6.5*51L - "improved" 260.

[camac]

I am in a real phase of my life of experimenting (more time I suppose) but am about to convert a 6.5*47L into a 6.5*51 by sending the reamer in deeper effectively creating a 260 improved type case. I know there are 260's and other 260 improved versions but I have the reamers and other reloading equipment to do this one and thought it would be interesting. We are going to do 2 as a friend has a 6.5*47L and cannot get the velocity from it he was hoping without pushing the pressure - so we thought a bit more boiler room would be nice. (May do a 6.5*49 for him though)

I have no doubt that someone out there has already done this so if anyone knows where please let me know.

Brass choice will be great with Lapua making both small and large primer/flashole options in 308.

I will make our own FL dies and seating die sleeves but for those interested I think standard 6.5*47 dies could be used. Certainly the seating and neck sizing dies. Occasionally the base may need bumping in though. If a 308 FL die is used then it may knock the shoulder in a few thou too far but still should work by putting back through the 6.5*47 bump or FL die.

Any comments appreciated
Cam

 

[TonyR]

Cam.
You might want to look at some of the discussion about the 6mmBRX. It seems to use existing 6mmBR dies to size the neck and shoulder, and if I recall correctly, a small base 308 die to do the case heads. Sounds like you are thinking of something similar.

 

[camac]

Thanks Tony. Yes, I have actually already made a 6*47L with my 6BR reamers sent deaper and use the seating die and sizing dies as you mention (Then made a custom FL die). It was the success of this first trial that mad me think of this one. I also formed some brass from 308 in the 6*47 but kept thinking how easy it would be to go to 6.5 or 7mm and full 308 length as I did it.

Cheers Tony and thanks again for all your valued input - keep it coming.
ps 284 Shehane Reamers are on the way with die blanks so I will be putting that together after this one.

 

[2644ever]

Cam. I tried this kind of experiment some years ago but it was the other way around (a 6.5x51 Improved long neck, that was short chambered to accomodate the .250 Sav and the .300 Sav cases) and I ended up with the 6.5x47 L and the Creed about 10 years ago... ;D Because of the larger shoulder diameter, I found it very convenient to use a .444 marlin sizer as a body die and incidentally as a decapping die too. Just my 2 cent contribution. Have fun and long live the six five.

 

[camac]

Great feedback thanks 264forever. I never thought of the 444 dies (don't know why as I have some in the cupboard somewhere).
Cheers

 

[TiGuy]

This sounds very much like the 6.5 creedmoor doesn't it? I have never measured the case capacity but I think its about 49. Has the AI shoulder too.

 

[15Tango]

A 260 Improved would have a pretty good edge case capacity wise over a 6.5 Creedmoor. I bet the 260 Improved can deliver some impressive velocities, it's probably more accurate than a straight 260 too.

Wayne

 

[Rtheurer]

"Occasionally the base may need bumping in though. If a 308 FL die is used then it may knock the shoulder in a few thou too far but still should work by putting back through the 6.5*47 bump or FL die."

I had to do the same on another project. I used a 30'06 for the ocasional base squeeze. 270 should work too or any thing based off the 06. It wont touch your shoulder.

good luck.

RussT

 

[camac]

This sounds very much like the 6.5 creedmoor doesn't it? I have never measured the case capacity but I think its about 49. Has the AI shoulder too.

Yeah I think, the case capacity will be just slightly more than Creedmore (53 gr water capcity) but in same ball park (40 thou longer at shoulder and 80 odd at mouth). But I get to use Lapua brass and all my reamers and dies. As Wayne said I too am hoping it will perform pretty well both in velocity and accuracy stakes. I like the creedmore too. A creedmore reamer sent a little deeper (to 51mm or 308/260 length) would also be very good - maybe even better.

Russ - thanks on the 06 dies I have a 270 FL die here also so will try that when I get it going along with the 444 marlin die.
Cheers.

