6.5 Grendel 1000 Yards

[StarMetal]

This video will give you an idea of what the puny little 6.5 Grendel is capable of doing. Boring video but see the groups at the end:

http://www.youtube.com/watch?v=HbYlKXPbH0k

Joe

[dk17hmr]

That 6.5 seems pretty interesting.
I like my 6.8, but doubt I could do that with it at 1000 yards.

[StarMetal]

That 6.5 seems pretty interesting.
I like my 6.8, but doubt I could do that with it at 1000 yards.

The 6.8's are a fine caliber, but they do poop out much sooner then the 6.5 Grendel purely because of the lower bullet BC. So fellow on the 6.5 Forum nailed himself a 6-700 moose with his rifle. Not sure how far the shot was, but we're only talking about a 123-130 grain bullet with a definite below 2500 fps muzzle velocity.

Joe

[BD]

I've long been a fan of the 6.5x55, and the Grendel is sure interesting. But I'm waiting to see what comes out of the .450B necked down.
BD

[StarMetal]

I've long been a fan of the 6.5x55, and the Grendel is sure interesting. But I'm waiting to see what comes out of the .450B necked down.
BD

Necked down to what? If it's going to run pressure I'll tell you what is going to come out of it...broke bolts. That is unless you get one of the new super steel bolts. What's the the bolt face diameter on that 450 round?

Joe

[sheepdog]

Cough http://www.65grendel.com/gallery/65G_Drop_16_458.gif

Big fanof the grendal. willlikely be the round that replaces the 5.56 when inventories are used up.

[BD]

The first .450 necked down is the 30RAR, I believe a .270 and 6.5 may follow. The .450B is a .284 case cut off just below the neck. Case head is standard .473

Despite what you hear floating around the net, bolt thrust has not been an issue with the .450B's straight wall case. However, bolt thrust will need to be addressed with any of the necked cartridges. Remington has slightly changed the rim diameter on the 30RAR so that one can't simply re-barrel a .450B without changing to the Remington high strength bolt. If the other necked down cartridges go "mainstream", I'd expect them to use the RAR case rim/bolt as well.

Mag capacity will be smaller, so it may be less interesting to the military. But the larger case volume should give better velocity at lower pressure, interesting to a hunter. I'd love to be able to get 6.5x55 ballistics out of a 20" barrel AR platform.

BD

[StarMetal]

The first .450 necked down is the 30RAR, I believe a .270 and 6.5 may follow. The .450B is a .284 case cut off just below the neck. Case head is standard .473

Despite what you hear floating around the net, bolt thrust has not been an issue with the .450B's straight wall case. However, bolt thrust will need to be addressed with any of the necked cartridges. Remington has slightly changed the rim diameter on the 30RAR so that one can't simply re-barrel a .450B without changing to the Remington high strength bolt. If the other necked down cartridges go "mainstream", I'd expect them to use the RAR case rim/bolt as well.

Mag capacity will be smaller, so it may be less interesting to the military. But the larger case volume should give better velocity at lower pressure, interesting to a hunter. I'd love to be able to get 6.5x55 ballistics out of a 20" barrel AR platform.

BD

BD,

First I've not heard of any bolt problems with the 450 more then likely because it doesn't run as high pressure as some of the bottleneck cartridges we speak of. I've been very involved in some of these new cartridges from just about their development especially the 6.5 Grendel.

I don't know if you know all about the 30 RAR, but I will tell you the main specifics. First, we know, it's an AR15. But there are modifications. Those are the bolt, the barrel, the upper receiver. Now the carrier is the same as the AR15, but the bolt is not. The bolt is the front part of an AR10 bolt, that is the lugs, and root of it, that is the tail end that fits in the carrier, is of AR15 size. That brings ups to the barrel. The barrel has an AR10 size barrel extension thus the reason for the AR10 bolt head. To facilitate an AR10 barrel extension the upper receiver had to be larger and it is, but only in thickness, not carrier bore diameter. It has the same internal bore diameter as an AR15. Those are the major differences. Although the upper and lowers will interchange with AR15's, the bolt and barrels will not.

Now I don't know if you know there are what they call steel enhanced bolts out for the AR15. They are made from the 9310 series of steel and much much tougher then the old steel previously used.

