Is 308 the new .40?

Queen Bee

NES Member
Rating - 72.7%
16   6   0
Joined
May 12, 2011
Messages
3,641
Likes
2,281
Location
Hogwarts
With competitive shooters moving from 308 to 6.5 creedmore, and 223/556 being the go to cost effective caliber for rifles. Where does 308 stand now? Thinking about marksman,DMR rifles, is the 308 fading. 6.5 is readily becoming a semi auto go to DMR cartridge that can reach 1000 yards with less of a rainbow trajectory. weapons like the MK 12 mod 0 that can push a 5.56 out to 600 yards accurately and allow you to shoot more cost effectively. The 308 is the middle child between the two.

So my question, will 6.5 creed semi autos become future? I know in bolt guns that cartridge has mostly taken over in competition.
 

slap shot

NES Member
Rating - 100%
18   0   0
Joined
Mar 5, 2013
Messages
12,965
Likes
7,924
Location
NH
I think 308 is safe for a while due to the very favorable ballistics out to where most shooters shoot, cost of ammo and popularity of ar10 in 308. I have 2 6.5 cm bolts I reload for but when I build an ar10 will most likely be 308 first.

Don’t forget, CM is not the first 6.5 and the 308 is supported by military
 

Queen Bee

NES Member
Rating - 72.7%
16   6   0
Joined
May 12, 2011
Messages
3,641
Likes
2,281
Location
Hogwarts
I think 308 is safe for a while due to the very favorable ballistics out to where most shooters shoot, cost of ammo and popularity of ar10 in 308. I have 2 6.5 cm bolts I reload for but when I build an ar10 will most likely be 308 first.

Don’t forget, CM is not the first 6.5 and the 308 is supported by military
But think about it ballistically, you can have a AR10 in that same platform but a caliber than can reach out much further than 308


6.5 Creedmoor shows less bullet drop at all distances. The advantage is minimal at first—at 500 yards the 308 Winchester trajectory is still within 5 inches of the 6.5 CM round. As distance increases, the efficiency of the 6.5mm bullet takes its toll, and by 900 yards it is flying more than three feet higher than the older Winchester bullet, which is just about out of gas. By 1100 yards, .308 Win is already subsonic, while 6.5 CM still has an additional 350 yards (roughly) of effective range.

Bullet drop is relatively easy to account for, remaining fairly consistent for each rifle and loading with only minor changes occurring due to barometric pressure and a few other variables. Where 6.5 CM really shines in long distance shooting is its ability to fight wind, which is much less predictable and more difficult to compensate for. In a 10 mph crosswind, .308 Win has already been pushed six inches farther than 6.5 CM at 500 yards. At 900 yards 6.5CM’s advantage grows to 28.2 inches, about three minutes of angle (MOA) difference.


Source 6.5 Creedmoor vs. .308 Winchester [Which Is Better?]
 

slap shot

NES Member
Rating - 100%
18   0   0
Joined
Mar 5, 2013
Messages
12,965
Likes
7,924
Location
NH
But think about it ballistically, you can have a AR10 in that same platform but a caliber than can reach out much further than 308


6.5 Creedmoor shows less bullet drop at all distances. The advantage is minimal at first—at 500 yards the 308 Winchester trajectory is still within 5 inches of the 6.5 CM round. As distance increases, the efficiency of the 6.5mm bullet takes its toll, and by 900 yards it is flying more than three feet higher than the older Winchester bullet, which is just about out of gas. By 1100 yards, .308 Win is already subsonic, while 6.5 CM still has an additional 350 yards (roughly) of effective range.

Bullet drop is relatively easy to account for, remaining fairly consistent for each rifle and loading with only minor changes occurring due to barometric pressure and a few other variables. Where 6.5 CM really shines in long distance shooting is its ability to fight wind, which is much less predictable and more difficult to compensate for. In a 10 mph crosswind, .308 Win has already been pushed six inches farther than 6.5 CM at 500 yards. At 900 yards 6.5CM’s advantage grows to 28.2 inches, about three minutes of angle (MOA) difference.


Source 6.5 Creedmoor vs. .308 Winchester [Which Is Better?]
I’m a huge fan of the 6.5. I just think the price of the 308 and the ballistics out to medium range make it attractive. I think if you have an ar10 you’d be wise to get 2 uppers. At least.
 

headednorth

NES Member
Rating - 100%
17   0   0
Joined
Apr 9, 2012
Messages
14,484
Likes
15,678
I cant really see average shooters abandoning 308 en masse when so many people are shooting at 100-200 yards. The article you quoted says that the difference at 500 yards is minimal. Most people go their whole lives never shooting at that distance.
 

