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308 carbine or 300 Blackout carbine?

fredreded

Sergeant
Full Member
Minuteman
Oct 27, 2008
104
8
55
NW Kansas
Here are my thoughts, I would appreciate some feedback.

I have DPMS AP4 308 carbine I bought a couple years ago to be a "compromise" rifle. The rifle I shoot most is a purpose built LR-308 but it is HEAVY and I don't like to lug it around when out deer hunting etc. So, I bought this rifle thinking I would use it as a sort of "go-to" multipurpose rifle. The reality is though, that I just don't shoot it that much. Since it is a multipurpose rifle, I usually grab a rifle that better suits what I am going to do.

So, recently I have been thinking about selling it and getting a 300 AAC Blackout to replace it.

My "do-it" thoughts are:
This blackout will fit a purpose I don't really have covered yet (more quiet suppression)
I can still use the blackout as a multipurpose rifle when shooting supersonic rounds
It will be lighter and I will be more likely to use it.
It still has enough power (and will be legal) to hunt deer

My "don't-do-it" thoughts are:
I am giving up a good amount of range and power.
I have a pretty good stash of 308 ammo
I will need to get into an additional caliber (bullets, powder, dies, etc.)
the blackout is still a pretty new caliber and I am unsure of it's staying power. Since this is a go-to rifle, I would like to have readily available ammunition.

So, I am torn here. I would love to hear any suggestions or experiences. Thanks.
 
Re: 308 carbine or 300 Blackout carbine?

Lol.... I have pondered the same.


I keep going back to logistics though. I have 308 on hand, and plenty. But, I think I will eventually step into the 300BLK world anyway.

I've been wanting a bolt gun in 300BLK for some reason too....
 
Re: 308 carbine or 300 Blackout carbine?

Lol indeed, that is actually what got me started thinking about this. I have a friend who is about ready to take delivery of a custom built blackout bolt rifle. The round interests me but as I think about it, an AR seems to be more versatile than the bolt... particularly if a guy adds something like the Noveske switch block to it so you can turn on and off the gas easily.

The 308 on hand and readily available is probably the biggest stumbling block for me also when considering the blackout.
 
Re: 308 carbine or 300 Blackout carbine?

I have never tried but from what I read, the answer seems to be no. There is too much case capacity in the 308 to load a reliable subsonic load.
 
Re: 308 carbine or 300 Blackout carbine?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Rhinomax</div><div class="ubbcode-body">Will the SW sub. ammo cycle in an AR 10.....
Or can u load ammo that will? </div></div>

nope
 
Re: 308 carbine or 300 Blackout carbine?

Heavier weight = more Ft/lb energy @ impact . & Subsonic Vel. is just that & same for all .
But the .300wtf platform works on 8-twist & able to stabilize 200+ grn. properly & threw a Suppressor, especially for a short barrel platform .
Where as .308 platform barrel is working off your standard 10 threw 12-twist . & will not stabilize the Heavies, & threw a Can will baffle-strike .
& does not make sense to even run & dial-in Subs. unless you Run a .30 Suppressor Anyway .

Take In (rough comparative relationship) to a .357 Mag pistol @ point blank muzzle energy .
Subsonic .300 cal. Ft/lbs of energy average are 500+ ft/lb on impact @ 100 yrd. with 240's & subsonic Vel. & are greater @ 100 yrd. than Point-blank energy from .357 mag.
Also in a .300wtf Cal. platform . Running 155 wt. .30 bullets @ 1700 fps Vel. . You are getting over 800 ft/lb energy @ 100 yrd impact & over 900 ft/lb's @ 50 yrd .

Can you single-shot & accurately dial-up with accuracy 150 grn. bullets out a Suppressed .308 w/ 10 or 12 twist ? ( YES )
Will .308 & 155's @ 300+ ft/lb's energy @ 100 yrd. Kill about anything walking ? ( yes )

Sub Vel shooting in a .308 or a .300 blk platforms are all running off the Need's & want's & Purpose of platform for the person carrying ?
& for the Most Part . The 'Majority' grossly underestimate the Lethality & Power of Subsonics Vel. bullets . No Matter If they are running out a .22 Rimfire @ 50 ft/lbs impact or a Whisper @ 500 ft/lbs @ 100 yrd. ALL ARE Lethal .
.
 
Re: 308 carbine or 300 Blackout carbine?

depends on your purpose. closer ranges, the 300 will work fine and has enough power (and will sure be quiter). but for any kind of distance, you have to go with the 308. drawback is 308 AR won't cycle the subsonic and 300 does.
 
Re: 308 carbine or 300 Blackout carbine?

Thanks for the input everyone. I think I have reached a conclusion... and the answer is... yes.

Keep the 308 and save up for the blackout. I set up a false dichotomy it's shouldn't have been either or, rather, both and.

Seems to me they are different enough that either one would be an unwelcome compromise.