65 Receiver Set with Polymer mags from PF (HOPEFULLY)

[cory]

I'm posting a thread here for a discussion that was brought up in another thread, but seemed to have gotten lost.

http://www.65grendel.com/forum/showthread.php?9230-Precision-Firearms-is-working-on-the-First-batch-of-Side-Charge-Upper-Receivers

I suggest to Mark at PF that it'd be the greatest thing since the invent of the wheel (or something along those lines), if they'd designed a 65 receiver set for the Grendel like has been done for the 6.8.

Something with a magwell that'd allow for a Pmag. Wide enough to hold a mag that won't rattle when full and long enough that we'd be able to load to a mag length of 2.290".

He suggested that the 6.8 Pmags would probably work well with the Grendel. (I inferred that the follower would have to be changed.)

Horde what say the? Can we give Mark some motivation???

Mark if you could work in some of the Light weight concepts around the industry to lighten these up as much as possible that'd be great too! HAHA

[stanc]

I would like to see a Six8-type receiver set made for 6.5 Grendel. However, I have to question the idea that 6.8 P-Mags would work well with 6.5 G cartridges. IMO, a Grendel-specific P-Mag would be needed.

Six8 P-Mags were designed specifically for the 6.8 round, which has a case diameter ~0.020" smaller than that of 6.5 Grendel. I think that will almost certainly result in improper cartridge stacking when inserting the fatter rounds into the magazine, which will in turn cause other problems (bulging magazine, unreliable feeding, etc).

[bwaites]

What advantage is served? Picking up 100 FPS, 200 FPS? Why would I go to the expense of adding another Grendel, for which I would have to load different than my current rifles, (when I am VERY satisfied with them!) to pick up such a minimal advantage?

You can't make the Grendel a .260 or 6.5 Creedmoor, there simply isn't enough boilerroom. We already can load bullets that are at max weight for the powder capacity, adding the ability to load a little longer gains us minimal improvement for the expense.

The 6.8 made sense, because they couldn't load a decent BC projectile in longer than Grendel case. We can. And we already have rifles capable of larger cases if we want to load longer bullets. Go to DPMS and get them to run 6.5 Creedmoor in their new .308 platform. Essentially the same weight as most AR15's, but lots more room for powder in that case.

[stanc]

Bill, it appears you've misunderstood the reason for a Six8-type receiver.

It is not for increased cartridge OAL. It is to enable use of P-Mags, which cannot be done with the standard AR15 mag well.

[bwaites]

Bill, it appears you've misunderstood the reason for a Six8-type receiver.

It is not for increased cartridge OAL. It is to enable use of P-Mags, which cannot be done with the standard AR15 mag well.

Actually, as I understood the Saudi order, it was for both. Though the use of PMags certainly might have been the larger of the two. If that is the real reason, I see even LESS need for a different receiver. PMAGs are cool, but they aren't the be all, end all of the AR world. I've had them break, too.

[cory]

What advantage is served? Picking up 100 FPS, 200 FPS? Why would I go to the expense of adding another Grendel, for which I would have to load different than my current rifles, (when I am VERY satisfied with them!) to pick up such a minimal advantage?

You can't make the Grendel a .260 or 6.5 Creedmoor, there simply isn't enough boilerroom. We already can load bullets that are at max weight for the powder capacity, adding the ability to load a little longer gains us minimal improvement for the expense.

The 6.8 made sense, because they couldn't load a decent BC projectile in longer than Grendel case. We can. And we already have rifles capable of larger cases if we want to load longer bullets. Go to DPMS and get them to run 6.5 Creedmoor in their new .308 platform. Essentially the same weight as most AR15's, but lots more room for powder in that case.

For one the 260 only beats the Grendel by 200-300 fps. Picking up 100+ fps isn't exactly trivial. However, you're correct you can not make the Grendel a .260 or anything of the like. What you can do is increase the options available.

Would a longer mag not allow for loading the Barnes 120gr TTSX longer allowing for NEEDED powder, or allow for loading the Barnes 127gr LRX???

How could having a reliable PMAG for the Grendel not be a GOOD thing??? The E Landers are great, but will still rattle sometimes when at full capacity. The fact is the AR15 magwell is to narrow for the Grendel to stack appropriately.

Stanc I share your concerns withe 68 Pmag, but if it could be demonstrated to work I'm open to it.

The SAAMI Grendel Chamber at max tolerances doesn't allow for you to load 0.020" off the lands, that's desired for optimal accuracy. A longer mag would fix that.

As I've said in other threads like this one. A receiver set like this would allow for a 7mm Assault Rifle type cartridge to be brought to market. That'd be very interesting.

After the Saudi contract and the Elander mag, something tells me that it's feasible that Israel could pick up the Grendel. I think it's more likely that they'd do it in the right bull pup, but a modified AR platform could certainly make it more feasible.

If PF does this and it's not to heavy, I'll be switching all of my Grendels over.

[stanc]

Actually, as I understood the Saudi order, it was for both.

I hadn't heard that. Nor does it make much sense, all things considered.

If greater cartridge OAL was actually wanted, why require a mere 0.006" increase? That's not enough to really help either muzzle velocity or ballistic coefficient.

Plus, the loading contracted for by the Saudis not only has the standard (2.26") cartridge OAL, the bullet has a low BC and is loaded to SAAMI velocity.

If that is the real reason, I see even LESS need for a different receiver. PMAGs are cool, but they aren't the be all, end all of the AR world. I've had them break, too.

Hey, I'm sure nobody would force you to buy it if you don't want it, but why oppose it for those who would like to have the option?

[cory]

...Hey, I'm sure nobody would force you to buy it if you don't want it, but why oppose it for those who would like to have the option?

