Stag-10 in 6.5 Creedmoor or 260 Rem?

[mmattockx]

I haven't really been watching the NR sweepstakes lately, mostly shooting at the range with both handguns and short barreled rifles so NR status is no issue for me, but some of the new offerings are pretty tasty. I am now thinking that a Stag-10 in one of the above 6.5mm cartridges might make my ideal anti-fudd hunting rifle.

Can anyone explain why someone would choose 6.5CM over 260 Rem for a hunting rifle in an action that will easily handle either one? I favour 260 Rem for the extra case capacity to handle the 140gr bullets but can be convinced otherwise if there are some good reasons. I will reload for either and currently don't shoot either, so the investment in terms of dies and brass will be the same. I currently hunt with 6.5x55 a lot of the time and really like the 6.5mm caliber.

Either way I will probably buy a receiver set and roll my own, so the availability of complete rifles doesn't matter much to me. I'm also in no hurry, this would be for next year not this fall.


Thanks,
Mark

 

[bryan.14]

I've wondered the same thing.... Perhaps barely less recoil?

 

[rugbydave]

The advantage of 6.5 Creedmoor over a .260 is that the cartridge is designed such that you can seat the bullet further out of the case for a given max OAL. That lets you keep the ogive closer closer to the lands and also means that the bullet isn't pushed back into the case, lowering your case capacity. The 6.5 Creed was designed to basically have the same performance as a .260 while better fitting in an AICS mag. Same will hold true for the even shorter OAL of Pmags and the like (2.800" or so).

 

[mmattockx]

I've wondered the same thing.... Perhaps barely less recoil?

All of the 6.5's have such moderate recoil that it wouldn't matter, they are pussy cats to shoot.

The advantage of 6.5 Creedmoor over a .260 is that the cartridge is designed such that you can seat the bullet further out of the case for a given max OAL. That lets you keep the ogive closer closer to the lands and also means that the bullet isn't pushed back into the case, lowering your case capacity. The 6.5 Creed was designed to basically have the same performance as a .260 while better fitting in an AICS mag. Same will hold true for the even shorter OAL of Pmags and the like (2.800" or so).

OK, I went and did more looking at the two. The 6.5CM only has 2% less case capacity than the 260, which is negligible. Especially as the 260 suffers from having to seat bullets deep to make the OAL, as you note. It shouldn't make much different on getting the ogive close to the lands, as the reamer determines that distance and the throat can be cut to suit. The CM also runs slightly higher max pressures which should equal out the two pretty well. I thought there was more difference between them, but it looks like they are very much equal in performance while the CM is more suited to running in an AR-10 style semi. That makes the choice easier, thanks for the info rugbydave.


Mark

 

[Maple57]

Old school case geometry was long and with soft shoulder angles.

New school prefers shorter cases with sharper shoulder angles and there are subtle advantages to this.

First is throat erosion... A soft shoulder angle is known to generate earlier throat erosion because of the way gas fires out of the case directly onto the rifling. Sharper shoulder angles redirect the flow of hot material onto the inside of the case mouth and this helps protect the barrel.

It also affects back pressure within the case itself and affects how consistently the powder burns. If the powder migrates forward early it does not burn as consistently and velocity with low SDs are harder to maintain.

Next on the roster is case growth after firing. If you are not a hand loader this point is irrelevant, but if you are its important.

Cases with a sharper shoulder angle do not need to be length trimmed as often so it's certainly more convenient and the case weight remains more constant over the life of the case.

This is subtle stuff and the difference between one and the other is not going to make the difference as to whether or not you would win a rifle match because you picked a 260 over the 6.5 Creed.

The other story might be the direction the market is taking as even the military is starting to use the 6.5 Creed. It's gaining in popularity and for good reason so there is long term safety in knowing you'll have no trouble finding ammunition both in the short term and long term future.

 

[mytiburon]

When i researched the two myself I found the REM 260 could be pushed faster beyond 800 yards and also has the advantage of being easier to form/make 260 brass from the other 308 family of brass. RCBS makes 260 rem small base dies for "AR" type rifles and you DO need small base if you have a quality auto loading rifle with a tight chamber.

 

[rugbydave]

All of the 6.5's have such moderate recoil that it wouldn't matter, they are pussy cats to shoot.




OK, I went and did more looking at the two. The 6.5CM only has 2% less case capacity than the 260, which is negligible. Especially as the 260 suffers from having to seat bullets deep to make the OAL, as you note. It shouldn't make much different on getting the ogive close to the lands, as the reamer determines that distance and the throat can be cut to suit. The CM also runs slightly higher max pressures which should equal out the two pretty well. I thought there was more difference between them, but it looks like they are very much equal in performance while the CM is more suited to running in an AR-10 style semi. That makes the choice easier, thanks for the info rugbydave.


Mark

My pleasure! What I meant by being closer to the lands was more than it's easier/more feasible to chase the lands as your throat erodes with a shorter OAL. In any case, probably not something you (or I) will do in a semi anyways. Good luck on your build, I'm planning a 6.5 Stag 10 as well.