goes.

Is it more work? Surprisingly no. I am sure you know to what lengths some shooters will load to. IF there is less "OCD" tendency, the larger case will tolerate being a bit more sloppy but nothing allows you to just slop ammo together and expect to be competitive.

I had a distinct pleasure of scoring for an OPen shooter that got it ALL right. How about 8 shots in a row covering LESS THEN 4" at 1000yds? It as not a calm relay. Dropped only 1 point out the bottom which was unfortunate but the group was trending that way and one just squirted out. Remove that and he or she was working 14rds UNDER 8". Sorry, couldn't tell if 7mm or 30cal from the paper holes but sure impressed a bunch of other scorers nearby.

Look at the opening scores of the Worlds individual. If you shot relay 1 or 2 and dropped any points, you were at the bottom of that relay. Shooters were keeping 10 to 13 shots under 5" from 800yds out. At 1000yd, top scores weren't much worse and the winds did pick up.

At the top levels of F class, nothing is left to chance.

Jerry
 
Mystic Precision said:
At Raton and every other range I have shot out to 1000yds, the smaller bullet was simply punished more for small wind reading mistakes or in bumpy air.

I am not saying the 308 shooters beside me didn't get moved around but when they got bumped into a high 10, mine was a higher 9. Same direction.

Comparing starting winds and wind useage, my adjustments mimicked the 308/185 over several shooters. We both made the same conclusions about the left and right BUT it was the bumps up and down and gusts that hurt me much more.
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Jerry, how do you know that your .223/90 bullet was being pushed more up/down than a .308/185? I know you think you saw it happen to you in Raton, but how can you be sure from your observations that your lighter-but-equal-BC bullet was being pushed similarly left/right but more up/down? Here are some explanations I can think of that are consistent with your observations:

1 - your idea that a heavier bullet gets blown up/down less than a lighter bullet of the same BC

2 - just some bad luck. What if, on the occasions where some "vertical wind" happened, you were simply unlucky and happened to fire a "high in your group" shot when the wind gust came along that pushed your bullet up, or a "low in your group" shot when the down-pushing gust came along? Of course the more occurrences you observe, the less likely it is that "just some bad luck" is a plausible explanation.

3 - your .223/90 ammo had a larger vertical spread at 1000y in no-wind conditions than your neighbours' .308/185 ammo. You do say " my 223/90 have little to no vertical and shoot great accuracy, but just what sort of typical or average groups sizes were you able to achieve in testing? Ideally, groups of 10-15 shots, at 900m more or less, in benign conditions (though I realize it is a tall order to arrange for much shooting opportunity like this). If you were able to do any training at 900m/1000y on an F-Class target, what sort of typical X/V-counts were you able to achieve under favourable conditions? If your ammo shot 7" groups at 1000y and your neighbours' .308/185 ammo was able to shoot 4-5" groups at 1000y under excellent testing conditions, it could simply be that your slightly-taller groups lost you a few more points to elevation over the long haul (which is what would be expected).

Mystic Precision said:
Same can be seen in Open where the smaller cals simply bleed more points vs the big heavy bullets at 1000yds. All of the BC's vs muzzle velocities are very close. The larger heavier bullets do not get bumped as much by localised winds or gusts.

There are other shooters around the world who have also tried to exploit the 90gr BC/muzzle velocity vs the 308 and have all given up.
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It is true that the smaller F-Open cals bleed more points than the larger ones - but the BCs/m-vs are not "very close", there is a consistent "house advantage" (a higher BC all other things being equal) that consistently accrues to the larger calibres.

I agree that we have not seem very much success with 223/90 in competitions, in spite of the fact that a good number of very competent loaders and shooters have tried pretty hard to make a go of it. This doesn't mean that "light high BC bullets have more vertical than heavier bullets of the same BC and MV", a much likelier explanation is that there are problems with the 90 grain bullets and/or the .223 case/bore/primers/etc that somehow prevent robust accuracy from being achieved.


shockman said:
...but I do know some old timers that say heavy wins out because of some unwritten enertia or somthin!! I have Litz's book but have not read it enough to determine if he talks about this phenom. My only experience is with 6mm 105's, 6.5mm 140's, and 7mm 180's. With these 3 calibers, 6br, 260rem, 284win, it appeared to me that they were all pretty true to their BC's.
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Old timers may well believe that, but that doesn't make it true. You should definitely listen to everything old-timers say, however everybody makes mistakes so you have to carefully weigh even their opinions.

