18.6-20in 300BLK AR Barrel?
- Thread starter Slowbalt
- Start date
r34skyline
CGN Ultra frequent flyer
Odin works might have one. I think lothar walther might make something as well.
Definitely gonna be special order. Keep in mind the 300 bo is optimized for use around 9ish inches. And in the us. 16 inch is all thats needed for their nfa rules so the longest you would see regularly.
Definitely gonna be special order. Keep in mind the 300 bo is optimized for use around 9ish inches. And in the us. 16 inch is all thats needed for their nfa rules so the longest you would see regularly.
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Depending on what gas system you want we have IBI 18.6 300 black out barrels in stock. I'm assuming you want a pistol length. If so shoot us an email. If you want something special just let us know because our new order of barrels will be here in four weeks and we can add to the order if you like. Right now we have IBI 18.6 1/8 twist 5r rifled pistol length barrels for ar-15 in stock for 399.00.
Cheers, RWA
Cheers, RWA
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I had one built for my Bushmaster ACR and just experimented with gas port size opening it up slightly until it would cycle my loads. At the time custom was the only option and it was built from a McGowan blank.
Don't listen to the garbage about it being optimized for whatever length or that it's pointless without a suppressor. What it means is that all it needs to work well is 9-10 inches unlike a 223 that loses a bunch of velocity as the barrel gets short. The 300BLK gets around this by using faster burning pistol and shotgun powders but it still works perfectly with an 18.6 inch.
Mine shoots sub moa with my handloads and cycles everything from 110gr supersonic through to 208gr subsonics. I had the barrel made with a carbine length gas system because the ACR piston system needs a bit of length to fit it in there. I may have been able to modify things to get a pistol length to work but the carbine system works just fine on the longer barrel.
Just be sure you know what you're getting into if you decide to get one. Just like the rest of these fancy new cartridges that are supposed to be an improvement over the 223/5.56 in the AR platform the 300BLK is not a miniature 308win just like the 6.5 Grendel is not a miniature 6.5 Creedmoor. You are sacrificing a lot of velocity which results in a lot less energy downrange if you are planning to hunt with it.
I don't use my 300BLK for hunting as I have better options available to me and don't feel l need to hunt with it just because I want to carry a black rifle hunting. When I did carry it hunting I had decided that I would not be shooting at an animal past 150 yards and I made sure that I was using a projectile that would expand at the lower velocities.
As you can see in the chart going longer with 300BLK continues to yield higher velocities all the way up to a 24 inch barrel so when people say it's optimized for short barrels I ask them what they are basing that opinion on because there is no evidence that I've seen to back it up.
It works well in a 9 inch barrel and it works better in a 20 inch barrel, it works well with 110gr projectiles and it works well with 200+gr projectiles. It's a very versatile cartridge, especially if you're a handloader and can take advantage of it's versatility.
I've been shooting and handloading for the 300BLK for a few years now and have owned four 300BLK rifles, a 10 inch PWS piston driven AR, an AR I built with a custom 12 inch barrel, a 16 inch Rem 700 AAC-SD, and my 18.6 ACR, they've all shot well and have been accurate. It's a great cartridge as long as you don't expect it to perform like a 308 win.
Don't listen to the garbage about it being optimized for whatever length or that it's pointless without a suppressor. What it means is that all it needs to work well is 9-10 inches unlike a 223 that loses a bunch of velocity as the barrel gets short. The 300BLK gets around this by using faster burning pistol and shotgun powders but it still works perfectly with an 18.6 inch.
Mine shoots sub moa with my handloads and cycles everything from 110gr supersonic through to 208gr subsonics. I had the barrel made with a carbine length gas system because the ACR piston system needs a bit of length to fit it in there. I may have been able to modify things to get a pistol length to work but the carbine system works just fine on the longer barrel.
Just be sure you know what you're getting into if you decide to get one. Just like the rest of these fancy new cartridges that are supposed to be an improvement over the 223/5.56 in the AR platform the 300BLK is not a miniature 308win just like the 6.5 Grendel is not a miniature 6.5 Creedmoor. You are sacrificing a lot of velocity which results in a lot less energy downrange if you are planning to hunt with it.
I don't use my 300BLK for hunting as I have better options available to me and don't feel l need to hunt with it just because I want to carry a black rifle hunting. When I did carry it hunting I had decided that I would not be shooting at an animal past 150 yards and I made sure that I was using a projectile that would expand at the lower velocities.
As you can see in the chart going longer with 300BLK continues to yield higher velocities all the way up to a 24 inch barrel so when people say it's optimized for short barrels I ask them what they are basing that opinion on because there is no evidence that I've seen to back it up.
It works well in a 9 inch barrel and it works better in a 20 inch barrel, it works well with 110gr projectiles and it works well with 200+gr projectiles. It's a very versatile cartridge, especially if you're a handloader and can take advantage of it's versatility.
I've been shooting and handloading for the 300BLK for a few years now and have owned four 300BLK rifles, a 10 inch PWS piston driven AR, an AR I built with a custom 12 inch barrel, a 16 inch Rem 700 AAC-SD, and my 18.6 ACR, they've all shot well and have been accurate. It's a great cartridge as long as you don't expect it to perform like a 308 win.
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No, but I could chronograph my 9mm pistol and my 9mm Kriss Vector to give the upper and lower numbers. My guess is that it will be similar but probably only a couple hundred fps difference compared to the 1000fps we see in this chart. 5 grains of powder in a 9mm is only going to give so much velocity no matter how long the barrel is. I'm sure I could experiment with different powders and potentially take advantage of the longer barrel in my non restricted 9mm but I really don't care about the numbers on a noise maker that never gets shot past 100 yards and isn't going to be used on big game.
Winner, Winner, Chicken Dinner.
Any specific dealers? Seems I've checked them all and couldn't find anything. (Well I did find ATRS could make a custom one, but at 750$+ too rich for my blood, even if it was the best barrel in the known universe)
Thanks for the detailed reply! Very interesting info in here.
I did feel like the ''Its only designed for a suppressed PDW, long barrels won't work" was bullsh*t. Ford F150 is designed for work, but you absolutely can go get a pint of milk with it too...
What did you think about the report? One reason (of many) I am looking into this caliber is the very fact it burns its powder very fast. I am an absolute fan of long barreled .22s as with the right ammo the bullet impact is way louder than the report since the powder charge is long burned by the time the bullet exits the barrel. So if I could get a centerfire to be quiet-ish would be absolutely great!
You must be running factory ammo. My 10 inch PWS AR would not cycle factory subsonic even though I could handload the same projectile for it and it would cycle perfectly. My ACR with 18.6 and carbine length gas system will cycle subsonic no problem. I did however size my own gas port for that barrel.
They're a little finicky when running subs but handloading really simplifies the 300BLK.
I think you can name them just not post a link to them.
I talk about how great the guys at TOA are all the time, I just don't post links or anything more than telling people to call them.
ThatM305Guy
CGN frequent flyer
- Location
- North Texas
Will be following this as I also would like one.
