6XC vs. 6.5 Creedmoor

[orkan]

I'm looking at building a new rifle. I want low recoil and impressive ballistics. I've narrowed my choices down to 2 cartridges.

6XC which will launch a 115gr DTAC with a G1 BC of .585 at about 3000-3050fps.

6.5 Creedmoor which will launch a 140gr Amax with a G1 BC of .550 at about 2850fps.

Both will run from short action DBM's.
Both offer superior ballistic performance with the edge going to the 6XC.
Both will run best in a 26" or longer tube.

On one hand, I'm drawn to the 6XC, but the DTAC is really the only bullet I'd want to shoot... and I have no idea how they behave on game. I want to be able to get good terminal performance on flesh as well as be able to punch steel way out there. I know that the 140 Amax will be lethal.

On one hand, I'm drawn to the 6.5 creedmoor because of availability of brass... but then several companies are making 6XC brass now as well.

I'm wondering if any of you have personal experience with both, or each cartridge individually? Any drawbacks that would push you toward one over the other?

[Todd.K]

Hornady updated the BC of the 140 Amax
http://www.hornady.com/store/6.5mm-.264-140-gr-A-MAX/

and the DTAC BC is the high velocity not the average as I recall.

If brass availability is a concern then the 260 should be on your list as well.

[orkan]

Brass availability isn't really a concern, as all seem to be available now. I looked at the 260, and it just seems that the creedmoor is a more efficient and easier to deal with cartridge.

So, given the 140 amax near-equal BC... that makes me feel a little better about going that route.

However the velocity difference seems vast. Are my expectations not correct on the velocity? From what I'm reading on the 6XC, they can push the DTAC at 3050 pretty easily. From what I'm seeing on the creedmoor it tops out around 2900. That would still give the ballistic advantage to the 6XC even with similar BC's.

Do you shoot either cartridge?

[dieselgeek]

I shoot 6.5CM and really like it. I know you reload a lot, but I just buy mine factory and they still group under 1/2 min. I've not chronoed mine, but my dope is consistent w/ 2800 fps. I'm running a 25 inch hart barrel on a trued 700 action. I've got around 600 rounds down it so far. Barrel life is much longer w/ the CM vs the XC

[orkan]

Barrel life is much longer w/ the CM vs the XC

Why?

With velocities shoulder angles, neck lengths, and powder charges being around about the same... I wouldn't think there would be a noticeable difference between the two.

What kind of round counts are you seeing before accuracy drops off and a new tube is required?

I view barrels as wear items anyway... but this stuff is always good to know.

[Todd.K]

I have a 260, but I mainly shoot the 95gr Vmax at varmints.

I think the 6.5 has slightly less volume and runs slightly higher pressure than the 260 so they end up too close to call.

I'd be careful comparing real loading data or ammo that was pressure tested to a wildcat "safe" handloads.

[orkan]

I'd be careful comparing real loading data or ammo that was pressure tested to a wildcat "safe" handloads.

I don't follow you on this.

[dieselgeek]

Why?

With velocities shoulder angles, neck lengths, and powder charges being around about the same... I wouldn't think there would be a noticeable difference between the two.

What kind of round counts are you seeing before accuracy drops off and a new tube is required?

I view barrels as wear items anyway... but this stuff is always good to know.

For some reason I was thinking the 6XC was a 1500 round barrel. I guess I was wrong.

[Todd.K]

Comparing factory loads or reloading data made with a pressure test barrel to handloads with unknown pressure is not apples to apples.

[orkan]

Comparing factory loads or reloading data made with a pressure test barrel to handloads with unknown pressure is not apples to apples.

Yeah... I realize that. I was drawing my data from what people are seeing in the real world and reporting on various forums, and averaging it. Got the data via google, in other words.

If my velocity estimates for each cartridge are off... then tell me what you've personally experienced. That is what I'm after, hence the reason for this thread.