I don't recall Litz's book talking about this (there's only so much that can be covered in a given amount of space, and it's not a very technical book). Litz understands standard ballistic modelling quite well, and I would be most surprised if he were to hold a different opinion on this than mine (which is just a straightforward application of the standard assumptions that go into point-mass exterior ballistics modelling).


Mystic Precision said:
Ballistics program can only calculate steady state situations and constant variables (there is an oxymoron). At mid range (600m), the ballistics really work well for the most part and light/fast can keep up with heavy/slow. But extend that to 1000yds and the difference is obvious.

Just shoot the stuff on a breezy day and see for yourself.

In BC, we have some of the BEST 6mm shooters and wind readers in the World. Ask them their thoughts between their 6 BR/Dashers and 6.5/284's and 30cals. Some have done superbly at 900m with a 6BR but they all seem to want to compete with 7's now.

Inertia helps you with the conditions you do not see along the bullet path. Liking hitting a gust of wind on the highway - usually, the smaller vehicle gets buffeted more.
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Ballistics programs and models can be used for non steady-state conditions. For many interesting questions in applied ballistics, a straightforward ballistics model (e.g. JBM) can be used to gain a great deal of insight, especially if you have some understanding of the underlying assumptions in the models and what the limitations are (and where the modelling is quite valid).

While your analogy of a small vehicle encountering a gust on a highway is appealing on first glance, it is not an apples-to-apples comparison with what we're talking about here. The weight of the small vehicle would have to be proportionately higher than the larger vehicle (in accord with cube-square scaling laws and drag coefficients), in order for its 'BC' to be comparable.

These 6BR shooters are currently shooting a bullet of G7BC ~= 0.27 (Berger 105 class) at say 2900fps. Ballistics says 7.4MOA of wind drift at 900m for a 10MPH wind in std. atmosphere.

Are they hankering to shoot a 6.5mm firing a Berger 130VLD (G7BC=0.28) at 2900fps, i.e. basically the same "on-paper" ballistics? Or a Sierra 142 (G7BC=.301) at 2650fps (same on-paper 7.4 MOA wind drift at 900m in 10MPH wind as the 6BR/105, but with a 142 grain bullet instead of a 105)?

Or when they think about shooting a 6.5mm or 7mm instead of a 6BR, are they thinking of shooting the very heaviest best designed highest performance bullets available to them, at the highest practical speed out of one of the known-good big F-Open cartridges? This would not be a case of seeking "a heavier bullet but the same on-paper ballistics as a 6BR", this would be the right way to go about seeking more outright performance than a 6BR can deliver.

kombayotch said:
Not my experience. The 115 DTACs in my Crusader have probably been the easiest combo to tune that I have ever fired. I've run several barrels to over 2000 rounds without ever adjusting seating depth. This group was fired on an old barrel after minimum development with 117 Matrix VLDs.

...snip...deleted nice photo of 2" 10-shot group at 300 yards with 2000 rds down the barrel...

A 6 SLR is not going to keep up with a big 7mm driving the 180 hybrids though. The Crusader comes close, but its a bigger case (6mmAI).
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Very nice group, amazingly nice considering that it's from such a big (6mmAI) case with 2000 rounds down the tube; "expected" F-Class barrel life from something like that is usually well under 1000 rounds and yet this group is "more than good enough" for a great, great many applications. Your group is 2/3 MOA though it has a "core" tighter than that(just under 1/2 MOA). Is that typical accuracy at that stage of the barrel's life, or a "notably good" group? When the barrel was new (500 rds and less), did it shoot any better than this? (my I've-been-out-of-F-Class-for-11-years opinion is that one could do reasonably well in F-Open with a rifle that grouped like that, but it would not quite be accurate enough to reach the top tier).
 
kombayotch said:
Not my experience. The 115 DTACs in my Crusader have probably been the easiest combo to tune that I have ever fired. I've run several barrels to over 2000 rounds without ever adjusting seating depth. This group was fired on an old barrel after minimum development with 117 Matrix VLDs.



