Is it worth keeping a 308 around?

WARNING: The following is an opinion written by an asshole on the internet with no credentials, data and facts will not necessarily be present.

I think the 6.5 creedmoor is a great round that has excellent ballistic performance on targets at slightly extended ranges when compared to a .308 Winchester when evaluated for wind and drop. understanding the difference in ballistic coefficient, I know that it will carry more kinetic energy at ranges exceeding 600 yards than a .308 in a similar weight class, I don’t however, have that much faith in its ability to distribute that energy to a hard target such as a vehicle or building.

im not sure why the abilities of afghanis to carry a 60 year old stolen weapon up a mountain and drop 130 year old Russian lead from the high ground is really relevant to the discussion, it’s historically been very difficult to fight an enemy in their own backyard especially when they have the high ground and know the fastest escape route. The 6.5 CM or .338 NM won’t change that, even Mike Tyson is vulnerable to a sucker punch In a back alley. Its intellectually hollow to say the reason we are giving back control of much of Afghanistan’s countryside to the taliban is because they have the marvelous PKM with the magical 7.62x54R. I think that totally negates the fact that our soldiers, marines, airmen, and sailors have been hobbled by rules of engagement that were put together by a pacifist coalition of kindergarten teachers and were expected to engage The Enemy combatants fueled by a sense of religious duty with zero interest in the Geneva convention or any shred of human dignity. On top of that you’ve had three presidents who aren’t committed to full victory or withdrawal and aren’t willing to sacrifice election cycle performance on finishing a 20 year standoff with a bunch of well armed farmers. No need to remind most people here of a time when our ancestors (Also mostly well armed farmers) caused a similar withdrawal of the greatest military power on earth because of several well fought campaigns, high national debt and a lot of political misery. It’s damned difficult to defeat an Insurgency, always has been, always will be.

The .308 may not be today’s top performer but there are still plenty of military and civilian uses for it. I think the real reason that the 6.5 creedmoor proliferated like herpes in a frat house is that the low recoil was attractive to shooters who had only ever fired small frame ARs and it could make an inexperienced shooter into the White Feather with minimal practice. If you have the funds to have multiple rifles for specific jobs and you like filling you safe with a lot of single purpose rifles (most of us do), don’t bother keeping a .308. If you like to shoot anything from 110-240 grain projectiles at a variety of speeds with the same rifle and optic at all manner of targets, keep a trusty .30 bore in the safe and a few hundred rounds, it costs you nothing to keep it and not shoot it.
 
For a bolt gun, if you're not setup for 7.62 then yeah, go with 6.5CM I guess. Or wait a few months and there'll be someone with a thread on here asking, "is 6.5CM dead?" and getting serious responses. Someone will neck it down to a 6CM and that'll be the new thing or someone will neck down this or that magnum case making a new 6.5magnum something or other.

Someone in this thread said ".338LM and .50BMG are obsolete". WTF?

Someone in another thread said "6.5G is obsolete". Can you find better suited for competition? Yeah, probably. But it's hard to beat as the "best all around" cartridge for the AR IMO/E.

SR25 and Mk20 in 7.62... May get the 6.5CM uppers down the road, may not. But neither one is obsolete. And 6.5CM has its limitations and drawbacks too.
 
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Is it worth keeping a .308 around?

Short answer: ALWAYS keep at least one 5.56 NATO and/or 7.62x51 NATO capable rifle in your stable.

This is a no brainer and has zero to do with ballistics of either round.
Has everything to do with buying, trading for or even stealing ammo if needed.



./
 
Short answer: ALWAYS keep at least one 5.56 NATO and/or 7.62x51 NATO capable rifle in your stable.

This is a no brainer and has zero to do with ballistics of either round.
Has everything to do with buying, trading for or even stealing ammo if needed.



./

Correct. Gets back to my earlier point that there is always an argument for owning at least one firearm chambered in all the NATO small arms rounds (5.56x45, 7.62x51, 9mm). They’ll be the cheapest the longest, then the most common the longest, then the most available (by whatever price/means) the longest.
 
