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What calibers can I use with an AR15 lower?

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November 30, 2017, 01:52 AM
CD228
What calibers can I use with an AR15 lower?
In the old days I would joke " If you want to have fun ask some gun guys to name every .30 caliber cartridge" It would take the better part of the day to name them all and fights would inevitably break out over the merits of the various loadings. (if you ever get bored break out your "cartridges of the world" and count the .30 cals). Now, it's "what can I run through my AR? Smile

Back to the question at hand. Fritz gave IMHO the best advice that one can give. Figure out what you want to do and shop for a cartridge from there. There is nothing wrong with .223 or 5.56mm as a GP cartridge. Unless you want to hunt deer with it in a areathat has a caliber minimum (NY No .22, Germany Nothing smaller than 6.5mm) for example. I recently expanded to 6.5mm Grendel because I wanted a NY legal hunting cartridge with more energy at distance than a .223 that fit in a 5.56mm lower. Ammo prices are steeper than 5.56mm of course, but it's a reloader friendly cartridge.

That said, if it's just target shooting and plinking why not grab a .22 long rifle upper. It's cheap and fun.
November 30, 2017, 09:44 AM
IndianaBoy
"Just for fun, expand my horizons"

Too vague. Smile


For some people hitting steel at 800+ yards is fun.

For others, blasting a bunch of watermelons at 25 yards is fun.


Maybe I sound like a stick in the mud, but I try to gear any build towards a specific purpose that I want to achieve.

Right now I am watching 224 Valkyrie and 22 Grendel for PRS build. But there is still a good chance I'm going to go with a 223 Wylde and use 73gr ELD.



223 is a useful cartridge. Capable on deer if you take prudent shots and use a high quality bullet like the Barnes 70gr TSX.



I have often been sorely tempted to build a 9mm AR just for a fun range toy.
November 30, 2017, 11:53 AM
Il Cattivo
I like the 7.62x39 myself (a lot, in fact), but I'm increasingly intrigued with the .224 Valkyrie and I keep wondering if either case would be worthwhile necked for .257" bullets.
November 30, 2017, 12:54 PM
46and2
A suppressed 300BO Pistol/SBR is a fun gun.
November 30, 2017, 08:08 PM
RAMIUS
quote:
Originally posted by 46and2:
A suppressed 300BO Pistol/SBR is a fun gun.


What's the appeal of 300 black out? I know nothing about it.

Is it still fun without a suppressor?
November 30, 2017, 08:31 PM
cas
My contradictory answer... I find the 300/221 most boring in the AR... I've owned three of them! LMAO Doesn't make a lot of sense, I know. All three times I shot them once or twice and sold them. Last one was an impulse buy because the price was just too good. I put irons on it, hunted with it once and sold it.

Think of it was half way between the 30 Carbine and the 30-30.

(9 guns total in that caliber in 20 years)


_____________________________________________________
Sliced bread, the greatest thing since the 1911.

November 30, 2017, 08:48 PM
fritz
quote:
Originally posted by RAMIUS:
What's the appeal of 300 black out? I know nothing about it.
Is it still fun without a suppressor?

*ahem*
300blk is the among the most popular non-223 chamberings in an AR-15. Possibly THE most popular in recent years' carbine/SBR/pistol conversions.

In simple terms, 300blk is a 223 case necked up to 30 caliber. No change in bolt or mags is required, although a few magazines have feeding issues with the 200+ grain subsonic loads. Due to its larger bore, the round produces more muzzle energy than 223 -- especially in mid- to short-length barrels. A variety of factory loads are available -- supersonic loads in the 110 to 150-ish grain bullet ballpark, subsonic loads in the 200+ grain bullet ballpark.

300blk loads produce lower muzzle velocity that 223 loads. Coupled with relatively low BC supersonic-speed bullets, the 300blk isn't the optimal long distance round -- both drop and drift are inferior to 223.

Like all suppressed subsonic loads, 300blk's versions are really very quiet. Like all subsonic loads, 300blk's versions drop like a rock at distance.

Without a suppressor, 300blk for a given barrel is pretty much just as loud as 223, although maybe at a slightly lower pitch. In other words, it's loud. As for if it is still fun, that's for the user to determine. For my purposes, which is shooting at steel targets, it's much like 223. But the 300blk requires more care than 223 to hit targets as distances increase, due to the 300blk's increased drop and drift.
December 01, 2017, 07:56 AM
ed308
Add 270AR and 7mm Valkyrie to that list. Powerful AR15 wildats. And .224 Valkyrie will be coming soon. Can't wait for that one.
December 01, 2017, 08:21 AM
fritz
quote:
Originally posted by ed308:
And .224 Valkyrie will be coming soon. Can't wait for that one.

It's already here. Although supplies are tight, uppers/rifles from high-end manufacturers are available, as is ammo from Federal.

Both members of the JP Rifles team used 224 Valkyrie rifles in the Team Safari competition in October. I didn't stick around long enough after the awards ceremony to fire the JP Valkyries, but I did have time to dry fire the rifles and to fondle the ammo.

This message has been edited. Last edited by: fritz,
December 02, 2017, 11:27 AM
46and2
The 300 blk craze is/was fueled in part by the real-life Honey Badger PDW that was also popular in some video games (Call of Duty, Splinter Cell, etc) for a hot minute. Read about the AAC Honey Badger here...

It's basically a short, suppressed, AR - improved/inching toward perfection in terms the balance of size, capacity, ballistics, low noise, etc, all in one, in a familiar AR format. And who doesn't want their own Honey Badger, really?

What's not to like? Reliable with short barrels (7-8.5"+), still short with a Suppressor attached (that's one Tax Stamp) Pistol format or SBR (a second Tax Stamp), fits in a gymbag or the like... all the Ninja without the Mall... Smile

Take two, they're small...