A 6 SLR is not going to keep up with a big 7mm driving the 180 hybrids though. The Crusader comes close, but its a bigger case (6mmAI).
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That is some fine shooting for sure but assume that this was under ideal conditions?

In F open today, 300m groups need to be a whole lot tighter with far less vertical. At longer distances, many of those wide shots in your group might get a whole lot worst. The only way to really know is to shoot it at paper and have it scored. If you can't center the group and score well (or at least as you expect), the barrel is toast.

If the goal is to be able to hit the 5 ring, 4 ring if a bad wind call and let the V's sort themselves out, have at it. Barrels can last a good long time. If the goal is to be able to hit the V bull on demand, things get far more demanding.

Jerry
 
For F-Open, you're shooting off of a big heavy rest with a rabbit ear bag at the rear. This was shot off a Harris bipod with a simple "soup can" bean bag in the back. After 2k rounds on the barrel, I'm not going to complain, the barrel owes me nothing at that point. But to say that it's accuracy is horrible, is hardly true.

Winds were light on that day, and it was a test group, so I wasn't making adjustment to try an center the group on the circle. When the barrel was newer, it would easily keep 10 rounds in a 1" group at 300 yards.

The barrel I shot at NSCC this year had over 1600 rounds on it, and I came in second. None of the 6.5-284s there did better...
 
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Here is what tuning a 223/90 can look like. This was at 500m. Real time so just scroll through the video to get to the end. Not a calm day but not a bumpy day either.

Believe me, I have invested massive resources to make the 223 work (there is a massive post somewhere in this forum of my journey). I have no need for recoil and guided by paper ballistics, I went for it.

How do I know that I was getting punished more then a 308/185? Cause I was shooting next to them and watching their targets vs mine. It most certainly was not just vertical that killed me but windage. The ability for me to hold center just got tougher and tougher the further I went. Now you can say a better wind reader would have done much better with my rifle. I would certainly support that as my time at 1000yds is limited but we see shooters from all over the world bumping into the same problem.

Some very fine shooters have tried.

Could it be a bullet design? maybe but there have been at least 4 90gr bullets tried. 3 of the 4 share varying planforms so it can't be tied to one wonky finicky shape or even quality control as lots of bullets have varied over the years.

Sloppy loading tech? doubt it as these top shooters load to same level for all their rifles. you don't get group like I did by winging it at the bench.

The light went on when I was in Raton last Sept shooting with some top US shooters. One used a 155.5 and another a 200gr. The difference in outs was obvious. Comparing the lighter bullet to all the heavier slugs shot close by you could see the trend hit ALL targets, but the lighter slug was pushed further. Given the status of shooting and wind reading skill of this shooter, I doubt she just "missed" a call.

So my conclusion was to set up for 308 in FTR for the Worlds this Aug and wow, what a gong show that was to go from no rifle to competitive in a few months. Learnt a lot along the way and since I am looking at the target with both sets of experiences, I can say with complete certainty, despite my desire to have the 223 be competitive at LR, it simply isn't. But it can work very nice at mid range and as a practise rd.

In both classes we are seeing a simple situation of "enough". At a certain BC and bullet mass at 1000yds, the shooter can launch a system that arrives true to their expectations. The bumpy air simply doesn't have enough effect to really make one go WTF too often. Whether that is a 308 heavy in FTR or 7mm/180 or 30/210 in Open, it is simply enough and trying for more usually leads to other problems tied to gun handling.

If we only shot to 600yds, the top choices would be very different as would be those used if we shot out to 1400yds.

We are narrowing our tech to suit a game with a set of requirements. We are all working to find "enough".