In my humble opinion I think that is a good plan. If you have the want to and monetary resources you should own both cartridges. I have 2 custom 308's and have the resources to rebarrel them both if I want to. Yes I am outgunned by the PKM and am subject to a good web forum tar and feathering but who cares. The cartridge with the right projectiles is sufficient for the ranges you have described. I may be new to the forum but I am not new to this debate in my circles locally. I have held out on my 308's since the birth of the 6.5 CM... Call me crazy.

Currently, however, if someone walks in and says they are just getting started I send them to the 6.5 CM. I have been shooting both and the one has made me appreciate the other. I have taken them out together (in the wind) and shot them side by side and walked away a believer. The 6.5 CM is pretty forgiving.

But I can afford both horses in my stable. I can load and stockpile for both. I have the time, energy and desire to train with both. I know my capabilities and limitations of the 308 and my loads for each barrel length. I also know my own capabilities and limitations as well and that is why I'm here (to get better).

So if it tickles your pickle to go the route you described then do it. Just avoid the PKM'S until you own a 300 NM or a 338 LM or a 300 PRC or that nasty weapon mounted on a C-130.

I love shooting so I don't mind having a disadvantage with .308 if it means I gain experience with it. Which will be fun.

If I ever encounter a PKM hopefully that means I have a 60mm mortar with me.
 
I love shooting so I don't mind having a disadvantage with .308 if it means I gain experience with it. Which will be fun.

If I ever encounter a PKM hopefully that means I have a 60mm mortar with me.
Most of us shoot rimfire from time to time. I never once considered doing away with it because of what happens in Afghanistan.
 
I love shooting so I don't mind having a disadvantage with .308 if it means I gain experience with it. Which will be fun.

If I ever encounter a PKM hopefully that means I have a 60mm mortar with me.

This is my playground. I have access to a square mile of private property now and finally get to shoot farther than 700 yards. The wind was bad 2 weeks ago when this picture was taken and it was my first time shooting 1000 yards. I shot so poorly that I decided to sign up for the online training. But the guy who took the picture shot the little sub moa group of 7 out of 10 with a stock Remington 700 308. The rock to the right of my head is where we were shooting from. We discovered that day that we need a better spotting scope for the person spotting. The lighter colored impacts are mine. The Sierra TMKs leave a different mark on the target than the SMKs do. I was shooting TMKs. We have 10 steel plates and were verifying data that day. Wind was blowing left to right. No wind meter just reading mirage (don't judge my spelling or grammer). We don't have a lot of brush that gives good wind indicators so mirage is all we get. Nothing but 308s that day.
 

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This is my playground. I have access to a square mile of private property now and finally get to shoot farther than 700 yards. The wind was bad 2 weeks ago when this picture was taken and it was my first time shooting 1000 yards. I shot so poorly that I decided to sign up for the online training. But the guy who took the picture shot the little sub moa group of 7 out of 10 with a stock Remington 700 308. The rock to the right of my head is where we were shooting from. We discovered that day that we need a better spotting scope for the person spotting. The lighter colored impacts are mine. The Sierra TMKs leave a different mark on the target than the SMKs do. I was shooting TMKs. We have 10 steel plates and were verifying data that day. Wind was blowing left to right. No wind meter just reading mirage (don't judge my spelling or grammer). We don't have a lot of brush the gives good wind indicators so mirage is all we get. Nothing but 308s that day.
That is awesome. I can't to get my bolt gun. Still waiting for my state to open up..for now I shoot 5.56 out to 550yds
 
6.5 CM is old news.
The performance at distance between the two certainly will be noticeable

That’s pretty ancient now.
The 6mm’s are pretty popular now.
 
Almost did that to this rifle. 700 LTR in 308. Glad I didn't. Hadn't shot this rifle in years, been playing with the AR-10 variants. Put a scope back on it and shot this group when getting it zeroed. Low right shot was from bore sighting. Three in the bull. View attachment 7346056View attachment 7346057
Nice shooting. I wouldn't change a thing. But when looking at the ballistics of the 7MM-08 it compares very well with the 65 CM but with a little more thump.
 
