6.5x40 - a 6.5 SPC Improved

[adamjp]

Interesting read, but ultimately still a cartridge constrained by the AR platform. I do like the longer, more tapered cartridge but personally believe that IF a new cartridge is going to be fielded by the Western World, the only responsible way to do it is to start from scratch and design the rifle/machinegun around the cartridge. And that can only happen once we work out what the cartridge must do.

http://sadefensejournal.com/wp/?p=2414

[explorecaves]

Lots of discussion on this already.... http://www.65grendel.com/forum/showt...New-AR-varient

[JASmith]

Looking at the image in post #1, one can see the difference length of ogive exposed in the 6.5x and with the 6.5 Grendel. The 6.5x, while showing more nose room than the 6.8 SPC, is still limited with respect to the variety of low drag and VLD bullets compared to the Grendel.

[am4966]

Looking at the image in post #1, one can see the difference length of ogive exposed in the 6.5x and with the 6.5 Grendel. The 6.5x, while showing more nose room than the 6.8 SPC, is still limited with respect to the variety of low drag and VLD bullets compared to the Grendel.

Even if they went with a lower like the Six8? I mean if they resigned the platform to be in the middle/or +\- of a AR-10/AR-15 you could have a little more room to reconfigure 6mm-6.5mm cartridge for the military. I don't want to hear about the added weight. Recruit some guys that are like the size of linebackers and have all your guy's on a weight lifting program so it'll be fine. And the others lift the weights and the military have the infantry on a better diet for the task at hand. Just my uneducated thoughts and rant. Lol,

I don't mean to offend anyone that has served or is serving. Without you who knows what life would be. Like after 9-11 since I'm sure they would have kept on attacking.

[LR1955]

Even if they went with a lower like the Six8? I mean if they resigned the platform to be in the middle/or +\- of a AR-10/AR-15 you could have a little more room to reconfigure 6mm-6.5mm cartridge for the military. I don't want to hear about the added weight. Recruit some guys that are like the size of linebackers and have all your guy's on a weight lifting program so it'll be fine. And the others lift the weights and the military have the infantry on a better diet for the task at hand. Just my uneducated thoughts and rant. Lol,

I don't mean to offend anyone that has served or is serving. Without you who knows what life would be. Like after 9-11 since I'm sure they would have kept on attacking.

am49:

No, you didn't offend anyone who was or still is.

Always the guy who hasn't humped a bunch of crap that no one would ever use, because they were ordered to carry the stuff, who 'doesn't want to hear about the added weight'.

If you had served as an Infantryman in the Army or Marines, SF, Ranger, SEAL, Force Recon, then I am sure those of us who did serve in one of these outfits would shrug it off.

But, from what I read in your post, you apparently didn't serve in one of these outfits.

And that comes from someone who lifted weights while in so he could carry the weight, and still lifts today.

Diet? That one is a new one for me. Got to admit, it is one of the stranger comments I have heard.

No offense taken and no apologies necessary.

LR55

[LRRPF52]

I used to stack 3-7 empty dessert plates on my tray in the chow hall every meal.

Ahhhh, to be in my 20s again....

Of course, I was burning thousands of calories a day like an incinerator before a Congressional investigation.

As to 6.5x40, I know some guys who have tried it, and they prefer 6.5 Grendel. No reason to mess with making brass, when it's all done for you and you aren't as limited by ogive for projectile selection.

[am4966]

am49:

No, you didn't offend anyone who was or still is.

Always the guy who hasn't humped a bunch of crap that no one would ever use, because they were ordered to carry the stuff, who 'doesn't want to hear about the added weight'.

If you had served as an Infantryman in the Army or Marines, SF, Ranger, SEAL, Force Recon, then I am sure those of us who did serve in one of these outfits would shrug it off.

But, from what I read in your post, you apparently didn't serve in one of these outfits.

And that comes from someone who lifted weights while in so he could carry the weight, and still lifts today.

Diet? That one is a new one for me. Got to admit, it is one of the stranger comments I have heard.

No offense taken and no apologies necessary.

