AR caliber understanding?

[Frogbones]

Ok..as I look for another upper in A3 format with lo-pro gas block.

I've settled on the *6.somthing cal. round.

SO there's 6.8 SPC, 6.8 rem., Grendal etc.etc.

What's the difference...I'm kinda lost in that area of AR calibers.

I think I would want a 6.8rem.

advice...clearification??

[DefensiveCarry.com]

[BadgerMan]

I'm pretty sure that 6.8x43 Remington SPC is a single chambering. As far as comparing 6.5 Grendel and 6.8x43 it seems that 6.5 is a better option if you're looking for something very accurate that will perform well at longer ranges though 6.8 seems to do better out of shorter barrels. For a "fighting rifle" I'd go with 6.8 and for hunting/long range competition 6.5. It seems that 6.8 ammo is a bit more available, but both are kind of scarce at this time compared to more established cartridges so expect to pay a premium or start reloading for them.

Edit: Forgot to mention, bullet availability for loading 6.8 should be better as it uses .277 diameter bullets, same as .270 win.

[Ram Rod]

AR caliber understanding?

My understanding is that .223 will work fine in 5.56mm rifles. Any other "calibers" make the AR-15 a variant, or merely a common platform. Same way there is no 9mm 1911. The 1911 is a 45acp. You work with what you've got......I'll work with what I know. In many ways......growing old is a comfort.

[sgb]

The 6.8 SPC is the way to go if you're looking to hunt with it or use it for self defense, the 6.5 grendel seems to have more of a paper punching following. Either way if you're going to shoot it much you're going to need to reload.

[RKM]

.223 is a good round for self defense and light hunting with the right bullet. 6.8 SPC seems to be a good round, but .223 is much more readily available. I wouldn't mind have an 6.8 SPC upper though.

[Frogbones]

Ok, to save me money. I ask this. What round in the .223 cal. would be sufficient for White tale. Deer are really thick in my area. They are coming within 100yards of my house big ones by the depth and size of tracks and droppings. Several people have hit, or been ran off the road via the deer in my area. Plus it's bringing in the bigger prey animals Cyotes, and even seen prints from a big cat...mountain lion after reaserching the prints. Mother-inlaw spotted one near our tool shed two years ago.

my barrel is a 1/9twist...so somthing in the 62gr area? Softpoint? HP? Boattale style? This is pretty new to me so info would help.

[sgb]

Ok, to save me money. I ask this. What round in the .223 cal. would be sufficient for White tale. Deer are really thick in my area. They are coming within 100yards of my house big ones by the depth and size of tracks and droppings. Several people have hit, or been ran off the road via the deer in my area. Plus it's bringing in the bigger prey animals Cyotes, and even seen prints from a big cat...mountain lion after reaserching the prints. Mother-inlaw spotted one near our tool shed two years ago.

my barrel is a 1/9twist...so somthing in the 62gr area? Softpoint? HP? Boattale style? This is pretty new to me so info would help.

223 Winchester Ranger 64gr Soft Point

[Frogbones]

Well Thanks.

I didn't even mean to post...I didn't proof read or anything. Thought I just deleted it, was going to re-do it when I got home.. Oh well.

[OldVet]

I'm not a fan of .223 for deer, seen too many fail to penetrate. But some folks do with success. Just make sure the caliber is legal for big game in your state (not allowed in some) and you use a bullet that's designed for hunting big game.

I've used it for up to coyote-sized varmits, and it's been awesome, although its penetration has been marginal with lighter, varmit weight bullets. I use primarily 55 grainers.

[Cuda66]

With your 1:9 twist, get some 55gr Barnes TSX (sold under Federal's Vital-Shok line).

It's a heavily constructed, all copper bullet that will expand well and still fully penetrate a deer's chest; my friends who hunt in MN's rifle zone with .223's swear by them, and have yet have a deer run far (less than 100 yards, normally) after being hit by one in the boiler room.

[Ring]

Wolf sells 6.5 ammo

6.5 VS Elk at 400y
http://castboolits.gunloads.com/showthread.php?t=65222

6.5 Grendel vs. 6.8 SPC


Converting the AR-15 to the 6.5 Grendel or 6.5x38mm is exactly the same as converting to the 6.8 SPC, NO special lower receiver is required.

Remove the magazine, remove the complete .223 upper, install the complete 6.5 Grendel upper, replace the magazine and you are ready to go!


Differences between the 6.5mm and 6.8mm

6.5mm = .264" bore, 6.8mm = .277" bore.


When it comes to bullet weights the 6.5 Grendel can shoot bullets from 85g to 144g but those of 100g to 125g are optimum. There are bullets available for the .277" bore from 100g to 150g but the 6.8 SPC can only handle the lighter 100g to 115g bullets.


For any given bullet weight the 6.5 mm has a higher Sectional Density. The higher the Sectional Density the better. A higher SD even at moderate velocities results in greater penetration.


For any given bullet weight the 6.5mm has a higher Ballistic Coefficient. The higher the BC the greater the retained velocity.

A 6.5mm Grenndel fired at a slightly lower velocity as a 6.8 SPC will have virtually equal power at short ranges. The 6.5mm will be superior at medium ranges and FAR SUPERIOR at long ranges. Suposedly a 6.5 Grendel has nore energy at 1,000 yards than the .308 Win due to its much higher retained velocity!!!


The 6.5mm also has a huge selection of very high quality bullets avalable including VLD (very low drag) bullets. There are none of these available for weights usable by the 6.8 SPC.

[Frogbones]

Thank all. This really helps.

[nedrgr21]

One other cartridge you should look at is the 6.5 MPC from SSK Industries - if you reload, and for cost savings you should. Same initial velocity as the Grendel so ballistics should be the same, but uses a slightly shortened, necked up .223 case - which can be found in abundance. With the other cartridges you have to change out the bolt, barrel, and mags; with the 6.5 - only a barrel swap is necessary.