Alternative Upper Calibers for my Colt LE6920CA

[vmassarano]

I bought my Colt LE6920CA about 3 years ago and have been considering buying a new upper in a different caliber to mate with my lower.

I want longer range (maybe 600-800 yards, or more) while maintaining lethal hitting power. I've been considering the 300 Blackout and the 6.5 Grendel, but there may be something else out there I haven't considered.

Uppers aren't cheap and I want to get it right the first time. And of course, I want to be able to find ammo, and at reasonable prices.

Suggestions / recommendations?

[BajaJames83]

Maybe 6.5 Grendel or 6.8 spc

[penguin0123]

Define "lethal hitting power". What is "lethal" to a rabbit isn't always "lethal" to a buffalo.

556 can hit at 6-800 with more accuracy than you might imagine. 77gr bullets arriving at 12-1400 fps is nothing to laugh at.

If you want "longer range", why would you even consider 300Blk?

6.5G would be a much better choice. It arrives at similar muzzle velocity as 556 but carries almost double the payload. Keep in mind that at 800yds, 6.5G is roughly equivalent to a 10mm contact shot. So if you think whatever you are hunting is going to be whacked by a 10mm, then you can whack it with a 6.5G at 800.

But there are better game in town for "long range". Go to a large frame and go 6.5CM or 260. Heck, they make 300WM semi autos.

[patriot_man]

Honestly I think some 77 grain SMK bullets would do more for you then getting a new upper in a different caliber.

[Lonestargrizzly]

45 ACP

[Jimi Jah]

I bought a Radical 6.5 Grendel for $499 and it's great. Load it up with Hornady match and hit the long range.

Grendel and 7.62x39 are more fun than 5.56. Get one of each. My 20" 5.56 doesn't get used much these days.

[captainsavaho]

Get 18, 20 and 24 inch uppers with 1/8 or 1/7 twist.
223 or 556 with 62 to 77 grains.

AND don't forget the must have 762x39 and
the 50 BEOWULF uppers !!!

Yes it is expensive as ishh but it's a must have


If you are going for longer range then there's
nothing like them bolt actions.

I recommend 6.5 creedmoor, 338 Lapua, 300wm
and good ole 3006

[Osgon]

45 ACP

for long range? can't be serious. might as well as throw rocks.


OP, look into 6.8 SPC II

[Lonestargrizzly]

for long range? can't be serious. might as well as throw rocks.


OP, look into 6.8 SPC II

That's what happens when you don't actually read the OP

[vmassarano]

As for "lethal hitting power", I mean bringing down medium game at 600+ yards. In a worst case scenario, I assume that could also include a "human" threat assuming no body armor.

I started out thinking about the 300 Blackout and got very excited until I reviewed the ballistics. I'm now leaning toward the 6.5 Grendel, and glad to see so many recommending it since I want to use my existing M4 lower. My only concerns are ammo availability and cost.

Also, I would like to get a good price on the upper. Glad to hear the "Radical 6.5 Grendel for $499" was a good buy. I may need the extra money to eventually buy a bolt in one of those larger calibers.

[vmassarano]

Jimi Jah - - Where/when did you buy your Radical 6.5G upper?

[penguin0123]

As for "lethal hitting power", I mean bringing down medium game at 600+ yards. In a worst case scenario, I assume that could also include a "human" threat assuming no body armor.

I'll bring up mountain goats. Although they are smaller than "medium" game, they are tough; and most shots are >250/300yds because they'll see you coming and scram. Recommended cartridges for that animal all carry more energy than 6.5G can muster. Look up whatever medium game you have in mind, look at their average kill distance and cartridge (308, etc) and get a ballpark energy requirement.

A human does not shrug off an encounter with a 77gr projectile at 1200fps. Years of fighting in dirka-dirka-stan have given plenty of evidence.

It almost feels like you should keep your M4 an M4, and get a bolt action for your medium game.

[vmassarano]

Thanks penguin0123. Good suggestions. Getting a quality Rem700 in .308 is still an option in my mind.

[jeremyro]

I have 300blk and 458 socom and while 458 is a great choice for making large fruit explode, I mostly shoot 5.56 because it is cheap and I don't have to reload it. yet.

[crufflers]

The PA Radical 7.62x39 upper for $199 and maybe an AIM BCG and some $15 mags seems like a good deal.