 

[15Tango]

Cam,

I'd almost prefer running a Creedmoor reamer deeper given the choice. I have a Creedmoor and it's always made me wonder what another 2-4 grains capacity would do with that cartridge. It would basically be a 260 AI at that point though.

You can't go wrong using the 6.5X47 or the Creedmoor as a starting point for a cartridge, they're both ridiculously accurate.

Wayne

P.S. I use Lapua brass in my Creedmoor, it's phenomenal. 8)

 

[2644ever]

RussT, with all due respect, I beg to differ: The .270 die has too much taper, it will touch the .460+ shoulder of any 6.5-.260 Imp and barely miss, in the best scenario, the Creed's shoulder.

 

[camac]

Wayne, I agree. I think I would run the creedmore reamer deeper too if I had one. However I don't have one and as I buy them in pairs (sizing reamer and chamber reamer) it is another $276 plus freight.

The good thing is I get the odd request for 6.5*47 and Creedmore and 260 chamberings - not enough to make it worthwhile buying reamers. With one reamer you can almost have the equivalent of all three. If it works I am sure most customers wouldn't mind, especially if they get custom dies with the deal and see how easy it is to form brass from the Lapua (or other) 308 - one thing that is in abundance here.

The other good thing about the longer neck of the Lapua chambering is it allows you to design your reamer to take full advantage of a larger range of bullets. By having throat set to seat 142's down to just above the donut - The 123's and even lighter can still have enough bullet in the neck and touch the lands. Others say the longer neck may save a little barrel burn. For me I will just have to accept this is an acceptable trade for the loss of capacity against a creedmore long or other improved. As you say, either/all should be an accurate round and great.

RussT and 2644ever, The 6.5*47L front on the reamer is .2563 (creedmore .2590) and is the width of the 308 at the corresponding point on the shell for length. When sent in deeper this will be slightly wider than the 308. The 30-06 is .4409 at shoulder and I now agree with 2644 - basically will be very slightly too narrow at the shoulder for both these in extended mode. They would work for 47 in normal I think - thanks for the suggestion though - still great input and gets me looking at all the alternatives.
Cam

 

[limbic]

I've been trying the small primer 308 brass. It has been less than impressive. I turned the necks and trying to get them consistent has been a real pain the the behind. I'm going back to my 243 necked up brass and try some nosler 260 brass.

 

[camac]

Limbic, Have you tried the magnum primers and/or opening up the flasholes a little? I ask this as I am curious too. I recently built a 6*47 and a lot of comments were coming back about it on the same line. I built some large rifle brass (from Lap308) and used some original small rifle. The small rifle, small flashole seems to work on that cartridge as long as you have a fast enough powder or are driving it with a hot primer or enlarged flashole. I ended up getting good results from both magnum primers and large rifle brass. A 260 driven by small flashole is another step up the "magnum" scale.
I am guessing there is little advantage in going to small rifle primers for these cartridges (especially in cool weather) but will nonetheless try the experiment. German Salazar has done some work on this too. At least with the 308 you can go to a faster powder.

 

[Chuckw]

CAMAC,

i already did this a reported the results here. i think the post was named 6.5x4... something. i did just what you are talking about. other than have to build form dies, it was an awsome project. i actually rechambered the barrel to .260AI and it will not make as much velocity and the accuracy is not as good as it used to be.

chuck

 

[camac]

Chuck,
Thanks. I thought someone would have already done it. Nice. Can you point me to the post. I can't find it but will keep looking.
Cheers

 

[Pendragon]

CAMAC,

It depends upon what you want to accomplish as to which way you might want to go.

If you are trying to maximize case capacity, the AI is probably the way to go.

If, on the other hand, you are trying to make a case off of the 243/260 case for other reasons I would think what you have in mind is close to what I have looked at.

