Another 6.5-47 Thread

R

roberti11

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I took advantage in a break in the southern ontario weather this weekend to try out some new loads in my 6.5-47 Lapua.

I have tried alot of powder and bullet combinations but my best results have always been with Lapua 123gn Scenars and H4350, I have used this load in several competitions and found it to be very reliable in all seasons. Recently I picked up a keg of Hybrid HV100 to use in one of my other rifles. After reading some favorable comparisons to H4350, and because I have a keg of it, I decided to try it in my 6.5-47 . This powder meters very well, and I really did not have to trickle very many of the charges after they were thrown. I was a bit concerned with density, the ideal load looked like it was going to be 108% compressed.

I have posted the results below compared to other loads including alot of data with H4350. In my rifle this powder is an excellent replacement for H4350. I would not say that it is any better than H4350, but it is at least as good. I plan to use it for the rest of the season and see what happens in the heat of summer





6547L.jpg



Rifle is a 1:9 twist Gaillard bbl, 29 inch Palma contour.
Stiller TAC 30 action, in a Macmillian A5. I use this for ORA precision matches, and have been happy with performance out to 800 yards. I have not used this for distances longer than this.
 
Max Owner said:
Is there a parent case or a ground up designed new cartridge?

The net isn't telling me so ground up designed...................?
Click to expand...

From the link I posted...

"Lapua developed the 6.5×47 Lapua cartridge for International 300m competition. Lapua wanted a cartridge that could match the “pure accuracy” of the 6mmBR, but with even better ballistics and good barrel life. The 6.5×47L is now really coming into its own. In the hands of NBRSA long-range Hall of Famer Don Nielson, the 6.5×47L has won two NBRSA 600-yard Nationals convincingly."

From what I have read this was a design from the ground up, hence the use of the small rifle primer, as far as I know it was not based on any specific exisiting cartridge.. Others may know better
 
No the basic design was dreamt up and shot decades ago. They even had small rifle primer brass to work with.

Not much today that wasn't wildcatted to some degree back in the 60's, 70's and 80's. Many of the commercial cartridges we enjoy today were garage designs in the 30's.

Dimensionally, the Lapua is very similar to the IMHSA series developed in the 70's for HG silhoutte shooting. The 6BR came from this sport too - no it was not a Rem invention.

Look up the work of Elgin Gates. Smart guy and really did alot of work on the 308 Win and Savage family of cartridges.

Brass alloy and internal design are changed a bit here and there for sure. Lapua has done a really nice job of reinforcing this case. But the exterior shape is nothing really new.

The Hrn Creedmore is the same thing. The same ole changed a few thou and degrees here and there.

Good and bad is a relative thing. If you want to move heavy bullets fast, you need case capacity.

The 6br is a wonderful cartridge but it can't do what a 6-6.5X47L or 6XC can do nor can these two do what a 243 reg and improved can do, nor can these do what a 6mmRem reg. and improved can do, etc, etc, etc.

For F class, I want to push the 140's over 2900fps without excessive pressures. I use a 260AI/6.5 Mystic case. Easy to tune, zip for vertical, repeatable and has worked great for me these last yrs.

There is no way a 6.5X47L can do the same without some seriously high pressures. I know I am in the 60,000psi range. I shudder to think what a Lapua would need to run at.

Is a 130gr VLD at 2900fps BAD? Nope, damn fine bullet but it does give up something to the 140gr VLD at the same speed when the wind starts to blow.

But then these give up something to the 7mm 180gr VLD at the same speed

etc, etc, etc.

Jerry
 
Jerry, as past BS between us besides, what will the 6.5mm do, what a fast 6mm won't? I am curious as to your reply, but no sh%t storm intended.
Thanks.
R.
 
The problem with 6mm versus the 6.5 is complicated.

The best 6mm bullet available in Canada as a factory match bullet is the 115 Berger. Its BC is actually less than the 224 cal 90 grain VLD! The problem is compounded by the fact that Berger has dramatically cut their 105 "VLD" BC. Lapua, Hornady and Sierra don't make high BC 105/7's and don't make anything heavier in 6mm

The selection of 6.5 bullets is much better with a G1BC of .600 or better. The 130 berger is in a class by itself with a G1BC similar to the 115 Berger, but with more mass,

You must get the 115 6mm going at speeds really only achievable with 243AI, or 6-284 wildcats to significantly exceed the ballistics of a 6.5 high BC bullet doing a modest 2900. There is an "Accuracy Barrier" with these heavy VLD bullets (such as the 115) ,and I can tell you from first hand experience that they are damned difficult to make work beyond 3000 fps.

The advantage of the 6.5 Lapua is its ability to make a 130 grain bullet work very well at good velocity, and with considerably better barrel life than any comparable 6.5.

