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260 vs 6.5 SLR

lencomatt

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Jul 19, 2009
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Anybody played with a 6.5 SLR and a 260? I have a 6.5mm barrel and was going to do a 260, but after reading a little about the 6.5SLR it sounded a little more interesting to me. They say its worth about 100fps over the 260 I was wondering if that was true. My buddy has a 6 Competition Match, a 243 with a 30 degree shoulder and loves it and that what had me looking into the SLR, it sounds like the 6.5mm version of that.
 
I have an SLR reamer ordered, but haven't fired the cartridge yet.

That said, changing the shoulder angle isn't going to net you 100fps from an otherwise identical cartridge. Case capacity is essentially identical between the two, so you're not going to find a different (magic) powder that makes use of the different/smaller case capacity to such an extent you see a significant velocity gain...especially at equal pressures with equal barrel length.

There are reasons to choose the SLR over a standard 260, but higher velocity isn't one of them.

Who suggested/claimed the 100fps advantage you cited?

What was their barrel length?
 
I would NOT say that you will get a 100fps increase in velocity from the SLR. Case capacity is about 1 grain less. Mine shoots great at 2820-2840...load dependent with 4350..
 
MTETM, what barrel length and maker if you dont mind. Thinking about going this way once my 260 is toast I am at 2830 with 140 Amax in a 24" obermeyer with H4350
 
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lencomatt,

I would agree with MTETM, 6.5 Super SLR is a about a better case design, with a longer neck, 20 degree shoulder and better throat/barrel life.

My dies, reamer and gauges have just turned up and I will now need to give some thought to a barrel.

Another advantage of the design is one pass of case through a FLS die and presto, 6.5 Super LR.

Regards,
SH
 
The SLR's seem badass. I plan to go to 6.5SLR when I decide to rebarrel/sell my .260. 30deg shoulder and long neck should promote longer barrel life and the taper of the wall of the case should reduce bolt thrust. I do not see it being any faster than a .260.

This is just my opinion.
 
Turbo54-the claim was on a forum somewhere, I didn't really believe it was just due to the case design. Maybe a slower 260 barrel to faster 6.5SLR, I don't know? That's why I was asking.
 
MTETM, what barrel length and maker if you dont mind. Thinking about going this way once my 260 is toast I am at 2830 with 140 Amax in a 24" obermeyer with H4350

Both of our barrels are 27 inch, 1:8 Benchmark's. I shoot either 142 SMK or 140 Hornady BTHP. The current load in WW brass is 43 grains. For the first 1300 rounds on my rifle, I shot 142's with 42.2 for 2820.
 
When sizing Winchester .243 brass to 6.5SLR does the shoulder being necked down increase the thickness of the neck to the point that the neck needs to be turned?
 
Not on mine...nor have I had a doughnut issue..

When sizing Winchester .243 brass to 6.5SLR does the shoulder being necked down increase the thickness of the neck to the point that the neck needs to be turned?
 
About half way down the page

6.5 Super LR

He probably saw that but wanted to hear about the experiences of people not trying to sell him something.

I haven't started shooting one yet but have formed 10-15 cases from Winchester 243 brass. The loaded necks measure ~.292 all the way down at the neck/shoulder junction, and .290-.291 everywhere else.

[MENTION=47204]BoilerUP[/MENTION]

What it provides over 6.5cm is a smidge more case capacity and readily available, inexpensive brass.
 
I haven't cronographed mine yet but I just got me 260imp 30degree back and am now just fireforming cases. I wanted to use Lapua brass is why I went with the IMP 30 degree over the SLR. I could care less what the velocity is I was happy with the plain 260 as far as that goes.

I wanted the better case design and hopefully better barrel life and accuracy. Some of the the 260s can be finicky as far as accuracy goes. I had the 6SLR and really liked it.