Who is this guy? Saying the 308 is irrelevant for this reason or that. What is your intended use? I'm like a lot of people on here who not only do not engage much past 1000 but also know how to make sure I'm engaging 300 and in for a guaranteed hit. I know how to use my equipment and the comments about winning against an insurgency area absolutely correct. Go pound sand dude, you're not the only warfighter around these parts.
 
Who is this guy? Saying the 308 is irrelevant for this reason or that. What is your intended use? I'm like a lot of people on here who not only do not engage much past 1000 but also know how to make sure I'm engaging 300 and in for a guaranteed hit. I know how to use my equipment and the comments about winning against an insurgency area absolutely correct. Go pound sand dude, you're not the only warfighter around these parts.
Agreed. Now he will tell you that you aren’t a vet and the US Military sucks compared to everyone else. I’m glad you said that.
 
Nice shooting. I wouldn't change a thing. But when looking at the ballistics of the 7MM-08 it compares very well with the 65 CM but with a little more thump.
I'm still going to build a 7-08, I'm just not going to cannibalize this one to do it. I've got a 700 VLS in 243 that I was going to AI but the chamber was so out of whack the AI reamer wouldn't even clean it up. But, on the bright side, I've got a nice laminate varmint stock and a good trued up action now.

Personally I can't stand a 6.5cm. Nothing against the cartridge, it's the majority of the crowd that shoots it that gets to me.
 
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Nice shooting. I wouldn't change a thing. But when looking at the ballistics of the 7MM-08 it compares very well with the 65 CM but with a little more thump.

Around 2012 there was a good bit of discussion about 7mm GPC/7 creedmoor/ 7SAC. Pretty much 6.5 CM brass necked up to 7 mm, supposedly would push 175s to around 2900 FPS with a 24” barrel and could run them out of a short action at mag length. never really caught on, but seemed like the perfect combination of high BC, lowish recoil, good energy downrange, and good component prices/availability. I guess there wasn’t much room in the market between the 7-08,.284 win,and .280 AI. Probably enough there for several separate threads comparing 7 mm rounds to the .308.
 
Hard core calibers will always be here and do what they were intended for. No special powders or bullets. They feast on basics and never go away. Designer calibers that are for the wanabees come and go.
 
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Around 2012 there was a good bit of discussion about 7mm GPC/7 creedmoor/ 7SAC. Pretty much 6.5 CM brass necked up to 7 mm, supposedly would push 175s to around 2900 FPS with a 24” barrel and could run them out of a short action at mag length. never really caught on, but seemed like the perfect combination of high BC, lowish recoil, good energy downrange, and good component prices/availability. I guess there wasn’t much room in the market between the 7-08,.284 win,and .280 AI. Probably enough there for several separate threads comparing 7 mm rounds to the .308.
I’m thinking that has to be running some pretty serious pressures to obtain that speed with that case capacity.
 
I’m thinking that has to be running some pretty serious pressures to obtain that speed with that case capacity.

My thoughts too, there was a solid 3 pages of back and forth about it on here with all the usual “data” and never a picture of a chronograph display/printout to back it up. You know how it goes. With a small primer, thick case head, and hot powders it’s possible, doesn’t mean it’s smart. That .30 TC/creedmoor case has some real marketing magic in it.

To me the centerfold cartridges like 6.5 creedmoor and 6 GT have one huge advantage, and that is that they can advertise to match riflemen first and then sell to hunters later so you don’t have to worry about the first round on the market being some round nosed, soft point, blob lobber from a Remington green box with an ES of 150 FPS. 6.5 CM has almost always been a premium product for most manufacturers, while .30-06 and .308, even FGMM, often get lumped in with the .270/ .35 whelen crowd on the rack and match Ammo is obscured by a forest of cor-lokts.
 
Pretty much 6.5 CM brass necked up to 7 mm, supposedly would push 175s to around 2900 FPS with a 24” barrel and could run them out of a short action at mag length. never really caught on ,

I’m thinking that has to be running some pretty serious pressures to obtain that speed with that case capacity.

