6.5 Swede vs Creedmoor?

[taliv]

Even the most casual comparison of ballistics tables for 308win and 6.5 anything will show a tremendous advantage for the 6.5 over the 308win. They don’t call them cheater cartridges for nothing. Sure hornady did a great job marketing the 6.5creedmoor, but the 260rem, 6.5x47L, and 6.5swede along with a dozen other 6.5 and 6 mm cartridges will flat smoke the 308win. That’s why in both fclass and PRS style matches the 308 shoots in its own class. It can’t compete because of math, not marketing.


The 6.5swede is an excellent choice. However you might consider a compromise.... the 6.5swedemoor
A gunsmith who does business under the name Accuracy Addiction has a good Reamer and calls it the 6.5 Addiction, but everyone else calls it the swedemoor. Of course, you’ll have to reload your own Ammo.

The problem with both the 6.5swede and the 260rem is you can’t quite hit the optimal seating depth and still fit in an AICS style magazine. Since you’re rebarreling a Mauser, you won’t have this issue. Assuming you reload, you should be able to pick a bullet and have a gunsmith sort out the proper twist rate and throat for you.
Then the only real problem is putting $800 worth of gunsmithing into a gun that will immediately be worth a fraction of that. As long as you don’t need to sell it in the future, no prob

[Bimmer]

Even the most casual comparison of ballistics tables for 308win and 6.5 anything will show a tremendous advantage for the 6.5 over the 308win... It can’t compete because of math, not marketing.

I'm not arguing whether the 6.5 has better ballistics than .308: clearly it does.

The point that UtahJeep and I were making is that the 6.5 Creedmoor's better ballistics are moot for most shooters most of the time (or even, most shooters all the time, and all shooters most of the time).

It reminds me of those guys who buy heavy duty pick-ups... to go shopping at Costco.

[Bret]

The problem with both the 6.5swede and the 260rem is you can’t quite hit the optimal seating depth and still fit in an AICS style magazine.

The 6.5Swede I get, but the 260 Remington and 6.5 Creedmore have the same COL. Sure you have to seat the same bullet a litter deeper in the 260 Remington, but that's only because the shoulder is a little further forward.

[taliv]

The 6.5Swede I get, but the 260 Remington and 6.5 Creedmore have the same COL. Sure you have to seat the same bullet a litter deeper in the 260 Remington, but that's only because the shoulder is a little further forward.

sure, but that's important. look at the 260 (left) vs 6.5cm (right)
and then a berger hybrid



now years ago, when i was shooting 260rem, i was using berger VLD which only have a .424 bearing surface, and a longer tail, despite being very close on overall length of bullet, at 1.387. If i wanted to seat the bullet where the bearing surface/boat tail junction of the bullet was at the neck/shoulder junction of the brass, the OAL of the cartridge would be 2.9305, which won't fit in the mag. I have to seat the bullet deeper (taking up case capacity). And that's with the longer tail already taking up some capacity.

the 6.5cm by comparison, with the vld is 2.790" which leaves 90 thou of room in the mag, so if one were so inclined, they could seat the bullet out farther to chase lands or whatever. and when the hybrid came out, with it's shorter tail and longer bearing surface, it gives you even more room to play with seating depth.

2.880" max OAL for AICS magazine
260rem case length 2.035 neck length .2595
6.5cm case length 1.920


don't get me wrong. 260rem is a great cartridge. it was just designed for lighter bullets. it has a short neck, and long shoulder, which isn't great and contributes to having to trim brass more between firings. if you look at the popular benchrest cartridges, they have steep shoulders and long necks for accuracy and efficiency. the CM shoulder and neck are a good compromise for accuracy and reliable feeding in a gas gun.

[gaijin]

Great info/insight Taliv.

[Bret]

now years ago, when i was shooting 260rem, i was using berger VLD which only have a .424 bearing surface, and a longer tail, despite being very close on overall length of bullet, at 1.387. If i wanted to seat the bullet where the bearing surface/boat tail junction of the bullet was at the neck/shoulder junction of the brass, the OAL of the cartridge would be 2.9305, which won't fit in the mag. I have to seat the bullet deeper (taking up case capacity). And that's with the longer tail already taking up some capacity.

the 6.5cm by comparison, with the vld is 2.790" which leaves 90 thou of room in the mag, so if one were so inclined, they could seat the bullet out farther to chase lands or whatever. and when the hybrid came out, with it's shorter tail and longer bearing surface, it gives you even more room to play with seating depth.

2.880" max OAL for AICS magazine
260rem case length 2.035 neck length .2595
6.5cm case length 1.920

From what you're saying it seems to me that the advantage of the 6.5CM is that the case is shorter which allows for a longer bullet outside of the case mouth. It just seems odd to me that a shorter case with less capacity would have an advantage.

don't get me wrong. 260rem is a great cartridge. it was just designed for lighter bullets. it has a short neck, and long shoulder, which isn't great and contributes to having to trim brass more between firings. if you look at the popular benchrest cartridges, they have steep shoulders and long necks for accuracy and efficiency. the CM shoulder and neck are a good compromise for accuracy and reliable feeding in a gas gun.

I definitely understand that the sharper shoulder and longer neck would be advantageous all else being equal.

[1168]

Since we’re on the topic, something (hypothetical) that has always confused me: wouldn’t a 260 still have more case capacity than a 6.5 CM with the longer bullet intruding, assuming both are seated to the same OAL? I get the part about the case geometry being less well-suited to the longer bullets, and some may not work at all, but capacity should still be more with the 260, correct?

[grizzman]

I also expected a .260 Rem case to have slightly more capacity than the 6.5 Creedmoor, but I appear to have been wrong.

According to QuickLOAD, 44.7 grains of Reloder 19 fills the .260 Rem case to 105% capacity, with a 140 grain ELD-M loaded to 2.850" OAL. The chamber pressure is 59,614 psi at 2816 fps.

The same amount of powder, same bullet, and same OAL for the 6.5 Creedmoor results in the case being 101.6% full. The chamber pressure is 55,816 psi, with a resulting (estimated) velocity of 2776 fps.

[taliv]

https://www.chuckhawks.com/case_capacity_matters.html

Chucky says 260 holds a full grain more water than 6.5cm so you’re right. However the tail of the bullet back in the case also matters. What is it the cool kids say these days? People don’t think shoulder angle be like it is, but it do.

[taliv]

From what you're saying it seems to me that the advantage of the 6.5CM is that the case is shorter which allows for a longer bullet outside of the case mouth. It just seems odd to me that a shorter case with less capacity would have an advantage.

Yep that’s what I’m saying (shorter case, longer neck). If that seems odd check out what cartridges hold all the 1000 yard benchrest records. They’re prob all based on 6BR cases. I doubt you’ll find a magnum in the bunch.