As far as the other posters statement that when the 5.56 inventories is used up one of the current new cartridges will replace...can't be further from the truth. When the U.S. changes it's going to an entirely new rifle and new cartridge. The 6.8 could step it as it will work, but the 6.5 Grendel has too many issues in it's current configurations which are too short stubby of a body, too straight walled, too short to link efficiently. It has magazine feeding issues also. On a military rifle those things are of great importance. A better cartridge, if they wanted a 6.5 or even a 6mm, would be something along the lines of either a necked down 7.62x39 or 6.8 Rem.

Joe

[BD]

Thanks for the info. I didn't realized they were going to use the AR bolt head and barrel extension. Seems like a good idea though, as long as the upper will still drop on an standard AR-15 lower.

I don't believe the AR-15 bolt thrust/broken bolt issue is strictly pressure related. The .450B is Sammi spec'd @ 40,000 psi, (which suits me just fine), but the wildcat it came from, the 45 pro, was typically loaded in the 60,000 psi range, without any bolt issues I'm aware of. LeGendre say's they started out with higher strength steel bolts, but after quite a few guys built rifles without them, and without issues, they decided "standard" steel was OK.

It seems to me that if straight wall cartridges developed bolt thrust to the same degree as bottlenecks no one would be able to take a second shot with their .454 as the cylinder would be bound up hard. The only bottle neck revolver I've ever shot was a .22 hornet, and it would bind the cylinder every time if you weren't meticulous about degreasing the chambers after cleaning it. i don't know what the Hornet pressure equals in psi, (47,000 cup?), but it's sure not real high.

Do you know the pressures the various new AR-15 rounds are spec'd to? I'm actually a fan of pressures under 50,000 psi 'cause I like long brass life. After reading this thread I took another look at the 6.5 Grendal ballistics and I'm thinking that cartridge could probably handle most all of the hunting I do. The .450B could handle the other 10%.

These black rifles sure can shoot. It's a shame they're so homely.
BD

[StarMetal]

Thanks for the info. I didn't realized they were going to use the AR bolt head and barrel extension. Seems like a good idea though, as long as the upper will still drop on an standard AR-15 lower.

I don't believe the AR-15 bolt thrust/broken bolt issue is strictly pressure related. The .450B is Sammi spec'd @ 40,000 psi, (which suits me just fine), but the wildcat it came from, the 45 pro, was typically loaded in the 60,000 psi range, without any bolt issues I'm aware of. LeGendre say's they started out with higher strength steel bolts, but after quite a few guys built rifles without them, and without issues, they decided "standard" steel was OK.

It seems to me that if straight wall cartridges developed bolt thrust to the same degree as bottlenecks no one would be able to take a second shot with their .454 as the cylinder would be bound up hard. The only bottle neck revolver I've ever shot was a .22 hornet, and it would bind the cylinder every time if you weren't meticulous about degreasing the chambers after cleaning it. i don't know what the Hornet pressure equals in psi, (47,000 cup?), but it's sure not real high.

Do you know the pressures the various new AR-15 rounds are spec'd to? I'm actually a fan of pressures under 50,000 psi 'cause I like long brass life. After reading this thread I took another look at the 6.5 Grendal ballistics and I'm thinking that cartridge could probably handle most all of the hunting I do. The .450B could handle the other 10%.

These black rifles sure can shoot. It's a shame they're so homely.
BD

BD,

I have the pressures and bolt thrust figures somewhere. Off the top of my head the normal 5.56 Nato round will run around 52k. The blue pill test rounds are must higher. Now with that said the 6.5 Grendel, the 6.8 Rem, and the 7.62x39 all have more bolt thrust then the 5.56. It's not a pressure thing entirely. It's the total internal web area that determines bolt thrust. If the 450B runs at 50K that is well within the realm of the AR15 bolt. That 60K wildcat you mention, although will run for a while, it will soon eat the bolts up. I've heard the figures for 5.56 bolts is around 6000 rounds. The above calibers I mentioned above are far less. But the new 9310 bolt steel changes all that. Although there is another caveat and that is if the bolt is stronger, then the barrel extension lugs must be beefed up or made of better steel.

The upper receivers for the 30RAR, although having a normal AR15 internal bore, are much thicker walled, but not as big (thick) as AR10's are.

That 450B 60K wildcat should be built on either the 30RAR upper or an entire AR10 rifle.

Joe