Why no 7mms in LRBR Comps

[a.JR]

Hi All , Just looking at the Stats from 2010 in the 10 shot matchs both here and in the US, No 7mms hardly anywhere ,why;s that ..JR..Jeff Rogers

[albow]

because a 30 cal is so much better.......

Seriously I think that there are just so many more options for cartridge and bullet combinations for the 30 cals whereas for the 7 mils there probably isn't that flexibility although the couple up here seem to do pretty well with the right components

[Code4]

Just fads I suppose. Was there a time when 7mm's were more prevalent ? I would guess that in the late 60's there were more 7mm's and not many 6.5 or 6mm's, if any.

[macca]

I guess its a projectile problem.
I have had one good batch of bergers.
The 168gr Sierras are great on a good batch and then its best of luck.
Never found the good amax's and there aren't a lot of custom 7mm's that i have found.
I am being to doubt some of the bc claims made for some projectiles, .
When everything comes together I am reasonably competitive.
I think most top drivers have been there and done that so they have moved to the best choice for them.I am a relative novice and the 7mm was my first LRBR rifle and has done me good service so far.It has also won me a few comps in f open.

[steven]

It maybe because everytime someone mentions building a 7mm they are told they are no good because they have problems with 7mm's not being able to get the vertical out of them like a good ole 30.

Steve

[Tony Z]

I think the reason some calibers are a no show or are in decline is just simply because the days of experimentation at 1K are nearly over. The bullets are known, the twist rates are known, the capacities required to do the numbers are known. Playing around with something you like is great if you are in it for fun, but if you want to be competitive on the 6 or 10 match scale, the recipe is out there.
Personally i will never write the 7 mil off. I just reckon the formula has not been found yet. But with a very small choice of good bullets, is it really worth it to try to find out?

Way back in the early days of 1K, the idea was to get BC to do the winning for you. So the 6.5s and 7 mils where everywhere and in some very large and obscure cases. Since then two things have been discovered. Some of the BCs were over stated in those early bullets, and accuracy is way more important than BC, even at 1K. So the legacy or legend of some of these cartridges is what kept them about longer than what they should have been. It was only history that kept them about coupled with the odd good group. We can all recall the days when the 168 SMK was rated at a 0.620 BC. So why wouldn't you use it? Now it has been downgraded to under 0.5 by Sierra, but Litz has them at a little over 0.5. Still good but not great. Lots of matches were won with this bullet, but as soon as it got downgraded, no-one uses them. Proof that the accuracy they gave won matches and that the BC everyone believed they had contributed nothing except a belief in ones mind that the bullet was slippery. A good reason to remove BC from the first priority of what a 1K bullet must have.

There is a belief that 30 cal bullets and barrels are easier to produce to a very high standard as compared to smaller calibers. I don't believe that for a minute and if this was true, no-one would use a 6 PPC in SR BR. What i believe is that there is a minimum BC, a minimum velocity and a certain number of RPMs that produce accuracy in all sorts of weather conditions. I would say the 30s do all that better than others.

[petevm]

Interesting discussion so far. My personal thoughts are that in HG class I prefer .30 cal as there is a better range of bullets, cases and barrels to choose from, plus that extra.024" in hole size may pick up the odd extra point as well as a slightly more visible bullet hole in the fly shoot. For LG class the recoil of the 7mm has always defeated me (even the 284 Win), so the original choice was the very popular (down south at least) 6.5/284. Combines good BC of the 140gn bullets with good velocity (up close to 3,000 fps) and gives reasonable accuracy. However, for absolutely consistent top accuracy I also use a 6mm Dasher - similar velocity but lower BC (103 to 107gn). Given the often shitty conditions we have to shoot in it's nice to have the choice on the day - and don't forget that marginally larger bullet hole. (I even have a HG in 6mm Dasher available in case it's 'one of those days' - hasn't happened yet!)
I have researched a few stat's for our range (Eagle Park - near Melbourne). As anyone who has shot there will tell you, it's a bitch to get consistently good scores here in the 500mt Fly matches.

Only 6 groups ever under 1.6" - shown in the order shot -
2000 1.543" 30-404 Imp HG
2007 1.550" 6.5/284 LG
2008 1.395" 6mmBR LG
2009 1.254" 7mm RUM HG
2010 1.405" 280 Ackley LG
2010 1.307" 6.5x47 Lapua LG
Hard to pick a trend here - totally random!

Groups under 2" -
HG 12x - 4 with .30 and 8 with 7mm.
LG 11x - 1 with 6mmBR, 3 with 6mm Dasher, 1 with 6.5x47, 4 with 6.5/284, 2 with 284 Win.
Seems the 7mm's are alive and well in these parts.

Best HG target 58.3 with 7mm Weatherby Mag.
Best LG target 59.2 with 6.5/284.

