Opinions on 6x45mm cartridge.

[Pigoutultra]

It seems to me that the 6x45mm cartridge is better than the .223 Remington ballistically. Though, it is a wildcat, it can be easily formed from the .223 Remington. It has more energy and longer range than the .223 Remington due to the increased diameter and better BC of the .243 bullets. If you had a setup for reloading this cartridge, would you convert your AR to it?

 

[longdayjake]

Its not bad, but the overall length really limits which bullets you can load into it. I personally don't think it offers enough benefits to go through the headache of dealing with an obscure round.

 

[Pigoutultra]

I've always felt that the .223 should have been necked up sooner. Necking up to 6mm is the easiest. Though you could get even more performance necking it up further, but then you start to have neck splitting problems. And yes overall length does limit you somewhat, but you still can get better bc bullets while staying within overall length guidelines.

 

[hirundo82]

I've always felt that the .223 should have been necked up sooner. Necking up to 6mm is the easiest.

Sooner? You seriously underestimate American wildcatters--.223 Rem was adopted by the military in 1964, and people were necking it up to 6mm by the next year.

 

[Pigoutultra]

Sooner? You seriously underestimate American wildcatters--.223 Rem was adopted by the military in 1964, and people were necking it up to 6mm by the next year.

What I meant was it should have been adopted my a major ammo manufacturer sooner. The 6x45 is still, sadly, only a wildcat.

 

[451 Detonics]

I have a 6.5 MPC AR in the works now. The 6.5 MPC (multi purpose cartridge) was developed by JD Jones and requires nothing more than a barrel change on the AR platform. It launches a 95 grain at 2900fps. The round has proven to be very accurate and both the 6mm and 6.5mm can utilize the excellent VDL bullets available.

 

[Pigoutultra]

That 6.5 MPC looks pretty good. A lot more energy while maintaining complete compatibility with magazines and bolt.

 

[rsilvers]

6x45 works with ordinary AR magazines. 6.5 MPC, less so. It would take a large ammo test to know how much a difference there is with magazine binding, but I would not bet on a successful outcome for the MPC.

 

[Semyon Vasilii]

if i had a reloading setup and an old AR i would build an upper for it in a heartbeat.

but i still need one with a 5.56 chamber and barrel for the 20+ cases of M855 i have here

 

[68wj]

I like the 6x45 as I do have a fondness for 6mm and it gets good numbers.

If I wanted a .223 based cartridge though, I think I would rather load the .25/223 'cause I'm one of those stubborn quarter-borers.

 

[rsilvers]

Necking a 5.56mm to 6mm would not leave enough length for the bullets in an AR magazine. One would want to shorten the case.

 

[Semyon Vasilii]

Necking a 5.56mm to 6mm would not leave enough length for the bullets in an AR magazine. One would want to shorten the case.

agree. to utilize the bullets with better BCs and SDs