Yeah.
Real world sucks sometimes, probably why the concept never caught on.

Do you just say whatever comes to your head??? A PKM doesn’t out range an M240 let alone a 308 bolt gun.
It does...

Anyone looked at the ballistics of that?
 
The Wikipedia page for the PKM shows a longer maximum range than the 240, by 75 meters( woohoo), it also doesnt say what gas setting was used on the 240 Or what loads are used in each. Looking at the cartridges It’s very close in performance but the .308 has a small advantage in drop at distance. PKM has 2” of extra barrel in comparison to a 240B and a tapered case shouldn’t take as much gas pressure to extract, so there’s your advantage. Still doesn’t mean I need to trade in my M1A for an SVD or swap my bolt gun for a Mosin.
 
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A 308 will be able to get a higher speed than a 7mm with the same case capacity and same weight bullets.

Finally I learn something in this thread! Assume due to greater surface area contact with the barrel (longer bullet if smaller caliber yet same weight) and would apply to any necked down cartridge, yes?
 
It’s a function of area at the base of the bullet .30 cal=.0745 iin^2 ;7mm=.284=.0633 in^2. So with the same case capacity and same powder you get roughly the same pressure,force =P*A so more surface area= more force. Acceleration =force/mass so for two bullets with equal mass (same weight) the one that gets a harder shove(more force) accelerates more and goes faster by the time it leaves the barrel. So if chamber pressure and barrel length are equal youll see higher muzzle velocity with a 150 grain .308 than you do with a 150 grain 7-08. This is why the .308 win .338 federal and .358 win still get good MV when fired from 16-18” barrels. The trade off is that 150 grain 7mm has less frontal area and a longer profile leading to lower drag and a higher BC so even if it starts slower, it won’t lose velocity as quickly and may retain more energy at extended ranges, it will also drift a bit less in wind. There may be some contribution from friction on the bearing area in contact with the rifling but it’s probably minor compared with the advantage of 18% more surface area. I’m a big fan of 7 mm cartridges and my next rifle will likely be a 7-08, but I am a bigger fan of the .30 cals because they cover a lot of bases in a good cost effective platform and they just work, there are .308 bullets that will reliably expand at speeds from 800 FPS to 3000FPS and you can load it to suit your uses. Im not able to force myself to sell firearms once I own them so I don’t foresee ever getting rid of a .308 or a .30-06.
 
A 308 will be able to get a higher speed than a 7mm with the same case capacity and same weight bullets.
Finally I learn something in this thread! Assume due to greater surface area contact with the barrel (longer bullet if smaller caliber yet same weight) and would apply to any necked down cartridge, yes?

Steelhead, with the data given for the 7 CM, 175 gr and 2900 fps compared to my chrono'd M118LR 175 gr at 2723 fps the 7 CM generates more free recoil in an equally weighted gun. Theoretically the longer equally weighted projectile should have a higher BC, for 175 SMK's 7mm is .608, .308 is .505.

I'd assume that the difference in velocity is due to more surface area for the chamber pressure to push the base of the bullet, though the bearing surface would also have to influence internal ballistics. Several interactives in the bore play with that.

(On a side note 2 rounds over 2750 fps for the 175 was gave me hard bolt lift, one round under 2750 did not, from my notes. I didn't finish that charge weight. Also, lots of bored theory reading underway.) Jphil posted while I was typing, good info well explained.
 
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I am also bored so sorry for posting a lot today. The argument was that 7cm takes advantage of the creedmoor small primer brass taking higher pressure but 7 cm was never saami rated, just a wildcat, so they may have been cranking pressure and not known or cared. I never saw any mention of case life, that would paint a clearer picture. The problem I had with it was that it was billed as almost a competitor for the .284 win assuming both rounds in a short action, I just don’t see it without a lot of pressure and heat. The creedmoor nutswingers are going to hate it when they get replaced by Sigs new super .270 and Hornady’s fancy new high volume 6mmx45. Names and information have been changed for the security of those involved, op-sec. and what not.
 