I had mine built as a tactical rifle with a Kreiger sendero contour at 25"s in a McMillan M40A1 stock. Its shooting groups in the 5/8" range right now with 43grs of H4350 and 123,139 lapua and 140MK, 140 Hornady match bullets. It does not seem to be picky the only load it didn't shoot well was a load with 123 Hornady AMAXs. Most of the groups have 4 in under a .5 I also shot a couple of groups at 600yds but it was in a nasty switching wind and one load with 140MKs was 4"s.

The one day I was load testing I shot a group with 4 different bullets two different powders, 3 different bullet weights and shot them at 100yds and they all went into a .960 group at 100yds. I didn't think that was to shabby!!
 
He probably saw that but wanted to hear about the experiences of people not trying to sell him something.

I haven't started shooting one yet but have formed 10-15 cases from Winchester 243 brass. The loaded necks measure ~.292 all the way down at the neck/shoulder junction, and .290-.291 everywhere else.

[MENTION=47204]BoilerUP[/MENTION]

What it provides over 6.5cm is a smidge more case capacity and readily available, inexpensive brass.

"readily available" is why I am interested.

turbo54, I see 243 brass talked about, wonder if the 7mm08 brass would work as well. It seems to work for my 260... when it can be found :(
 
"readily available" is why I am interested.

turbo54, I see 243 brass talked about, wonder if the 7mm08 brass would work as well. It seems to work for my 260... when it can be found :(

I hear ya. Even in non-crazy times, I just don't like being beholden to a single source for brass. Even with Nosler now offering it at $1+/piece, I still consider it "single source" brass. I started shooting 284Win last year and quickly found necked up Lapua 6.5-284 to be both expensive and frustrating on several levels. First it seriously sucks to have a "tactical match rifle" that shucks out $1.50 empties off into the bushes (ESPECIALLY when you've got a CRF Win70 that can launch them into the troposphere, and your partner is running your rifle). Secondly, the Lapua requires serious prepwork to avoid getting the donut.

My point is that I basically have to use WW Super brass, which is "single source". Making things worse, Winchester only makes 284 brass ocassionally, as they see fit. What they see as "fit" and what I see as "fit" are apparently two very different things.

I love the chambering, but it is not without its issues.

Back on topic:

The 6.5SLR isn't going to do work any miracles over a 6.5creed or a 260, but it provides a few niceties.

In regard to using 708 brass, I think it'll be fine, particularly if you load it at 2.885" or more, where only the boat tail of most high BC 6.5mm bullets is below the NSJ of the case.

It's a nice looking cartridge!
 
The 7MM-08 brass will work fine. I used it for my 260 and the loaded neck diameter was smaller than my necked down 308 Lapua brass that I had neck turned. I am thinking the neck thickness is only around .015 or less. I always neck turn all my brass if its only to "Clean" up the necks so they are all the same thickness. The Winchester brass with the thiner necks should not create any problems for you. The easiest way to tell would be to form a couple of them and then test fire them in your rifle. Then take the fired case and see if a bullet will slide into the fired case without having to force it. If it goes in easy then your fine. If not then your necks are to thick. Hope this helps answer your question.
 
He probably saw that but wanted to hear about the experiences of people not trying to sell him something.

I haven't started shooting one yet but have formed 10-15 cases from Winchester 243 brass. The loaded necks measure ~.292 all the way down at the neck/shoulder junction, and .290-.291 everywhere else.

[MENTION=47204]BoilerUP[/MENTION]

What it provides over 6.5cm is a smidge more case capacity and readily available, inexpensive brass.

Correct. I wanted to hear from someone who has no vested interest in the cartridge who could provide real world numbers.
 
Here are a couple pictures:

First is winchester 243 that was lubed then passed in/out of the SLR die, bullet seated, then buffed with scotchbrite.



Next is a 243 case necked up to 6.5mm, a 6.5 SLR dummy cartridge, and another SLR-formed case necked up to 7mm and a 162amax seated. Again, no fire forming or anything fancy.

