Convert to 300 BLK or Not...

[MrGiggles]

I have wanted an AR for years now, and had a like new Smith and Wesson MP15 Sport 2 fall into my lap as a partial trade for a truck that I was selling.

It's a nice shooter and all, but it has limited usefulness as a .223. There is very little varmint hunting in this area. I have aspirations to hunt Coyotes, but have yet to actually realize them. That is just about the only practical use I can think of.

I deer hunt quite a bit, but .223 is marginal at best for that. I've seen a lot of posts that show 300 BLK as being a pretty decent whitetail cartridge at <150 yards with a ~125 grain bullet. My AR is a lot shorter and lighter than my .270 deer rifle. This area is very hilly, and the longest shot I have ever taken was 200 yards. Most are less than 100. I can always use the .270 for open country.

I reload, and have almost 300 rounds of 223, some loaded and some not, and primers/powder. Bullets are only slightly more expensive.

From what I understand, the only thing I need to change is the barrel to accommodate .300. Midway has an AR-Stoner barrel on sale for around 100 bucks.

So for any that have done the conversion, was it worth it?

 

[Mike C2]

I have a .300 Blackout but don't shoot it much. It's an interesting cartridge and really comes into its own supressed. But I don't own a suppressor.

I shoot .223 at paper a bunch because it's cheap. Great for all positions practice and just for giggles.

For real work, I have a 6.8 SPC. That's the gun that gets strapped in the jeep everytime. It takes a different bolt and magazine, but IMO, it is the best choice for hunting in the AR-15 platform that is commonly available.

 

[cmb3366]

300blk is a fun cartridge to shoot for a reloader, I don't think I'd bother with it if I were tied to factory ammo. Everything from 100gr to 250gr is fair game, and with pistol length gas, it is reliable even with mouse fart subsonics. Where the round really shines for me is cast bullets, it gives me a semi-auto plinking round with some thump that is dirt cheap to shoot in bulk. I say go for it.

 

[adcoch1]

You may want to look at just building an upper for 300 blk and then you don't have to choose the cheapest I've been able to price out an upper minus bcg is $194 with the barrel being $100 of that. All you need extra is a cheap gas block, gas tube, and upper casting. Use your bcg and charging handle, or buy extras for another $100.

Sent from my LGLS740 using Tapatalk

 

[adcoch1]

Plus a cheap free float grip... sorry, forgot to mention that. That was $39

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[Ibmikey]

The 300 Blackout has provided me with more fun and giggles than any of my other AR's. Although i love shooting an AR and have taken Texas pigs with the 5.56 round i put down my biggest hog ever (350+ pounds) with a Blackout....125 gr .Sierra TNT one shot.
I have three AR's and a AR pistol in 300 BO all of which are a great deal of fun to shoot, something about pushing a .30 cal bullet out of an AR barrel is special. As indicated it is a reloaders cartridge, no special steps and can be loaded numerous times...i load only supersonic and use pulled or cheap 147 gr bullets for plinking.

 

[MagnumWill]

My vote is also for .300 Blackout. I have 3 ARs in .223 and one in .300, and I've fallen in love with it and wish my other uppers were chambered in it. I use one .223 for my 3-gun and plinking because .300 is a little more expensive (not way more like everyone wants you to believe), but the .300 is awesome that I can put some 124gr rounds through it and it acts just like an AK, but then put 220gr subsonics and it has less recoil than a .223. VERY versatile. With .223 your bullet size can only vary by about 40 grains total, whereas Blackout can vary by over 100 depending on what you want to use it for.

 

[LeonCarr]

Neat round, neat concept, but I prefer .223/5.56 and if I need a deer/hog round the 70 Grain Barnes TSX works way better than it should .

Just my .02,
LeonCarr

 

[wally]

Another vote for building/buying a .300 Blackout upper, reuse the bolt, carrier, and charging handle to save money initially.

Eventually you can sell the M&P upper if you can't bring yourself to shoot 5.56.

IMHO .300 Blackout would really take off if someone convinced Wolf/Tula/Uly to make steel cased ammo for it at prices similar to their 5.56 offerings.

 

[mavracer]

I love my Blackout but like Leon said there are some 223/5.56 rounds that work really well for deer/hogs, unless regulated to a larger caliber by the state, I'd save a bunch of $$$ and just buy some premium hunting ammo for the 5.56

 

[Sav .250]

When in doubt ............sit tight! Especially if you have to ask for help!

 

[mavracer]

I'd also add that I wouldn't have my Blackout as my only AR got to have a 5.56 too.

 

[justice06rr]

If you hunt and reload, the 300blk is a good caliber for the AR15.

Eventually you can sell the M&P upper if you can't bring yourself to shoot 5.56.

IMHO .300 Blackout would really take off if someone convinced Wolf/Tula/Uly to make steel cased ammo for it at prices similar to their 5.56 offerings.

Keep the 5.56 upper; there's no sense of selling it when the caliber is widely used and available.

Just build the 300BLK upper separately.

Ammo manufacturers will not make this caliber widely available because it is not widely used. Believe me, I tried holding my breath for that after building two 300BLK AR's a few years ago and just giving up and sold them since I don't reload or hunt.

 

[jmr40]

I deer hunt quite a bit, but .223 is marginal at best for that. I've seen a lot of posts that show 300 BLK as being a pretty decent whitetail cartridge at <150 yards

With the best loads it is a wash at best and the way I look at it the 300 is a step down in performance. The 300 is useful as a suppressed round. For hunting the 223 with good bullets is vastly under rated and very capable for deer and deer sized game out to at least 150 yards. It isn't good for anything larger, but neither is the 300.

The various 6.5 and 6.8mm offerings made to work in the AR platform are the only ones with enough advantage over 223 to consider. And even then I'd go straight to another platform if I wanted something bigger than 223.