Jerry
 
kombayotch said:
For F-Open, you're shooting off of a big heavy rest with a rabbit ear bag at the rear. This was shot off a Harris bipod with a simple "soup can" bean bag in the back. After 2k rounds on the barrel, I'm not going to complain, the barrel owes me nothing at that point. But to say that it's accuracy is horrible, is hardly true.

Winds were light on that day, and it was a test group, so I wasn't making adjustment to try an center the group on the circle. When the barrel was newer, it would easily keep 10 rounds in a 1" group at 300 yards.

The barrel I shot at NSCC this year had over 1600 rounds on it, and I came in second. None of the 6.5-284s there did better...
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Not saying anything is good or not. You run the gear that suits your end use and if it is competitive, its all good. I would love to shoot the NSCC someday but given the tasks, pure mechanical accuracy is NOT the main priority. F class targets don't turn away :)

The key measure is how many rds before your barrel STOPPED plunking them into 1" at 300m. If the goal is top placings in F open today, the gear has to let the shooter hold the V bull. At some point, the V bull becomes more luck then design and the competitor then has to decide if it is time to change.

Yes, barrels are considered "worn" when they hit 1/2 min or slightly larger - remember that the score is affected by wind so to ensure hitting the target, you have to be more accurate then the target. F open rigs are hovering in the 1/4 to 1/3 min range at distance. That level of accuracy doesn't last long.

YMMV.

Jerry
 
Different shooters firing at different times, while making scope adjustments is far from a controlled experiment. If you want to compare them in an accurate way, you need to fire them at 1k in a round robin sequence under the same condition with a fixed wind setting on the scope. Then calculate out the actual drifts.

Example of how to do that here:
http://www.canadiangunnutz.com/foru...sted-1k-New-155-Palma-155-5-Berger-155-Scenar

Note Mr. Litz's comments about people drawing conclusions from superficial observations, without taking good data.

I am more inclined to believe that the root of the issue is the inconsistencies due to the smaller case and smaller components, as decribed in the article above. A controlled test would tell you for sure.
 
SND said:
Reading that article certainly didn't motivate me to switch to F-tr... kinda like the 6.5's.
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Two different games with similar goals. Kind of like NASCAR and Indycar. I moved to FTR cause I wanted more stability in gear and reduction in costs.

The 2 things I know for sure - I don't need to lug a 40lbs rest around and my barrels last twice as long (didn't say they lasted LONG). Beyond that, the needs have reached similar levels of complexity.

When FTR shooters can hit scores as good or higher then Open guys in a place like Raton (shooting on the same relay), you know their skills and gear are superb.

Growth in FTR in many parts of the World would suggest that this is where the toughest levels of competition are likely to be going forward.
Jerry
 
Mystic Precision said:
Here is what tuning a 223/90 can look like. This was at 500m. Real time so just scroll through the video to get to the end. Not a calm day but not a bumpy day either.

Believe me, I have invested massive resources to make the 223 work (there is a massive post somewhere in this forum of my journey). I have no need for recoil and guided by paper ballistics, I went for it.
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I know that you are one of the shooters/loaders out there who put a major effort into getting 223/90 to work. It was a very promising bullet and I am grateful that you and others have put so much into trying to get it to work - had it been successful it would have been a really good improvement to the state of TR and FTR shooting. It's a shame that it looks like it's not going to work out, but I really appreciate all the good work that you and others have put into trying to learn about it and get it to work.

I've watched that testing video of yours before and have enjoyed it, however at best it's just a tiny little teaser of 'this is worth looking into further', it by no means shows that a .223/90 shoots well and can be counted on. For one thing, it is a single five shot group. Is the other group on the target (perhaps 3/4MOA) at all related to the ammo being tested on the right target, which puts five shots into essentially zero vertical?

A ten or fifteen shot group, or three 10-15 shot groups, or five consecutively-fired 5-shot groups, would start to tell a lot more about how the ammo/rifle is shooting - what is the _typical_ or average distance a shot is from the group centre? how far out are the worst shots in a string of 15 or 20 shots?