Queen Bee

NES Member
Rating - 72.7%
16   6   0
Joined
May 12, 2011
Messages
3,641
Likes
2,281
Location
Hogwarts
Yeh while i do not have an AR10 yet, till i move out of this state, i do think about switching out my scar 17 barrel to the 6.5 CM aftermarket barrels out there.

If i ever trade it for an AR10 i will make sure to invest in some uppers
 
Rating - 100%
1   0   0
Joined
Dec 12, 2018
Messages
4,109
Likes
6,192
Location
RI
The difference between .40S&W and .308/7.62x51 is that .308 has been with us since the early 1950s and has been adopted by the military, police, competition shooters, hunters, and everyone in between. The .40 was always a niche caliber somewhat adopted by police departments that wanted something between a 9x19 or .38/.357 and the 10mm, .41 Mag, .44 Mag, and .45ACP. The .308 also has international adoption.

Eventually, .308 will go the way of .30-06 and .45-70 and become a heritage caliber and the choice of path dependency. 7.62 NATO hasn't been a frontline, main service cartridge for us since the mid-60s and most of our allies since the 70s and 80s. However, due to the proliferance of 7.62 NATO support rifles (DMR, actual sniper rifles, machine guns), 7.62 NATO should probably still be a military and police service cartridge into probably 2030 and 2040. Even longer if there's actually a big war within a generation or two. Look at WW1: how many old, aging cartridges got continued past the war because of the raw amount of cranked out surplus? Bare minimum, .303, .30-06, 7.62x54r, 6.5 Japanese and Carcano, and 8mm Lebel. The vast amount of 7.62 NATO is going to keep the cartridge in service until something definitively, not marginally, better comes out.

.40 on the other hand lacks such support. The .40 is sort of an odd compromise that only appealed to certain police departments. It was never a military cartridge or produced in vast amounts.

A better comparison with where .308 is today is where .30-06 was in say the late 1940s and 1950s. The military still had plenty of uses for .30-06 at the time and wasn't going to get rid of it entirely soon. Thousands if not millions of new commercial .30-06 rifles have been made since the 1950s. That's where .308 is now - there's marginally better cartridges out there but due to logistics and path dependency and cost, it isn't going anywhere anytime soon.
 
Last edited:

fencer

NES Member
Rating - 100%
9   0   0
Joined
Oct 19, 2009
Messages
11,875
Likes
9,175
Location
Southeastern Mass
First of all I would like to say.. Great thread OP. I relish caliber discussions on these boards, even when they end up being "caliber wars." Simply outstanding - thank you. I really enjoy the insight of shooters with much more skill and experience than I have,

I also want to point out that I STILL love .40. Yeah, 185 grain is a little snappy, but 165 grain really isn't and if you ever get a chance, try to get your hands on some 135 grain. It's out there. And when ammo dries up .40 is usually still available

Everyone used to point out that .40 was supported by American law enforcement from Feds, to State, to local.
True, but think about 38 special. Couldn't you say the same? How many of us still shoot a ton of 38 special in our favorite 357 revolver?

6.5 Creedmore is awesome, but I don't think 308 is going anywhere. First of all, it is very effective at ranges far greater than most shooters can shoot. There are also millions of rifles chambered in 308.

Yes, the 6.5 is a little more accurate in competition and recoil is a little less, but 308 is still really manageable and crazy accurate. I think the biggest plus with the Creedmore is how much better it copes with wind.
If I was shooting competitions, would I want the 6.5? Hell yes. For shots that I would actually take, I don't know if the additional cost is worth it. I really doubt I would take a 600 yard shot at game with either round, and unless you head out west for mulies or something you are not likely to get that shot. If I did, I would want 300 win mag or 338 Lapua.

If I made my living with a rifle, or lives were on the line, sure I would want the 6.5. Am I going to buy a new Remington 700 and mothball my old one in 308? Nope.
 

Mountain

NES Member
Rating - 100%
20   0   0
Joined
Jan 6, 2013
Messages
11,892
Likes
9,536
Interesting analogy, and to some extent it could happen but not completely. 30 cal is simply such a popular caliber and the 308 is a nice mid-power round. There's a ridiculous variety of projectiles available for every purpose under the sun and rifles of all types chambered for 308. Too much momentum to go away. From the pop culture side, I don't recall 308 ever being maligned like the fo-tay has. In contrast, 6.5 CM memes are, well, just look...



Poseur ridicule aside, 6.5 CM is a really nice round and shoots great in the AR-308 platform. I built one and EFA10'd it just before all the Healy nonsense started. Easy sub half MOA shooter and sometimes sub quarter MOA with the right ammo. It's almost boring at 600 yards on torso size plates, even in some variable wind. I occasionally shoot high power with .223 80.5 ELD's for the 600 yard stage and the wind can really push those around. I don't have a scoped .308, so can't really compare that.

