1000 yard calibers.

1000 yard calibers

And one more thing. I would have prefered a shorter chamber. I have to load at 2.93-2.94 to touch riflings but my mag length is for the standard short action (2.80) This desn't seem to affect accuracy too much as I use neck sizing only.
 
Just about all the 6.5's, my 6.5 Mystic included push the 139/142gr class of bullet between 2850fps and 3000fps. That seems to be the best velocity for this family of bullets. 2900 to 2950fps seems optimum.

Been using Gaillard barrels as well and they love the Lapua's. Mine are 8.5 twist. Whatever Ted did up as his standard 6.5 twist.

Just note that although the 6.5 X47L has arrived with much fanfare, shooting is showing that some barrels will not take this reduced case size as fast as some shooters want. Most like a 2900/2950fps velocity range and some are finding the Lapua falling way short of that if match accuracy is desired.

Also, faster and hotter powders are needed to fit in the case and still produce the energy for reasonable velocities. As some are finding with the 6XC, using these fast/hot powders at elevated pressures is actually INCREASING throat wear.

On the positive, the small primer doesn't seem to be causing irratic ignition at this case volume. Ideally, this cartridge works best with the lighter 123gr bullets. It makes a wonderful 600m cartridge (its original design goal).

I think we will start to see increased barrel life in the 6.5-284 as shooters look at much slower burning powders. Right now H4350 and H4831 are the top choices. Both offer very low charge density in this case size and 'higher' wear. Not good things. Testing with the likes of H1000 will help with both.

Personally, I feel the 6.5 Mystic/260AI/6.5Swede to be ideal case volumes for this bullet weight and cal. You get very high load density and enough case capacity to reach 2900fps without crazy pressures. Big bonus is you are likely to use 10 to 15% less powder then common 6.5 -284 loads.

At present, my 6.5 Mystic has digested 900rds and moved the throat about 20thou. If the wear continues at this rate, I should be able to push 2000 to 4000rds through the pipe and still seat my bullet with good neck support. Setting back should give another 1000 to 2000rds more shooting.

Not bad at all.

Jerry
 
1000 yard calibers

Why all this complicated stuff?
my 28 inch gaillard produces 2880 fps (clocked) with 139 scenars (44.5 gr H4350) I'm past 2000 rds count with no sign of reduced accuracy.:)

Ok, then let's get to the more serious stuff. We need a 7mm bullet at 3000+ fps to stay well above the transonic range at one mile. Say a 180 gr Berger VLD (BC = 0.7) My 7mm STW does that (27 ½ inch Broughton 5C barrel, 9 inch twist) but if you prefer the short action stiffness in a single shot for F-Class why don't you try a 7mmWSM? It won't cost 80 grains of powder.
BTW before anyone asks, my Abolt CSS doesn't kick so bad especialy with a decelerator pad. Barrel is sporter magnum contour. Good for 3 accurate shots.
I think it's the best sniper rifle compromise. It will match the 338 Lapua ballistic trajectory with less kick.

Sniper767
 
The 6.5X47 Lapua was designed, as was the 6MMBR, for 300 Meter shooting, not 600M, but both will shoot well at 900M. The 6.5X47 obtains V comparable to the .260Rem.

I have not seen reliable data on barel wear/burning rate, but have asked that question of the test engineer at Nammo Lapua Oy. Will post. Really, it is throat erosion that is of concern, and powders of the same burning rate may erode differently, but I have no data on that.

Regards,

Peter Dobson
Hirsch Precison Inc., Lapua in Canada
 
Peter, you are right. The Lapua was set up for 300m comp. The Europeans tend not to shoot much further. However, I think the Lapua would be ideal for 600m.

Visit 6mmBR.com for quite a bit of discussion on barrel/throat wear as it relates to powder/pressure. Some interesting trends are forming.

The big difference is that the 260 can run H4831SC while the Lapua will likely lean towards the H4350/Varget/Re19. There are quite a few shooters reporting elevated throat erosion when H4350 is used at elevated pressures in small cals.

Conversely, wears rates are reported lower with larger cases while burning more grains of slower powders like H4831SC and H1000. Yes, it is all very new so nothing is conclusive.

Love to hear how your rifle turns out.

sniper767, you might want to look at the new center feed mags offered by Savage. Mine will digest a OAL of 3.0" and handles the sharp shouldered wildcats with ease.

Jerry
 
Jerry:

I Look at 6mmBR at least once a day. Great site. For throat erosion, other than the basic, I will rely on Lapua and its subsiduary VV, however, they will only comment after many thousands of rounds of controlled testing.

From what I have read on 6mmBR, the 6.5X47 is good to go to 1000.