Interestingly, a 22BR with a 90 grain bullet will (on paper) exceed the performance of a 6.5 Lapua and a 130 Berger, but at the cost of less barrel life, and the need to tune the load near red-line, which is always much trickier. The 6XC, 6 SLR and 243 will come close, and may actually exceed the 6.5 lapua/130, but at the cost of 1/2 -1/3 of the barrel life.

The 6.5 lapua is a classy round. I remain skeptical of its ability to push 139-142 bullets as well as the ubiquitous 260, but I can be convinced otherwise when someone can prove otherwise.

The only issue with the 6.5 lapua of which I am aware is the fact that I have been in contact with a number of people that have expressed frustration getting this cartridge to work well. The issue seems to be the fact that seating depth seems to be important, and by assocaition - the length of throat. I tend to suggest getting the chamber throated for the 130 Berger and work with those.
 
Rman said:
Jerry, as past BS between us besides, what will the 6.5mm do, what a fast 6mm won't? I am curious as to your reply, but no sh%t storm intended.
Thanks.
R.
Click to expand...

It all boils down to bullets, their drag and how fast you can push them.

Why the 6mm is out of whack with the other cals, I cannot say but it has the lowest BC bullets given the weight for the cal.

The 22cal 90gr Berger VLD is higher - that is nice but doesn't make sense.

Mechanically, the larger the bore you go, the easier it is to make lower drag bullets. So the 6mm is a mystery.

With all the techs and tweaks we have these days, you can make pretty much make any combo shoot as long as you don't exceed the speed/spin velocity of the desired bullet.

So, the highest BC bullets are going to get the interest.

The 140gr Berger VLD has lower drag then any bullet in a smaller cal. The new 7mm heavies beat the 6.5. The "New" gen 30's will beat the 7mm and of course the 338's lay a boot to everything smaller.

At some point, a new gen 6mm will be made which will bridge the gap that exists now and we will be back to balance in the universe. But that same tech will be applied to the 6.5 so it will still have lower drag.

For F class, the balance is always around accuracy, reducing wind drift and recoil. I don't include barrel wear or cost because those that are concerned about being on the podium will have the resources to make it happen.

The question is CAN they make it happen. I have no interest in a 180gr 7mm going 3000fps in a 22lbs rifle - just way too much fun unless someone comes up with a new recoil absorbing product.

So run some numbers through a ballistic program using Bryan Litz's new numbers. JBM is ideal. Just set all the parameters the same and just change the bullet. Look at the difference in wind drift for 2 to 4mph and compare that to the scoring rings or target you intend to shoot.

If a misread in wind still lets you drop the bullet on target, that is the combo that is going to win.

Here mechancial accuracy plays a much smaller role because the diff between good and great is still inside the V bull.

But getting pushed around by the wind out the back side of the target is very costly.
Jerry
 
I almost dare to say that F-Class has defined itself in the open class. 6mm, 6.5mm, 7mm. The bigger the case, the more velocity with bigger bullets which of course reduce wind drift, but add more recoil. The weight limit, range templates and lack of muzzle break shy everyone away from the big .338.

You can try all you want to use small cases, the latest VLD's and in good conditions you will shoot with the big cases and win too. The 6BR, .260AI, 6.5x55 and .284 Win, 7WSM all get the required velocities within their realm. I've always regarded the 6.5x47L as an in between case. The pressures required to match the other 6.5 cases are bordering excessive. There's no need to do that.

It's not the first choice for 1,000yds F-Class and won't be, but it's certainly fun to play with. I've been lucky on occasion to beat everyone with a .223 Ackley and 80grs Sierras @ 1,000yds on a single relay, but nobody was ever convinced it's the go to cartridge.
 
Berger will develop a Hybrid 6mm. Low on the production pecking order but the cries of sorrow have been heard.

But unfortunately, the potential of a 'small' cal keeping up with the 7mm and possible new 6.5's in F class at long range, is not good.

Resources are being put to exploit the bigger cals.

Jerry
 
Exactly! One can always develop slightly heavier 6.5 or 7mm VLD's like they did the 22 or 6mm that will even bring more BC's which gives the bigger cases the ability to drive them. If need be, bring up the pressures on the bigger cases and the smaller cases cannot compete there.

This reminds me of drag racing and small vs big block engines. In the end, the big block 426 Hemi fed with Nitro fuel blows them all away, but it's always with a cost. No free lunch.

I remember using the 6.5x284 and driving the pressures up with N-560 in a custom action gun. Recoil was getting fierce in an 18lb gun, but there seemed to be a point of diminishing returns with the components on hand back in the late 90's. I had the 140grs at speeds of 3,300fps or more. Like Jerry, I found that accuracy and ES seemed to hover around the 2,900 to 3,000 fps area with normal pressures.
 
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