One of the benefits of the 6.5x47 Lapua case is that the bottom of the bearing surface of the bullet remains above the neck/should junction. When seating bullets in a 260 Rem case I frequently feel a difference in seating pressure when the base of the bullet's bearing surface gets to the neck/should junction which I have yet to experience with the 6.5x47 Lapua. (My 6.5-08/260 Rem chambers are short throated to be able to either touch or come close to the lands when seated to Rem 700 short action magazine length...about 2.820" OAL.)

If you either switch to a long action or have the magazine opening in a short action opened up to take a Wyatt magazine (roughly 0.110" longer) some of these problems can be minimized.

I ran some comparisons a few years ago, but did not proceed with the project, for a 260 Rem with a 35º shoulder that begins at the "normal" shoulder/body junction and results in a longer neck. Basically, the 139 gr Scenars and 142 gr MKs could be seated to a length appropriate to my chamber and not push the bottom of the bearing surface past the neck/shoulder junction.

One other possibility is to use a 30º shoulder in the same manner, but it winds up with the bottom of the bearing surface in the problem area unless you throat the chamber longer and use the longer magazine. This is the same body as the 22-243 Middlestead with a different neck diameter. Somewhere or other I still have a Middlestead FL die that I bought for a project along these lines, but never got very far with. Brass for this case should form in a single pass through the sizing die and require no fire forming as such. Most recently, it occurred to me that it should be possible to move things back about 0.050" and just trim the FL sizing die. The result would be an easy to form case with a slightly longer neck and, I think, none of the problems of pushing the bullet too deep into the case. Most likely you could use a stock 260 Rem seater or one with very minimal modification.

If you do not intend to use a magazine, that is an entirely different matter.

I had recently looked at my 6.5x47 Lapua ammo and wondered about having a reamer made with a longer neck (to avoid having to trim cases) that would have the body shape of the 6.5x47 Lapua with the shoulder/body junction being 0.050" or so short of where shoulder/body junction is for the 260 Rem. This would have more case capacity than the 6.5x47 Lapua, but less than the 260 Remington, although I did not determine the exact amount. I believe that this case should form in one pass through the FL sizer, but I have not tried it.

I think the advantage to using the 6.5x47 Lapua body shape is the ability to use off-the-shelf dies with minimal modification which are readily available without a lengthy wait.

Dave Kiff of Pacific Tool and Gauge has a reamer design he calls a 6.5mm Rogue with a 37º shoulder which might be of interest, but I have no idea of die availability.

All in all, the 260 Remington is not that bad the way it is.

 

[camac]

Thanks Pendragon for all the input.
The "reason" for doing this is really that I have 6.5*47 reamers (resizer and FL) that are made for 123 grain bullets. There is enough room in neck to seat the 142's without getting to the donut. I have made a few different 6.5's including 6.5*284, 6.5*55 Rogue (as you mentioned), and 6.5*47. I do love the 6.5*47L but wish it just had a "bit" more boiler room (after. The thing I kept noticing when sizing down a lot of 308 brass to other calibers is how easy it is to do the neck and first bit of the shoulder (or change shoulder angle). In fact it was whilst sizing some 308 down to 6*47L recently that I got the idea. It is so easy to get to the first point. A few bumps through the FL die, trim and turn and away you go. I literally have many thousands of 308 cases too.
So the reason really was to save money on brass, reamers, dies etc whilst building a 6.5 between my 6.5*284 barrel burner and the 6.5*47 (which I would like alittle more grunt out of) - there just seems some nice things about it too
The intention is not to rinvent another 6.5 as there are so many good ones out there and this will not offer serious advantages over any of them.
But for me, some nice ones are as you mention : Longer neck so can be seated further in with 140's and can be used in Watt or Savage magazines or similar - also can use a range of bullets from 123-140 well. Longer neck theoretically might save a litlle barrel life (not 100% sure on that one though). "improved shoulder angle over 260 for all those advantages but still will feed well in magazine. I already have Brass, reamers, dies, Barrels, Bullets so no outlay. I think this cartridge will have enough boiler room to get me what I want without being the barrel burner that the 6.5*284 is (and I have done a few barrels in on that cartridge). Similarly anyone with a 6.5*47 can do the same at very little cost (They would already have the barrel, dies etc etc too.). In fact the 6.5*47 brass is so expensive ver here and I am not sure about the small flashole offering any advantages that it almost seems like the "economical" way to go.