Regards,

Peter
 
Jerry, the mention of small rifle primers reminds me of discussion arising from an "inquiry" stating that SRP would not perform as well in cooler weather. The 6.5X47 was tetsted in temperatures from +20 to -20 deg. C for V, pressure and accuracy. Works fine. The reason for the small rifle primers is that more material is available in the base of the cartridge case, hence it is stronger, allowing more pressure, hence V, as per 6MMPPC experience. Prototypes had LRP. An accuracy concept is that the best primer is the one that reliably ignites the charge with least "explosion". The 6.5X47 Lapua can be loaded hotter than comparable cartridges, because: 1. Lapua brass is tougher in the case head. 2. Small rifle primer. 3. It was designed that way and registered with CIP as such.

Regards,

Peter
 
throat erosion should be proportional to the flame temperature of the powder. 4320 and 4831 have two of the lower flame temps, while 4350 and varget are the highest of the single-based powders. Ball and Reloader powders (and VV 5xx) powders are double based with nitroglycerin, and burn very hot.


I'd like to find some literature from the powder companies wrt to the flame temperatures of their various powders at a variety of pressures.
 
Peter, this case better make it to 1000!!!

I would expect at least 1500 at peak accuracy before needing a set back. Still too new to get wide spread feedback. We will know a whole bunch more after the '07 season.

Love to hear what the good folks at Lapua/VV have to say about throat erosion. Not something US powder companies want to talk much about. I guess the fear of being labeled a barrel burner causing loss of sales is a huge deterent.

Plus one application could be great (varget in a 308), and another (H4350 in a 6.5-284/6XC) a dog. Lots of variables.

I read about the small primer 'issue' way back when the 22Cheetah was being developed using 308BR brass. With those powders and that case volume, shooters were getting alot of hangfires in the PD fields. Temp was rarely an issue.

With todays extruded powders, ignition is easier and more stable. However, irratic ignition came up immediately from shooters who remembered past experiences. Glad to hear it is not a real world problem.

The smaller primer pocket does lend well to 'BR' pressures. It is a very nice and technically savy case design. Albeit a very expensive 'small' case. I am really surprised it didn't come out as a 6mm version.

I guess they love the 6.5's more (Scandinavia - like 6.5's, never would have guessed).

Jerry
 
I have used my own .260 AI reamer with the best results. 2,900fps with 46.0grs of N-160 and a moly coated Sierra 142gr. or Lapua 139gr. I have worn out a McLennan 1-8.5" twist after 5,000rds., but getting Rob's barrel are very slow.

I'll probably try one of Gaillards barrels when the 40X .308 barrel dies next, as the US importing is a pain.
Always been a believer in the 6.5mm because IMO it's the best ballistically and easy on recoil for 100+ rds a day. 6.5x.284 is a good choice, I love the 6.5x55 Swede better. My .260 AI almost matches the 6.5x55 case capacity.
 
1000 yard calibers

Jerry:

what's this center feed mag business offered by Savage?
I can't find it on google. I use a Brownell's mag extension on my 2 Rem 700s.
It's only 18$ US ea. I know Badger Ordnance makes a detach mag system with 5rd and 10 rd mags but it's 500$ US (with one mag of each) and requires some inletting. I didn't think it allowed for longer rounds than the standard 2.80 SA. Last june I was in a sniper match (TAC-PRO) in TX and was loading my 308 154 scenars at 2.82 to get close to lands in my match chamber (reamer #3) they touch lands at 2.84 but I was pushing my luck as the clearance in the integral mag was near .020 only. I'm talking 308 in a palma twist madoco barrel here. I had to use the 154 LPs or 155 SMKs with that twist.

I'm sure some others would love to find out about this mag system that can feed near 3.00 OAL rds for a short action. It would do great in my 260 (as long as it doesn't cost an arm and a leg)

thanks in advance for the info. And forgive me if I was pulling your leg with that 260 stuff. I'll leave you guys alone with your fancy calibers.:)

Oh, btw, do any of you guys segregate bullets by the length of straight body? And do you meplat trim your bullets? I do the SMKs for 1000 yds shooting but find that the scenars don't normaly need it.

Serge
 
sniper767, I am surprised that more of our 'fancy' cals are being used in tactical shoots. I have seen quite a number of really nice rigs set up with cals like 243, 234AI, even the 6BR and family. Maybe their form of shooting has different rules.

Many in the LR game are measuring and trimming their bullets. Mostly this is due to the poor QC of one major bullet maker. There was so much variance within a box of bullets, without sorting, they would spray all over the place.

Personally, when I pay alot of money for a match bullet, I want a match bullet. Sorting, measuring, weighing, trimming simply means that the bullets are no where near consistent enough. Plus the loss of bullets due to culls raises the cost again.

Now for the kicker. If the bullets are so inconsistent using techniques you can measure, what about the insides of the bullet where you can't? That just poses a huge lack of confidence on my part and confidence is what helps me hit the X ring.