Match totals over 240 points - 4 different shooters -
2007 241.04 6.5/284
2007 245.03 284 Win
2008 243.03 300 RUM
2008 251.01 7mm Jacko
2010 246.00 6mm Dasher
Hmm!! Hardly much of a guide is it.

Well, by now you will have worked out that at our range it's handy to have a bit of luck on the day! I hold a record of a dubious nature - the Lowest ever winning score of 115 points (second managed only 96). Yep, that was one shit day! Oh, and by the way, the stats come from all matches - both club days and championship shoots - a total of over 50 matches in 10 years.

Pete

[a.JR]

Hi All , Thanks for the input .. The reason i put up the question in the 1st place was in conjunction with the 10 shot matchs , the 7mm in the Fly obviously has it's place .. In Benchrest it's only the 1000yd comps that this appears , i don't know about you guys but i find the 10 shots changes a bunch of things ,when i was competing with a 7mm , it just seems harder to keep the whole 10 in one spot when in fact it should be easier because of gun handling and BC gains.. Talking to a recent US champ ,he stated he ran a 7 rem short a lot at the practices and test sessions in 010 in the hope of getting a better mouse trap ,at no time did it rival either of the 300WSMs he used during the season ,even the one he calls the Leaker was well in front.. If it was as simple as the .750bc x 3500fps ideal then we would all have a 7mmSHV with a 40 inch barrel and Billy Shehane would be richer than King Solomon...JR..Jeff Rogers

[Ackley Improved]

Just my opinion....

But down our way more LR BR is dedicated to 500m Fly.. not 1000yds. This means rifles need to meet the rules, i.e no muzzle breaks.

I know for myself to shoot a 7mm that will push a 175 to 2900-3000fps, in a 17lb rifle it would be to much, and many think this. Hence LG seem to be on the smaller side generally.

Then when you step up to a HG, they are overlooked by the 30cal, and with bullet choices and case choices seems like a logical reason why.

If muzzle breaks were allowed in 500m Fly, then I think we would see some bigger boomers in LG... Seems 500m Fly is Primary, adn 1000yd secondary.

Has anyone played with the 7mmSAUM or 300WSM necked down to 7mm? This would have to be gtting close to a good combo with the 180 bergers? Just hard to spend $1000 on a barrel plus then dies when all teh information is pointing towards the 300WSM as well. Why try something else when the data says a round like the 300WSM is the bomb!!

CHeers

[RDavies]

I currently have a 7mm barrel being rechambered a bit shorter to make light gun weight. It will be in 284 with a muzzle brake, so hopefully there will be one 7mm getting lots of glory this year.
I only went with 7mm as I have lots of 284 components to burn up before I switch calibers.
If it goes OK, I will try the new 180 Berger Hybrids, but otherwise, anything from 168gn Sierras and Bergers to custom made flat base bullets. I hear that Sierra is bringing out a new 180gn pill as well, so maybe the bullet selection will be better soon.

[AlanF]

...I have lots of 284 components to burn up before I switch calibers...

More information please .

[RDavies]

AlanF. I have a 6.5x55 Imp on the way, but am also thinking about a 6.5 WSSM, just to experiment. In the meantime I have plenty of new and used 6.5x285 brass to use up.

[AlanF]

AlanF. I have a 6.5x55 Imp on the way, but am also thinking about a 6.5 WSSM, just to experiment.

Should be fun - my preference would be the 6.5x55AI. I read one report with the WSSM saying they get volatile when loaded near maximum pressure. Its interesting that you're moving away from 7mm just when I'm starting to like them. And its also interesting that 7mms have become the calibre of choice internationally for F-Class, yet they've never really taken off in the US for 1000yd BR. I believe its because high BC matters more for slower shooting, especially Bisley style.

[RDavies]

As is the trend in Flyshoots and long range BR, with more electronic targets coming out in F class, a cartridge with less recoil and easier loading into the loading port might make it easier to shoot fast when conditions suit. Since we cant use a muzzle break in fly shoots, I will use my little Dasher for the 500M ranges and save the 7mm for shoots where I can use a brake.

[Tony Z]

So Rod, does this mean that there will be more right bolt left port and ejector actions in FClass? Sure fire way to get the money side of things to dominate FClass and have many at a disadvantage with the likes of old Omarks etc.
Surely a simple delay of 15 or 20 seconds between displays of consecutive shots would slow this machine gunning approach, or is this the way shooters want it?
These days with the fickle winds and such at our home range, you rarely see a machine gunner shooting 1K. It is quite common for shooters to count the clock right down to the last few seconds of the 10 minute record period. Five years ago, if you took a minute to shoot 10 shots with a HG, JR was 40 seconds into his cleaning routine