 

[jmorris]

I have a .300 blk AR, it wouldn't be my first choice for hunting medium game with an AR. Inside 150 the 458 socom has a lot more energy and at longer ranges the 6.5 Grendel has better ballistics.

 

[ColoradoMinuteMan]

Since you are a reloader you may consider the .277 Wolverine cartridge. It is another option that will allow you to use all of the "standard" 5.56 AR15 parts minus the barrel, just like the .300 AAC Blackout. You can purchase brass and complete hunting cartridges for the .277 as well as reloading dies. There is also an active wildcat community that can give you a lot of advice and share experiences with you. The .277 will give you >90% of the 6.8SPC performance without the need for a specialized bolt and magazines.

Some more information:
http://ar15hunter.com/the-ferocious-277-wolverine-is-a-cartridge-to-watch-in-2015/
http://www.maddogweapons.com/

 

[aubie515]

I have a 300BO in a bolt action and in an AR15. I hunt with my bolt action as it sports a 16" barrel and even with my suppressor on it, it's still light...

300BO isn't for everyone, but it's for me.

I don't believe anyone has said the 300BO is the same as a 6.8SPC, etc etc...these threads seem to get side tracked all the time.

OP didn't ask about 6.5/6.5, so why bring it into the conversation.

 

[Ibmikey]

Aubie....thanks for saying what i was thinking....ask about a .22 and often it ends with a 44 Mag I have taken critters with the 300 BO known to be hard to put down so " it works for me" but i also know the limitations of the cartridge and would keep my shots under 200 and more like 100 yards for effective kills. Handloading for lots of shooting is a must.

 

[ColoradoMinuteMan]

I don't believe anyone has said the 300BO is the same as a 6.8SPC, etc etc...these threads seem to get side tracked all the time.

Correct, nobody said the 300AAC is a 6.8SPC, and nobody here is attacking the 300AAC. Opinions were asked for, opinions were given. I don't think providing some comparison to other cartridges that are well suited for the proposed purpose is going off the rails.

 

[MCMXI]

I have a 300 BLK SBR arriving any day now and have shot thousands of rounds through 7", 9", 12" and 16" barrels using full-auto and suppressed ARs/M4s. I really don't see the 300 BLK as a serious hunting option out here in MT but I can see the appeal in the South or East where tree stands in wooded areas are the norm. My reason for a 300 BLK SBR is my desire for a dedicated home defense/fighting carbine that will be used 100% suppressed. Short of a full-auto H&K UMP in .45 ACP/.40 S&W I don't think there's a better choice than the 300 BLK for this purpose.

 

[Blade First]

"Ammo manufacturers will not make this caliber widely available because it is not widely used."

I'm guessing you don't get out much.

The round [usually 110g-240g loads] is incredibly popular these days for a variety of reasons. Major mfrs. have recognized that .300BLK has a substantial future.

This is a versatile round with broad applications, and it is usually quite affordable. If you save your spent 5.56 brass, chop it and reload with a .30 caliber bullet, you will be able to shoot at a truly inexpensive rate.

 

[gojuice101]

It was worth it for me, but I built it mainly for hunting. VA does not allow 223 for hunting, but I wanted to use my AR (along with the same mags and BCG) so 300AAC was a great alternative.

As stated above, a 277 Wolverine also fits the bill, but that didn't exist when I built my 300. I've wanted one since I heard about it, but haven't built one yet. More expensive than a 300AAC though.

 

[Tirod]

I hear a lot about how .223 isn't good enough for deer. My AR pistol with 10.5" barrel will put out a 70 OTM bullet downrange to 70-80 yard and still carry 1,000 foot pounds of force. That is the floor for ethical use.

A 16" will easily go much further, the real issue is how often do hunters see deer that far away? Terrain, vegetation, coloration, time of day, their stand location - reading around on the net, listening to where hunters are shooting in the woods, discussing it with them, and my own experience over 40 year leads me to think a 100m shot is out of the ordinary. For the most part hunters simply can't see a deer that far in the woods.

.300BO will increase the foot pounds of the projectile but the tradeoff is a shorter effective range vs .223 and it increases bullet drop at the longer distances. If that is what fits your actual hunting distances and you can take advantage of it, then change up. It's the same thinking that resulted in my 10.5" pistol, along with expanded seasons and personal defense capability.

If your shots are longer, out to 300m, then 6.8SPC has twice the power of .223 at longer ranges and would be the better answer. You match the ballistic properties of the round to how you hunt. All too often some try to adopt a cartridge and then find they are forced to change how they hunt to fit the cartridge, and that is why the gun becomes a safe queen or is sold off.

Along the lined of alternate cartridges, if more power at short ranges is the goal, then you might be interested in .375 SOCOM. 2200 ftlbs at the muzzle with 2200 fps and with under 300gr bullets the drop is only a foot at 300m. Alternately going subsonic with 400+ gr bullets is possible for shorter ranges. Those are generalizations but the potential is there and it does work from an AR15 using stock GI mags.

The problem isn't so much if you want to build a .300BO or 6.8, it's can you stop there?

 

[cfullgraf]

The problem isn't so much if you want to build a .300BO or 6.8, it's can you stop there?

Lay's Modern Sporting Rifles, eh? Nobody can build just one.

 

[MrGiggles]

Well, it's done.

I ordered an AR-Stoner stainless barrel from Midway, a barrel wrench, .300 BLK dies, a case holder/length gauge, and I picked up some 110gr FMJ .308 projectiles today.

I just need to grab some powder, looking at H110, but it more or less depends on what I can get locally.

I may go ahead and make another complete upper out of the .223 barrel, I haven't decided yet.