having read the thread about building a AR I have a few lowers laying around and am thinking of slapping a knock around truck gun together. Nothing fancy just open sights for now or may put a red dot on it. Question is, 5.56 or 300 BO ...... ??
I am kind of tempted to build in in 300, for no reason other then I can. Would have to get a set of dies for it and get some brass. I already have 5.56 and a Grendel.
What would you guys do??

8” AR pistol in 5.56 with a red dot.(I have an Eotech on mine but overkill) blade brace on it. Fits in a tennis racket case for discrete carry. You could do the same with the 300 BO

I do want to keep it at 16 inches .... Forgot to mention that.

Build a "pistol" and run shorter barrel that doubles as a shoulder stock!

The 224 Valkyrie round was developed to bring unheard of accuracy and long range ballistic performance to the AR-15 platform.

Thats a little conflicting there LawDog ... The Valkyrie has a higher case capacity then the 5.56. You need a bit more pipe to burn that extra powder then a pistol or even a 16 inch rifle. My longer range work is covered by the Grendel anyway. All I want to do is build a knock around gun as I don't want to keep my hunting rigs bouncing around in the truck. I have the rifle set up sorted out, mostly parts out of my " left over bin" just not sure about the caliber.

Just a option new round don't know much about it! I stick with the .223 myself them fancy rounds will make a gun become a expensive club if things ever get crazy! LOL

How about a soda can launcher shoot some guy with that and who would believe that story!

Glad you said soda and not beer can launcher. That could be taken as alcohol abuse.

these work good for a carry everyday in vehicle gun. Of course anybody prone to theft can see them in your vehicle. I havn't had one since high school. Sure was a handy place for a rifle though.

https://www.cabelas.com/product/G-Lox-We...mp;gclsrc=aw.ds

IF i had a weapon that i was gonna keep in the truck think i'd stick with the .223 for the ammo being easy to get.

Can you build a 12 Gauge on an AR platform?

Nope and nope and nope.


Not going to get through the mag well or into the magazine, Don't fit through the action, To big for the bolt face ....... well just nope.

I think you should go for the 300...

I like my Kel-Tec Sub 2000 in 9mm Glock for a vehicle gun. Folds in half and 31 round mags are available for it. Same ammo as my pistol uses.

I saw some high speed/low drag operators at the Missouri dept of conservation range blow up a 300.....they were shooting next to me, had a rack of about six ar's in their booth. Noticed they were shooting at 25 yards and when I finished shooting, chained my booth then sat down to wait for cease fire I saw them both sitting at the bench and the non shooter was spotting thru a scope for the shooters....I got up to verify they were shooting at 25 and yup...

Anyway the shooter keeps racking and trying to fire this ar, aims and evidently the gun does not fire and he racks it again and slams the forward assist a few more times.........aims and boom....lower blows up.

Anyway he loaded a .223 mag in the 300 and somehow got something jammed in front of an unfired round and managed to jam it up in there and get it to go off..

To each, his own. For me, I like a hand gun in a vehicle. It's way too hard to swing a longer weapon, at least in the cabs I'm used to.

That being said a properly mounted shotgun or AR might fit the bill. Properly mounted means easily accessible and already pointed in the right direction.

Sub 2000, 9mm Glock mags, My favorite truck gun:

I like that.

i carry an 870 slug gun with buckshot in the truck 80 percent of the time.easier than getting caught with an ar or pistol in the vehicle with me living within a mile of the NY boerder.

How about 7.62x39?