 
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As an aside, I understand that Robert wanted to avoid fireforming being required for this cartridge, and that makes good sense...

But anyone that is OK with fireforming should consider "improving" this cartridge by changing the body taper to 6.5CM (ish) specs. The x-08 cartridges have ~.010" of taper per inch, and the CM has ~.0055"/inch. Without crunching the numbers, I'd expect one could gain several grains of case capacity doing so, if they're willing to FF the brass.
 
Exactly what we all needed... another 6.5mm caliber cartridge based on the 308. Because 6.5 cm, 260 Rem, and 6.5X47mm Lapua just wasn't enough. This remind me of when they were trying to come up with odd case sizes for beer in the early 90's. They were marketing 20 packs and 18 packs because 6, 12, and 24 were so 1980's. The beer tasted the same.
 
Exactly what we all needed... another 6.5mm caliber cartridge based on the 308. Because 6.5 cm, 260 Rem, and 6.5X47mm Lapua just wasn't enough. This remind me of when they were trying to come up with odd case sizes for beer in the early 90's. They were marketing 20 packs and 18 packs because 6, 12, and 24 were so 1980's. The beer tasted the same.


I knew .260 brass could be made from .308 but the neck has to be turned. You might be on to something. What is the process for making 6.5CM and 6.5x47L from the .308 case. The process sounds pretty labor intensive but if someone with a 6.5CM or 6.5x47 is really hurting they could make their brass from the plentiful .308 case!
 
Exactly what we all needed... another 6.5mm caliber cartridge based on the 308. Because 6.5 cm, 260 Rem, and 6.5X47mm Lapua just wasn't enough. This remind me of when they were trying to come up with odd case sizes for beer in the early 90's. They were marketing 20 packs and 18 packs because 6, 12, and 24 were so 1980's. The beer tasted the same.

While I agree with you for the most part, your same argument could be used for the 243, 6xc, 6x47L, 6CM, 6Creed, 6Rem, 6SLR, etc...

there are nuances. There are differences. It's not as simple as X grains of powder and Y bore size.

Yes, there is a lot of overlap, but they're not all just the same shit. Similar shit, sure...
 
I agree with turbo54. There are differences and they are mostly to improve barrel life and accuracy so what is not to like about them?? Fireforming the new brass isn't like the old days when you shot a round that was not up to par with the new case. My 260imp 30 degree is the same as shooting a 260 when I fireform the brass and its probably as accurate as the new case will be so I don't loose anything in the forming process. I bellieve it is the same with the 6.5SLR too I know it was that way with my 6SLR. I actually shot some of my best groups fireforming
 
While I agree with you for the most part, your same argument could be used for the 243, 6xc, 6x47L, 6CM, 6Creed, 6Rem, 6SLR, etc...

there are nuances. There are differences. It's not as simple as X grains of powder and Y bore size.

Yes, there is a lot of overlap, but they're not all just the same shit. Similar shit, sure...

I would make the same argument for 243, 6xc, 6x47L, 6CM, 6Creed, 6Rem, 6SLR. Of those, 243 and 6xc are in wide use with the difference being that 6xc has less velocity and more barrel life, which is a huge deficiency of the 243. Those others are also rans. The difference between the 6.5-08 and its variants is that no one has ever standardized around the 6.5 like they have for the 243. The 243 is pretty much considered the 6mm version of the 308. The others (even the 6xc) are wildcats. Every time you think we have standardized around the 6.5, someone makes a move. This is like Blu Ray vs HD DVD over a much longer time frame. Introducing another cartridge kind of muddies up the waters. For a while, I thought that the 260 Rem would be the standard. That hasn't happened yet. Enter another 6.5mm.

It sounds silly, but choose any chambering and you might have issues finding ammo and/or dies and brass for it. The fact that there is not a standard at this point seems to be the reason for having the 6.5 SLR... so you can find the right brass (you will never find match ammo for it, though).