1000 yards is pretty challenging for me, but if I gauged the wind right I had no trouble dinging plates with the 6.5. If I was off, minimal correction would put me on and keep me on the plate. Many will tell you 1000 yards is fine for 308 but most 308 loads will go subsonic some distance before 1000. Projectiles can yaw off course or even tumble. Granby required proof that your load was still supersonic at 1000 in order to get permission to shoot at that range. Someone is going to chime in, b-b-but you CAN do it with 308! OK, expensive VLD / ELD 175's loaded hot from a 26" barrel will do it. Not hard to do that with a range of projectile weights for the 6.5 CM and there's a wide array of factory ammo that won't go subsonic before 1000 yards. 308 factory ammo not so much.

Here's a couple threads from when I was working on my AR and its 6.5 CM loads. I blame NES for motivating me to build it, as the project started with a port cover from a group buy. One big take-away for me was to use a top quality bolt, decent barrel, and an excellent trigger. The rest is just the junk that helps those parts do their job. This build was relatively low budget:
Done! Aero M5 in 6.5 Creedmoor
Reloading 6.5 Creedmoor for Gas Guns
 

Queen Bee

NES Member
Rating - 72.7%
16   6   0
Joined
May 12, 2011
Messages
3,641
Likes
2,281
Location
Hogwarts
Fencer, your welcome :) i love caliber discussion threads too.

Stockwell, Good Points made about comparing 308 to 30-06 instead of .40 Yeh sooner or later the 308 will become the new "classic 30-06".

Mountain, LOL loved the meme. ANd i would love to compare your 6.5 AR10 to the scar 17 308 so i can find out just how much different in recoil there is to the new cartridge in town. Granted i shoot mauser 8mm without issue as long as there is a recoil pad so i am not looking at this caliber for just recoil, but also an increase in shot recovery and speeding up multiple accurate shots on target for a DMR.
 

H-minus

NES Member
Rating - 100%
1   0   0
Joined
Mar 6, 2018
Messages
535
Likes
1,050
Location
Hidden bunker in NH
I like the 6.5 cm but it is doubtful I will ever have the need to fully utilize it's capabilities. I cant remember the last time I shot over 300 yards. I use 308 for hunting and plinking and 308 puts more foot pounds of energy on targets under 600 yards. That is more useful to me. I do like the lighter recoil of the 6.5 but not enough to justify paying 20-30 cents more per round.
 

Mountain

NES Member
Rating - 100%
20   0   0
Joined
Jan 6, 2013
Messages
11,892
Likes
9,536
Fencer, your welcome :) i love caliber discussion threads too.

Stockwell, Good Points made about comparing 308 to 30-06 instead of .40 Yeh sooner or later the 308 will become the new "classic 30-06".

Mountain, LOL loved the meme. ANd i would love to compare your 6.5 AR10 to the scar 17 308 so i can find out just how much different in recoil there is to the new cartridge in town. Granted i shoot mauser 8mm without issue as long as there is a recoil pad so i am not looking at this caliber for just recoil, but also an increase in shot recovery and speeding up multiple accurate shots on target for a DMR.
At the time I selected parts, I was thinking I'd try NRA F-Tacticle class and used a 20" barrel with no brake in order to meet rules. Seems like that class never took off and I'm busy with CMP matches anyway. I have a longer Criterion barrel and a brake to install. If your SCAR has a brake, the 6.5 would make a better comparison once that brake is installed. I'm a little northwest of Worcester but also get to Granby occasionally, so you are welcome to shoot it if one of those locations works.
 

mac1911

NES Member
Rating - 100%
69   0   0
Joined
Dec 26, 2008
Messages
30,357
Likes
8,181
Yeh while i do not have an AR10 yet, till i move out of this state, i do think about switching out my scar 17 barrel to the 6.5 CM aftermarket barrels out there.

If i ever trade it for an AR10 i will make sure to invest in some uppers
Do you think your going to run your scar out to 1000 yards often ?
If I knew with any certainty i would be going out to 800-1000 yards often - 6.5 would probably creep into my safe.
Its funny though how all these 100 plus year old technology/ cartridges just keep rotating through popularity.
I never thought the small cal carry pistols .380 would be as popular as they where a few years back. Honeslty they will probably push the .32 cals again.
Its all fun and based on cost and most average ranges distance 308 and 30-06 will be around a long time.
 