Also, your testing was done at 500m. There's a lot that can be "wrong" in ammo and still be able to shoot really good groups at 500 and 600 (specifically, you can have pretty middling velocity SDs and still be able to shoot very, very good groups at 500 and 600). If you want to develop 1000y ammo it's best to test it at 1000y if possible, though admittedly that is a tall order. The next best way is to test it at shorter range (100, 300 500 etc) that you have and set up so you're shooting over a chrono. If you shoot 1/2MOA or smaller groups at 100/300/500 and you ALSO have good tight velocity spreads over the chrono, you haven't proven that it will shoot well at 1000y but its a very good step in that direction and there is a very good chance that the ammo will shoot well at 1000y (but it's still a risk until you actually shoot it at 1000y under decent testing conditions)

How do I know that I was getting punished more then a 308/185? Cause I was shooting next to them and watching their targets vs mine. It most certainly was not just vertical that killed me but windage. The ability for me to hold center just got tougher and tougher the further I went. Now you can say a better wind reader would have done much better with my rifle. I would certainly support that as my time at 1000yds is limited but we see shooters from all over the world bumping into the same problem.
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With respect, and truly I mean it when I say with respect when I ask you this question, how much individual and team shooting experience do you have? I.e. how much can you trust your ability to assess your own performance as a shooter and as a wind-coach?

I know that the 223/90 seems to have turned out to be a 'great idea that has failed'. But that doesn't mean that that is evidence of a new aspect to exterior ballistics, i.e. that there is an "inertia effect" due to bullet weight that is above and beyond that which is already worked into the "BC" modelling.

Could it be a bullet design? maybe but there have been at least 4 90gr bullets tried. 3 of the 4 share varying planforms so it can't be tied to one wonky finicky shape or even quality control as lots of bullets have varied over the years.

Sloppy loading tech? doubt it as these top shooters load to same level for all their rifles. you don't get group like I did by winging it at the bench.
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The commonality is that they were all .224" diameter 90 grain bullets fired from a .223 Rem case. They all use a small primer, and a relatively small case. Whatever dimensional accuracy the bullet makers are able to achieve, small but unavoidable errors/tolerances in a .224" diameter bullet (especially one with a long bearing surface) are proportionately more important than an absolute error of the same size in a .264" or .308" diameter bullet.

What do the raw measured numbers show (both yours and others')? What were the short range (100y) group sizes, what were the muzzle velocity ES/SDs? If these are middling, there's little hope of seeing match-winning performance at 1000yards.

What were 1000 yard group sizes achieved during testing in favourable wind conditions? Before you even take wind into account, first you need a rifle that shoots an "adequately tight" group for the game you are shooting. If you're not able to reliably get about 1 MOA 10-15 shot groups at 1000 yards when the testing conditions are favorable, you have a rifle that isn't quite up to snuff for iron sights shooting at the top levels of competition. If you want to shoot F-Class at the top levels of competition, 10-15 shot groups that are 0.7MOA or bigger mean that you have a middling rifle not a great rifle; you better be getting 0.6MOA or even better 0.5 MOA if you possibly can, if you want to be competitive at the highest levels of the sport, because many of the other topnotch FTR shooters are getting that level of performance.
 
All excellent points for sure. The testing I have done has been what I feel exhaustive and likely should have stopped long before I finished but that is just me. Let's just say 4 barrels have been put to bed. And Yes, I shoot to over 900yds.

The issues I present are based on my "gut" feeling. Take it for what it is. It just happens to mimic the opinion of shooters I have never met in other parts of the world. As for my shooting, I feel it is solid. I know when I am doing it right and when I am not. Wind reading has always more to go but above average for now.

Ultimately, F class or any precision LR sport boils down to good solid gear, quality ammo, an experienced shooter who knows how to read the winds. Many concepts have been tried and only a few seem to stick around.

The 6.5 in its many forms is likely the longest running experiment for Open. With the advent of quality 7mm and mid/heavy 30's, that debate is now over at 1000yds. It will continue on in mid range.

The 223/308 debate may continue in FTR. At this point in time, there is just too much working in favor of the 308 to continue with my preferred chambering at LR.