Exactly!

[stanc]

Stanc I share your concerns withe 68 Pmag, but if it could be demonstrated to work I'm open to it.

Oh, I think the Six8 P-Mag should definitely be checked to determine for sure whether or not it'll work with 6.5 Grendel ammo. I doubt that it will, but I could be mistaken.

Know anyone who has a Six8 P-Mag you could borrow?

[bwaites]

For one the 260 only beats the Grendel by 200-300 fps. Picking up 100+ fps isn't exactly trivial. However, you're correct you can not make the Grendel a .260 or anything of the like. What you can do is increase the options available.

Cory, I would disagree. For the added cost of having to buy new mags, etc. 100 FPS is trivial. It's simply not enough. I can get the same by going to a 4-6 inch longer barrel, and still use the same loads and mags I have. For close in shooting, it doesn't matter at all, both 2 and 4 legged targets see no difference between 2500 and 2700 FPS out to 500 yards.

Would a longer mag not allow for loading the Barnes 120gr TTSX longer allowing for NEEDED powder, or allow for loading the Barnes 127gr LRX???

Sure, but there simply isn't enough powder space to drive them fast enough AND keep the bullet in the neck. You pick up may 1-2 grains seating long, that isn't enough to justify.[/B]

How could having a reliable PMAG for the Grendel not be a GOOD thing??? The E Landers are great, but will still rattle sometimes when at full capacity. The fact is the AR15 magwell is to narrow for the Grendel to stack appropriately.

Because it isn't a PMAG for the Grendel, its a PMAG for completely new rifle, and for one that would require huge expense to gain almost no performance.

Stanc I share your concerns withe 68 Pmag, but if it could be demonstrated to work I'm open to it.

The SAAMI Grendel Chamber at max tolerances doesn't allow for you to load 0.020" off the lands, that's desired for optimal accuracy. A longer mag would fix that.

As I've said in other threads like this one. A receiver set like this would allow for a 7mm Assault Rifle type cartridge to be brought to market. That'd be very interesting.

DPMS beat us there with the new .308 platform. That platform is ripe to be exploited exactly how you describe. Same weight as an AR15, essentially, with .308/.284/6.5 Creedmoor case capacities.

After the Saudi contract and the Elander mag, something tells me that it's feasible that Israel could pick up the Grendel. I think it's more likely that they'd do it in the right bull pup, but a modified AR platform could certainly make it more feasible.

If PF does this and it's not to heavy, I'll be switching all of my Grendels over.

Nope, I don't see enough advantage and I see LOTS of confusion coloring the picture.

[stanc]

...it isn't a PMAG for the Grendel, its a PMAG for completely new rifle...

Not exactly. It is a P-Mag for the Grendel cartridge. No doubt completely new rifles would be produced, but I know of no reason why one couldn't be assembled using all standard AR15 parts, except for the unique upper and lower receiver.

DPMS beat us there with the new .308 platform. That platform is ripe to be exploited exactly how you describe. Same weight as an AR15, essentially...

The GII is interesting, and potentially ideal for the new intermediate-length rounds like Harrison's 6.5x45 and Murray's 7x46. However, it's still longer and heavier than a Six8-type AR15.

Nope, I don't see enough advantage and I see LOTS of confusion coloring the picture.

"LOTS of confusion"??? If anybody is truly confused over the difference between a Six8 P-Mag and a standard AR15 magazine, perhaps they aren't smart enough to own guns...

[bwaites]

Not exactly. It is a P-Mag for the Grendel cartridge. No doubt completely new rifles would be produced, but I know of no reason why one couldn't be assembled using all standard AR15 parts, except for the unique upper and lower receiver.

The GII is interesting, and potentially ideal for the new intermediate-length rounds like Harrison's 6.5x45 and Murray's 7x46. However, it's still longer and heavier than a Six8-type AR15.

"LOTS of confusion"??? If anybody is truly confused over the difference between a Six8 P-Mag and a standard AR15 magazine, perhaps they aren't smart enough to own guns...

Haven't spent much time in gun stores recently, have you? Stan, its a scary world out there, with people regularly blowing up their 5.56 rifles with 300 blackout rounds, etc.

And yes, it will be confusing.

[mongoosesnipe]

I have 3 AA 25 rd mags and 4 10 rounds mags, I don't even know if any of them work as I have never used them. I exclusively us the 10 rd pmag loaded with up to 5 rounds as it is softer on the brass

[stanc]

Haven't spent much time in gun stores recently, have you? Stan, its a scary world out there, with people regularly blowing up their 5.56 rifles with 300 blackout rounds, etc.

And yes, it will be confusing.

No, Bill, the last time I was in a gun shop was September, 2011. I went in planning to buy a semi-auto version of the M4 carbine, with the intent to order a Tactical 14.5 Grendel upper from AA. Somehow I ended up buying an M1 carbine...

Perhaps you're right about people getting confused.

[cory]

Bill do you not work up new loads for each barrel when you get it? How would getting this receiver set with a new barrel be any different???

If you're not swapping out an old system, but starting an entirely new build, where's the extra cost???

The GII has a different barrel extension. Now we're talking about a custom barrel job. That's a lot more extra cost than this would be.

The Grendel is hands down the most versatile round on the market. However, it's limited mindsets that have been shown in this thread that hold it back from gaining popularity.

The Grendel is exceptional from 10.3" to 24"+ barrels at point blank range to 500 yards for hunting medium game 800yards+ for military applications and 1000+ yards for target work.

It's exceptional from the bench to a carbine course to a DMR application and would be the ultimate LMG.

The Grendel would benefit from a platform specifically designed for it, whether some people deem it worth the cost or not.