Sorry for the rant, but a huge irritant for me. I will only use a brand and style of bullet that shoots match accurate straight out of the box. Good news is that this major is improving QC with prime bullet weights so hopefully, this whole sort/trim thing will become an interesting anecdote.

For me, my bullet is the 139gr 6.5 Lapua Scenar (Hornady isn't bad either and just starting to play with Berger). I have played with 6 different lots of bullets manf over a number of years. ALL boxes shot to the same POI, same accuracy, same velocity using the same load. Even mixed bullets from different boxes but couldn't get them to open up the groups.

Now that is a match bullet...

As to your orig question, any new front release D mag Savage is center feed. I am waiting for some enterprising company to start making larger cap mags and this platform will pretty much take over the Rem in any mag feed game. And that will include LE and Mil applications.

Tactical style composite stocks to take this new mag/action are already being produced. I am sure HS and McM will see the light once feedback becomes more common.

That center feed mag is smooth and fast. Not as good as the AI (I doubt anything will be) but really really close. I prefer the Savage because you can feel the 'weight' of the bullet so you know you have picked it up. The AI is so smooth I have to check to make sure a rd has been chambered. I think the AI is too good.

Now the best part, ALL 07 Savages even with the blind mags, will be center feed. I believe only the Stevens line will continue the staggered mag.

These new Savages will have a slightly different action and certainly stock inletting. Otherwise, all the good stuff that makes Savages rock.

In some 07 varmint/target models, the Accutrigger will be able to go well under 1lb...safely.

Jerry
 
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I prefer whichever gives the best brass. Of course it depends if the action you have can handle either/or the case you want. Also the .280 will give you more velocity for long range. Do you need that extra velocity or not? Barrel life always decreases with more powder up the pipe.
 
I am really enjoying my 7 Mystic which is my version of the 280AI. Pushing 162gr AMax to 2950fps with very nice accuracy to 1000m. Will be testing some 180gr Bergers once the snow melts. 24" Shilen with a 9 twist.

I feel that the 280 and AI case volume is ideal for the heavier 7mm bullets. You can use the 7-08 very effectively and the 10 twist will limit the bullet weights you can use.

So if you don't plan on going that far, the 7-08 or AI will do very well. If you plan on pushing the range as far as possible, I prefer the Mystic/280size case.

The difference would only be about 150fps.

Ardent is having some fun with a 7-WSSM so you might want to have a look at that too. Then there is the 284Win which is also a very nice case size.

Jerry
 
kell2784 said:
What would you guys recommend for a new project, using a 7mm 162 grn amax in a 1 in 10 twist barrel? A 7mm-08 or .280AI? I'm debating back and forth, and change my mind daily.
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That is why I sold you the barrel. I can't make up my mind. I have even felt sorry for selling the barrel a few times. Right now if I were you I would build a 284 win. This is what the 2007 Aussy team is using for 1000 yard competions.
 
1000 yard calibers

Hi Jerry:

"As to your orig question, any new front release D mag Savage is center feed. I am waiting for some enterprising company to start making larger cap mags and this platform will pretty much take over the Rem in any mag feed game. And that will include LE and Mil applications...."

You got me thinking with your center feed stuff. I apologize for being ignorant.

A friend shooter owns a Blaser R93 LRS2 in 6mmBR and it's the smoothest rifle I ever tried. It has a 5 rds center feed detach. mag. system as you described. Gun is scoped with a NF 8-32 NXS. He's pushing the 105 Amax at 2830 fps. We were trying it at 560 yds the other day and with this low recoil set-up we could see the bullets hitting the white target. It is very accurate but not a n F-Class rig (obviously)

http://www.sigarms.com/Products/ShowCatalogProductDetails.aspx?categoryid=31&productid=66

I can see a rig like this with a cartridge like a 243 AI. Sig makes the LRS2 in 308. Something to think about.

Thanks for lining me up with this center feed mag system and it’s advantages.
I saw George Gardner from GAP at the TAC-PRO match (Mingus, TX) last year and found out he’s using the 243 AI rnd. He’s doing quite well (top 5s normaly) Of course he has and advantage on me. He’s got a gunshop ! :)

Sorry to butt in on your F-class discussions but I thought I could learn something useful from you guys.:D

Good Shooting.

Serge

PS: any more good tips would be greatly apreciated. I'm cooking up another question for you but it might take a while. I'de like to make sure it will be an intelligent one.
 
6mm Shooter said:
Right now if I were you I would build a 284 win. This is what the 2007 Aussy team is using for 1000 yard competions.
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The .284 win doesn't strike me as a typical long distance cartridge. What would be some benefits of using the .284 over a 280AI?? Less powder, recoil, barrel burn I suppose?
 
kell2784 said:
The .284 win doesn't strike me as a typical long distance cartridge. What would be some benefits of using the .284 over a 280AI?? Less powder, recoil, barrel burn I suppose?
Click to expand...

For the same reasons you'd use a 6.5-.284 .
 
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