LR55

I really thought about joining the military but as soon as the recruiter found out that I had asthma he couldn't get out of the house fast enough. So I went with the alternative, college football. I was 18 during Desert Storm, and would have gladly done my share for our country after 9-11. But that wasn't going to happen, 2nd thought in the heat any extra weight would've sucked.

[Casper77]

I really thought about joining the military but as soon as the recruiter found out that I had asthma he couldn't get out of the house fast enough. So I went with the alternative, college football. I was 18 during Desert Storm, and would have gladly done my share for our country after 9-11. But that wasn't going to happen, 2nd thought in the heat any extra weight would've sucked.

Ounces = Pounds, and Pounds = Pain. Don't ask how much it weighs so long as you have EVERYTHING on the packing list you're good to go. Oh ya, and we'll divvy up the squad special-e next.

Seriously though, thanks for being willing to serve.

[sarky]

The AR-15 platform is not just limited by it's length, It is also limited by it's case head/rim diameter. The POF Revolution uses an AR-10 bolt and barrel extension(modified), with a modified BCG. By upping the parent cartridge to a .308, shortening 39/38mm you have a fatter Grendel which should provide more strength to the bolt lugs and thus allow you to take advantage of the extra powder capacity and perhaps even run it a little hotter.

[A5BLASTER]

The AR-15 platform is not just limited by it's length, It is also limited by it's case head/rim diameter. The POF Revolution uses an AR-10 bolt and barrel extension(modified), with a modified BCG. By upping the parent cartridge to a .308, shortening 39/38mm you have a fatter Grendel which should provide more strength to the bolt lugs and thus allow you to take advantage of the extra powder capacity and perhaps even run it a little hotter.

Yes but then you have a complete redesign of the mag system too have high cap mags for said round.

And probably a heavier weapon. Not sure on that part don't know what the POF system weights in at are anything.

Personally you take the grendel make the bolt out of aermet 100 and the extention rework the brass so it can have a usable pressure limit of 60k. Set your pressure data for 60k on the bolt.

And be bamm super grendel in a ar15 frame.

Now I can't tell you the lifespan of a rifle like that but it sure would be cool too test it lol.

[n9nwo]

the OP is right that it will be a new cartridge from ground up.

We have the 6.8 SPC and the Sig 6.8x51. I still think it will end up with a 6.8x45. Thus a totally new rifle.

Look for a plastic case. But I doubt we will see a C-T.

[okstatefan]

I can only speak for myself, but the 6.5 Grendel is a way to take a rifle platform that is well-known, modular, and readily available then finally mating it with a cartridge that can perform actual work.

When I got my first AR15, it was only ever going to be a plinking rifle. However, I got to plinking with it so much that I got good at plinking with it. Then in comes another AR, not iron sights or red dots, it gets a low-power scope. That led to the two rifles I was shooting most often both being in, what I consider, a cartridge good or only targets, varmints, and perhaps two-legged snakes.

So here I am with two rifles that I have taken the time to learn to drive, a few courses, fun-runs with friends, and customized to my liking. Yet, if I'm hunting in Texas and Oklahoma I grab a .308 bolt action. I tried an M&P10 in .308, but it was a FAR cry from handling an AR15. It went on two hunts and has only been fired from a bench since. I tried the 6.8, but I tried it at a bad time when ammo was very hard to get. I still have a 7.62x39 kit, and it will DRT a hog inside of 100 yards with no worries. It is just a round I never really fell for.

So why the 6.5G for me? It takes the carbine platform that I know the best and offers an intermediate cartridge that does pretty much all the work I need. It also allows me to consider getting rid of the semi-auto .308 and using the Grendel for target work as well. I'll get my upper and magazines on Wednesday and to the range on Thursday. Then I'll know a whole lot more. If my carbine runs and shoots sub MOA, I will probably get out of 7.62x39 and semi-auto .308 entirely. That would easily allow for another upper build and a stock of quality ammo.

As far as the military uses, I agree with those who suggest a new cartridge and a new platform. Figure out which round is going to be able to perform the most likely and important combat tasks, then build a great carbine/rifle to maximize that round.