 

[Pendragon]

CAMAC,

Given your priorities, I think I would work out the case and then seat a bullet to the desired length within the limitations of your magazine length and send it off to the reamer maker to get a separate throating reamer for your 6.5x47 Lapua reamer. I think this would be the least expensive way to accomplish what you want.

That said, I do not know what your setup is for trimming and/or neck turning. I am at the stage where I prefer to avoid both of those operations if at all possible.

Unless you get into some rather hot loads you may be able to get away without a true FL sizer for the new case. If need be you could either try the 444 sizer as suggested or get a 308 body die and cut off most of the upper part so that you could resize the bottom of the case and then use the 6.5x47 Lapua sizer for the rest of it. The alternative is to have one of the bench people make a custom sizer for you or get another sizing reamer and have it done.

There have been a variety of different cases over the years where people made a long 6mm BR shaped case on a .243 Win case which have generally worked well though with the expected short barrel life of hot rod 6mm.

Oh, the price of 6.5x47 Lapua brass...has gotten completely out of hand. Lapua could just kill it off if it keeps going up. I can see no sane reason they are charging so much more for it than .308 or .243 brass, well, unless you think they are just gouging people because they can.

I do not know the particulars of the 6.5x47 Lapua reamer used to chamber my barrel, but it will chamber a 139 Scenar factory round and my loads with the 139 Scenar seated so as to not contact the donut. The overall length is 2.770" or something thereabouts.

Cheers

 

[camac]

CAMAC,

Given your priorities, I think I would work out the case and then seat a bullet to the desired length within the limitations of your magazine length and send it off to the reamer maker to get a separate throating reamer for your 6.5x47 Lapua reamer. I think this would be the least expensive way to accomplish what you want.

That said, I do not know what your setup is for trimming and/or neck turning. I am at the stage where I prefer to avoid both of those operations if at all possible.

Unless you get into some rather hot loads you may be able to get away without a true FL sizer for the new case. If need be you could either try the 444 sizer as suggested or get a 308 body die and cut off most of the upper part so that you could resize the bottom of the case and then use the 6.5x47 Lapua sizer for the rest of it. The alternative is to have one of the bench people make a custom sizer for you or get another sizing reamer and have it done.

There have been a variety of different cases over the years where people made a long 6mm BR shaped case on a .243 Win case which have generally worked well though with the expected short barrel life of hot rod 6mm.

Oh, the price of 6.5x47 Lapua brass...has gotten completely out of hand. Lapua could just kill it off if it keeps going up. I can see no sane reason they are charging so much more for it than .308 or .243 brass, well, unless you think they are just gouging people because they can.

I do not know the particulars of the 6.5x47 Lapua reamer used to chamber my barrel, but it will chamber a 139 Scenar factory round and my loads with the 139 Scenar seated so as to not contact the donut. The overall length is 2.770" or something thereabouts.

Cheers

The 139 and 142's and 123's will all seat inside my magazine length with my current reamer (set for 123 throat length but 139 -142's all sit above the donut and I will be building 2 single shot rifles first anyway but do intend to build a repeater or two

I trim and neck turn all my chamberings. A one off job that I don't mind doing and doesn't take long. For a true hunting rifle I might not have bothered but these reamers are designed for minimum neck turn. I think lengthening the neck and bumping back the shoulder on a 308 case I would recommend neck turning though as the base of the neck can get quite thick.

I have the resizing reamer so make my own FL sizing dies anyway (use a $19.00 blank and then heat treat) but for anyone else interested I am sure the suggestions made earlier will work too.
Thanks again.
Cam