Last edited:

mac1911

NES Member
Rating - 100%
69   0   0
Joined
Dec 26, 2008
Messages
30,357
Likes
8,181
At the time I selected parts, I was thinking I'd try NRA F-Tacticle class and used a 20" barrel with no brake in order to meet rules. Seems like that class never took off and I'm busy with CMP matches anyway. I have a longer Criterion barrel and a brake to install. If your SCAR has a brake, the 6.5 would make a better comparison once that brake is installed. I'm a little northwest of Worcester but also get to Granby occasionally, so you are welcome to shoot it if one of those locations works.
Well no brakes must have really killed any interest....roll eyes
 

citoriguy

NES Member
Rating - 100%
29   0   0
Joined
Dec 14, 2018
Messages
2,721
Likes
2,039
Location
PRM
I’m in the midst of an AR-10 build and am starting with a .308. That said, I may build a separate 6.5CM upper just for fun. I built a 5.56/.223 and ended up building a 300AAC upper for that, so maybe I’m just that guy...
 
Rating - 100%
26   0   0
Joined
Jan 5, 2008
Messages
7,377
Likes
4,148
Location
My forest stronghold
.308 isn't going anywhere.

That said, I do wish I'd built my AR-10 for 6.5 Creedmoor. I got into .308 after shooting and reloading for my FIL's Springfield A1A National Match rifle. When I wanted my own .30 cal, I picked .308. When the barrel wears out, it'll be replaced with 6.5.
 

Mountain

NES Member
Rating - 100%
20   0   0
Joined
Jan 6, 2013
Messages
11,892
Likes
9,536
Well no brakes must have really killed any interest....roll eyes
Huh? Probably AR shooters are just terrified of backing their smack talk with a scored target. LOL, you know there's some truth in that. Also, I think many who might have been interested in using an AR-type rifle in F-class probably lost interest when PRS began taking off. And yeah, PRS recommends brakes.
 

citoriguy

NES Member
Rating - 100%
29   0   0
Joined
Dec 14, 2018
Messages
2,721
Likes
2,039
Location
PRM
can you use 6.5 cartridges in an AR10 .308/7.62 mag?
Different barrels. Like 300AAC and 5.56/.223.

EDIT - you asked about mags. I don’t know the answer to that. Hopefully someone else can chime in with that answer.
 
Last edited:
Rating - 0%
0   0   0
Joined
May 23, 2013
Messages
3,798
Likes
2,035
Location
I hate this f***ing state.
I cant really see average shooters abandoning 308 en masse when so many people are shooting at 100-200 yards. The article you quoted says that the difference at 500 yards is minimal. Most people go their whole lives never shooting at that distance.
This.

Although I'm hoping QB is correct, it'll just bring down the prices for .308 and(like in the Obama panics) I'll never be bothered with limits while everyone else is running all over buying 1 or 2 boxes of 9/5.56 and hopefully 6.5cm at a time. [laugh]
 

drgrant

Moderator
NES Member
Rating - 100%
61   0   0
Joined
Mar 21, 2006
Messages
72,700
Likes
37,241
With competitive shooters moving from 308 to 6.5 creedmore, and 223/556 being the go to cost effective caliber for rifles. Where does 308 stand now? Thinking about marksman,DMR rifles, is the 308 fading. 6.5 is readily becoming a semi auto go to DMR cartridge that can reach 1000 yards with less of a rainbow trajectory. weapons like the MK 12 mod 0 that can push a 5.56 out to 600 yards accurately and allow you to shoot more cost effectively. The 308 is the middle child between the two.

So my question, will 6.5 creed semi autos become future? I know in bolt guns that cartridge has mostly taken over in competition.
6.5 Kardashian is still pretty rare. Not going to displace 308 anytime soon, particularly given the cost difference and # of 308 guns floating around.


-Mike
 

mac1911

NES Member
Rating - 100%
69   0   0
Joined
Dec 26, 2008
Messages
30,357
Likes
8,181
Huh? Probably AR shooters are just terrified of backing their smack talk with a scored target. LOL, you know there's some truth in that. Also, I think many who might have been interested in using an AR-type rifle in F-class probably lost interest when PRS began taking off. And yeah, PRS recommends brakes.
Come on you want people to shoot with out a muzzle device.... I think what happened with F class is just to middle of the road and at first it was 556/308 only IIRC. Anyhow been trying to do a little PRS type matches even at 200 yards theres very little interest around here. Most people just want to shoot at 18"x16" torso size steel and scream HIT
 

Cuz

NES Member
Rating - 100%
7   0   0
Joined
Apr 12, 2006
Messages
2,263
Likes
379
Location
MA
nope but it gives me options to play with when i do move to another state with a longer range. Because 1 thing is certain.. i will not be living here in MA by 2025 that is for sure
When I think of options I generally think along the lines of why not keep the Scar as the 308 it was designed to be and then pick up a Ruger Precision Rifle bolt gun in 6.5 CM? That’s what I did, now I have both.
 
Top Bottom