I would like to know who is actually getting over 2900fps with a 175grn bullet in a 7mm Creed with a 24” barrel. Not theoretic but actual shooting as seems very high for a short action case and a heavy for caliber bullet.
 
I run my 140s out of a 7-08 at 2900 from a 24" barrel, not killing it but about as high as I'm willing to run the pressure. I can't see a reasonable load in a 308 based case running a 7mm 175 at 2900.


I got tired of reading tea leaves a few yrs back and bought a pressure trace system. I wish I had the time to test some of these magic bullets I read about on the interwebz. I remember when I got my first 30" tube for an F-TR rifle and from what I was reading here on SH I had the slowest barrel ever made by Kreiger. I've since learned that the quantity of exaggerated velocity info on the WWW is staggering.
 
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Short answer: ALWAYS keep at least one 5.56 NATO and/or 7.62x51 NATO capable rifle in your stable.

This is a no brainer and has zero to do with ballistics of either round.

Summed up perfectly.

There will always be newer, better BC, more powerful, more accurate cartridges. But the 5.56 and 7.62 NATO cartridges will always have a role and place.
 
I don’t think anyone achieved it or will, ended up under 2800 running very hot powders. Stated 162 gr. A-max to 2950 with 41.5 gr. of 8208 XBR but never saw any chronograph data. The problem with 7 creed is the same problem with .30 TC, It’s a cool round produced 49 years too late so it fits a role that nobody Really needs. There’s all manner of 7mm cases from long actions to short magnums that will perform at those levels and the brass isn’t that much more expensive. 6.5 CM avoided that issue because it’s only common competitor in a short action was .260 and Remington never properly marketed it. People are always pushing for a free lunch, .338 LM energy with .22 short recoil and .300 blk barrel life, won’t ever happen but I guess it creates jobs.
 
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It’s a function of area at the base of the bullet .30 cal=.0745 iin^2 ;7mm=.284=.0633 in^2. So with the same case capacity and same powder you get roughly the same pressure,force =P*A so more surface area= more force. Acceleration =force/mass so for two bullets with equal mass (same weight) the one that gets a harder shove(more force) accelerates more and goes faster by the time it leaves the barrel. So if chamber pressure and barrel length are equal youll see higher muzzle velocity with a 150 grain .308 than you do with a 150 grain 7-08.

Wait, I’ve got a question on this: doesn’t the pressure increase in the 7mm relative to the .308 as it moves down the barrel? Thus offsetting the reduction in area and keeping force relatively constant?

If you have the same chamber pressure, then yes you get more force because of the increased area right as it leaves the chamber. But by the 20th inch of say a 22 inch barrel, gasses from the same amount of pressure at the chamber now have to fill an empty cylinder that’s

20*3.1416*(0.284/2)^2 = 1.267 in3

Vs.

20*3.1416*(0.308/2)^2 = 1.490 in3

That 0.223 in3 difference is 17.6% less space for the same amount of gas that created the equal pressure at the chamber. Doesn’t that therefore up the pressure on the 7mm for the last 2” of barrel?

Caveat: I know enough math to be dangerous but not enough to be good. Finance, not engineering 😉
 
I'm just getting into precision/ long range shooting, and I've decided to start with .308. I've always wanted one, and want to learn to reload with it. If I can hit 1000yds I'll be happy.

My ultimate goal is to then get a custom 6.5 since I know it's a superior round for getting to 1k+.
I'm still going to build a 7-08, I'm just not going to cannibalize this one to do it. I've got a 700 VLS in 243 that I was going to AI but the chamber was so out of whack the AI reamer wouldn't even clean it up. But, on the bright side, I've got a nice laminate varmint stock and a good trued up action now.

Personally I can't stand a 6.5cm. Nothing against the cartridge, it's the majority of the crowd that shoots it that gets to me.
I agree 100% about the CM crowd. BUT I just took delivery of one yesterday! haha. Its so much less expensive to shoot than my 7MM SAUM, and I should be able to hit the same distances that I am hitting now. Figure I can use that to practice different shooting positions etc for when I hunt with the SAUM.