What's new

AR 15 alternative calibers, what's yours?

I have a CZ 550 FS bolt gun in 6.5x55 Swede, I would love to have the 527 in 6.5 Grendel.

It took me a little over a year to get the 527, had one on backorder, then located one on line and had it in a couple of days. A 550FS in 6.5x55 is my grail gun. Love the cartridge. I am the proud owner of a M38 Swedish Mauser, a 1900 model by Mauser Obendorf with a two digit serial number, all parts matching.
 

nortac

"Can't Raise an Eyebrow"
Took my first deer with a 1906 Carl Gustoff Swedish Mauser in 6.5x55 , sporterized by Kimber.
 

OkieStubble

Dirty Donuts are so Good.
My guess is that 5.56 will remain popular much the same way other older rounds have remained popular. I don't know which of the newer rounds will become popular, if any. That's not to be contrary: the 5.56 has a lot of user momentum behind it, while the newer rounds don't as of yet.

If and when the market becomes saturated where companies are offering rifles and parts for these other calibers as much as they do for the 5.56? It can/will only drive the prices for 5.56 ammunition even cheaper. Instead of people buying .22 conversion uppers to train cheaply for their 5.56's, they will be buying 5.56 conversion uppers for their 6.8's and 6.5's because 5.56 will be $3 a box. :)
 
Last edited:
The modularity of the AR platform lends itself to a slew of alternative calibers other than 5.56/.223. I'm about to embark on a .300 Blackout build and have interest in the 6.5 Grendel as well. What are your alternative calibers, advantages and/or pitfalls for your choice and did you build it or purchase a complete assembled upper?

If I were going to pick an alternate caliber, it would be .300 Blackout. That said, I like the .223 Wylde chamber for 5.56.
 
I wouldn’t mind having a 6.8.

I have a 6.5 Grendel that is a tack driver and cheap 6.5 Grendel ammo available. But I will admit that 6.8 SPC has superior ballistics. [EDIT] By superior, I mean more effective for hunting and performs well out of a 16" barrel. I could see someone arguing that the 6.5 Grendel is better; depends on what you want.
 
Last edited:
If I were going to pick an alternate caliber, it would be .300 Blackout. That said, I like the .223 Wylde chamber for 5.56.

Also, if you are reloading a 30 cal like 308 Win or 30-06 anyways, 300 Black is very convenient. I have a 300 Black AR format "pistol" and it is a lot of fun. One day, I will get a tax stamp for it and turn it into a registered SBR.
 
The thing about a 6.8 is, it’s pushes out a 110-120gr pill. That bullet arguably makes its terminal ballistics superior to the 5.56 but... but 110gr adds up twice as fast as 5.56 weight wise. Literally. If you’re shooting out of your car, no worries. If you’re humping any distance, I don’t have to tell you that oz’s become lb’s pretty quick.

For that reason alone (weight), I’m a fan of the 5.56. But if I was defending someplace, the 450 would be pretty freaking sweet. You can bowl over a lot with a 450!
 
I started with the 6.5 Grendel back when none of the alternative calibers were popular or getting a lot of press. I did not want a micro 30 cal, and had not read a lot about the 6.8. The fact that I already had several 6.5x55 Swedish Mausers helped make up my mind. One less bullet size to deal with. I am happy with my decision and would not change it. Had I wanted a .30 cal I would probably go with a 7.62x39, plenty of cheap ammo for plinking and then I could always make my own more precisely tuned ammo.
 
Top Bottom