If someone figures out a better bullet or how to mask what I see, I am all over it cause there are way more pluses in a small case. Error and tolerance will be part of our sport no matter how advanced. The key is at what point does mechanics not matter?

Testing over a chronie has very strong merits but how many chronies actually have tolerances that make the numbers it generate worthy? I am hoping a new chronie has that level of resolution but I will always back it up with holes in paper.

The question of the post was heavy 7mm vs heavy fast 6mm. At 1000yds, there really isn't a debate or me. Shoot whatever you want and hopefully, it does what you want.

My experience shows that you can't push a lower BC bullet fast enough to gain you enough at 1000yds to keep up. Add in the bore wear and tuning issues, and it becomes a system far more demanding then most will want.

Now shooters are figuring ways to get high BC HEAVY bullets going fast. That is simply too much of a ballistic advantage to ignore. Will ballistics win you matches... NO. But it sure helps when you can get it.

Jerry
 
Mystic Precision said:
...
The 6.5 in its many forms is likely the longest running experiment for Open. With the advent of quality 7mm and mid/heavy 30's, that debate is now over at 1000yds. It will continue on in mid range....
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Did not Larry Bartholome win the US F-Open Nationals at Raton this year with his 6.5x284 or is he shooting something else these days?

The other factor is range templates. Those of us who shoot Connaught cannot drive 7mm/30's to some of those higher velocities posted.
 
lejarretnoir said:
Did not Larry Bartholome win the US F-Open Nationals at Raton this year with his 6.5x284 or is he shooting something else these days?

The other factor is range templates. Those of us who shoot Connaught cannot drive 7mm/30's to some of those higher velocities posted.
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Wish there was a gear list but afaik, no top US shooter is using anything but a 7mm or 30cal.

The US teams were all on 7mm of varying types. A few brave souls were pounding 30cals but I don't think they shot in the team match with them?????

FTR was 308 except for 2 - 223's (maybe 3).

Yes, there were a few 6.5s but unaware of anyone in the top third using it.

Even the Connaught template will allow these larger cals to fly. Not as hard as some are moving towards but plenty fast enough.

A 230gr hybrid at 2800fps. 180gr Hybrid at 2950 Nothing to sneeze at.
Jerry
 
The Connaught template maxes out for a 7mm 180 Hybrid at 3015 fps. Not fast enough. No point in using a WSM or RSAUM. You can drive a .284 Shehane close enough to that with less powder.
 
I always knew that F-Class would end up with the 7mm/30's as the ballistic kings for long range.

I just need to expend the 2,000+ 6.5mm bullets I own and get on with reaming a .284 barrel later.

Any real world difference between the standard Win .284 and Shehane case?
 
I built a new rifle this year and toyed between the 284 Shehane and the straight 284. I went with the straight. It was my understanding that you could get about another 100 fps with the Shehane, but the added cost of the dies didn't do it for me. I'm running 55 grains of 4831Sc with a 180 Berger Hybrid at around 2850fps. After playing with seating depths most of the summer, I am getting around .9" 5 shot groups at 300 yards. The nice thing is that these speeds are really easy on brass and barrel.
 
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lejarretnoir said:
I always knew that F-Class would end up with the 7mm/30's as the ballistic kings for long range.

I just need to expend the 2,000+ 6.5mm bullets I own and get on with reaming a .284 barrel later.

Any real world difference between the standard Win .284 and Shehane case?
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Really expensive dies :)

Personally, I have worked with the 7 Mystic which is my version of the 280 improved. No better no worst. Just can use 30-06 brass and lower pressures vs the speed.

Same as the 7RSAUM. I am not a fan of using small cases at high pressures.

The 284 and shehane now have a strong track record for success. They work and we know how to make them work. 2800/2900 is a perfect speed node for the bullet and everything else. Simple.

Another 100 to 200fps looks good on paper but tuning, bore wear, component costs may not be everyones cup of tea.

This definitely falls into the category of ENOUGH... nice set up.

Another great option is a 30RSAUM/ 30-06 improved with a 200/210gr VLD or thereabouts. Should offer better bore wear and has proven to be very simple to tune.

Eeny, meeny....

Jerry
 
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