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alamo5000
22 August 2017, 03:41
I would like you guys to discuss a little bit about 300 BLK. I actually don't have a specific question--but I do have some thoughts that I will write below. I just want to hear various or even contradicting opinions about the caliber (particularly considering my use).

Here is basically where I am going with this... as usual I am trying to figure out my next steps. I have a Reece 7 on the way but I have no host gun for it (yet).

After a little bit of thought I kind of figured 300 BLK might be a low hanging fruit here.

===

1. I absolutely LOVE shooting suppressed. If I do decide to go into this caliber I won't even bother with loading supersonic rounds. I will just reload a 5 gallon bucket full of subs to get started.

2. I don't think 300 BLK is a really practical round for SD or anything like that. That being said I would not want to get shot with it. I am guessing a 220grain heavy sub would be right about on par with .45 ACP ball ammo but I could be totally wrong there.

3. I have always wanted a PISTOL caliber carbine but so far I haven't seen anything that floats my boat yet. If I could get a 9mm and/or .45 SBR I would be all over that. The downside is I would have to SBR more guns which for something I am not 100% sure about isn't a thing yet. I don't mind SBRing more guns but I want it to be something I will be in love with 20 years from now.

4. I already have an SBR lower, mags, and really everything I would need (except the upper). Really this is part of the thing... it's sort of a low hanging fruit.

===

It's very unlikely that I will shoot at anything living with that round with the of possible exception of a pig. Everything else about it, just like almost all my other guns are strictly fun guns. Range toys, or whatever you want to call it.

I already have a bunch of 5.56 brass but if I get into this I will probably get more and just convert a few thousand rounds or more just to have around. As a habit I normally keep prepped and primed brass in storage and just dip out some as I need it.

I have a heavy buffer (H2) and an extra power spring in my lower now. Will this present a problem? I don't think so but I might as well ask. On that note is an adjustable block needed for this round? Does it have the same sometimes picky-ness of a 5.56 SBR?

What length of barrel is best and why? I am honestly leaning around 9" or so but I have no real basis on why. The only real basis I have is that my current 10.5 handles GREAT. I love the balance of it as well as the suppressor/handguard fit. If the OAL is about the same I don't think the handling will be drastically different. Like I said though, I could be persuaded one way or other. I have minimal experience with various SBR lengths.

===

Anyway I think I could get into that caliber hardware wise for pretty cheap considering I have all the other stuff already.

(The only stuff I would really need is an upper, optic, bullets, powder, and some dies for the most part)

Other things I am interested in is how the brass is converted and what kinds of powder are the way to go for subs. (Also if you know the approximate cost to reload per round that will help too)

Anything else you want to throw in there is fine. I just envision being able to shoot a lot more often without waking up the dead or pissing off the neighborhood. Basically 300 BLK in my mind will be sort of a half pistol half rifle caliber but it might just be the low hanging fruit to scratch my pistol caliber carbine itch (at least for now).

Ideally I would get a 9mm or .45 SBR but who knows. If the money fairy visits me or UW sends me a golden goose hatchling I will just get em all. For now though I am thinking through the various host options for my Reece 7. So far I have 4 or 5 contenders but where to start first is more my line of thinking.

alamo5000
22 August 2017, 03:42
Sorry for the long post. I know already. I am sitting in an airport in another country in a half way daze so please forgive me in advance for rambling on a bit.

titanse05
22 August 2017, 04:46
I think that all of the reasons that you cited are the reasons that I got into the 300 blk last year. Now it is by far my favorite rifle to shoot because it is so quiet and runs like a clock. I run a 8.7" barrel suppressed exclusively.

https://farm5.staticflickr.com/4348/35826560163_83d27b1e18_c.jpg (https://flic.kr/p/WzSuaa)

I too plan to reload for it but decided against modifying 223/556 cases and just start with 300 blk cases. IMO, anyone that had issues with ejections were using converted cases and I just didn't want to go thru the effort of converting just to introduce a potential problem. Also, when you can get S&B 220GR Subs for $0.50 per round that made the decision a no brainer for me. Once I create a nice collection of 300 blk cases I am ready to reload but don't have any data to share yet. I am stocked up and ready to use Nosler 190gr bullets over Accurate 1680 powder. I got the Noslers on the cheap at Shooters Pro Shop. Also got some 175gr bullets to experiment with.

I am currently running a H2 buffer with a standard carbine spring and haven't had an issue with the S&B subs (500-ish rounds). So I would think that you would be fine to start with what you have.

alamo5000
22 August 2017, 04:58
I think that all of the reasons that you cited are the reasons that I got into the 300 blk last year. Now it is by far my favorite rifle to shoot because it is so quiet and runs like a clock. I run a 8.7" barrel suppressed exclusively.

https://farm5.staticflickr.com/4348/35826560163_83d27b1e18_c.jpg (https://flic.kr/p/WzSuaa)

I too plan to reload for it but decided against modifying 223/556 cases and just start with 300 blk cases. IMO, anyone that had issues with ejections were using converted cases and I just didn't want to go thru the effort of converting just to introduce a potential problem. Also, when you can get S&B 220GR Subs for $0.50 per round that made the decision a no brainer for me. Once I create a nice collection of 300 blk cases I am ready to reload but don't have any data to share yet. I am stocked up and ready to use Nosler 190gr bullets over Accurate 1680 powder. I got the Noslers on the cheap at Shooters Pro Shop. Also got some 175gr bullets to experiment with.

I am currently running a H2 buffer with a standard carbine spring and haven't had an issue with the S&B subs (500-ish rounds). So I would think that you would be fine to start with what you have.

Very nice looking rifle!

If I do decide to fork out the cash I will jump in with both feet. I am glad to hear that you use an H2 buffer without issue. I have been wondering about that.

For me once I get the upper and a good red dot (T2 probably) I will probably have some coin into it. Then throw in some ammo cost for powder and primers and bullets...

I need Stickman to adopt me. [BD]

alamo5000
22 August 2017, 05:04
Do you use an adjustable block? Is it really needed?

titanse05
22 August 2017, 05:09
Do you use an adjustable block? Is it really needed?On both of my upper setups for this rifle I used a standard gas block. Before I got this Radian upper at the end of last month I ran a 10.3" Ballistic Advantage barrel and didn't have a problem with it either.

An adjustable gas block is a neat thing to have but I wanted to start with a standard and if I encountered issues, move to an adjustable gas block. I haven't found the need for one as of yet.

alamo5000
22 August 2017, 05:18
On both of my upper setups for this rifle I used a standard gas block. Before I got this Radian upper at the end of last month I ran a 10.3" Ballistic Advantage barrel and didn't have a problem with it either.

An adjustable gas block is a neat thing to have but I wanted to start with a standard and if I encountered issues, move to an adjustable gas block. I haven't found the need for one as of yet.

Good to know. Plus blocks are pretty cheap.

The more I think about it I think a 300BLK would be pretty damn fun. I have actually never shot one that I can recall. But I will be shooting mine 100% suppressed with 100% subs all the time if I end up going that route.

Rather I should say "If I go that route first".... I simply have to prioritize what I am doing. Like I said, I have several different guns that I want to get but this 300 BLK upper will overall be the cheapest to do since it is pretty much just an upper and an optic. The rest is just ammo.

Uffdaphil
22 August 2017, 06:31
I love my Advanced Armament 9" with the Recce 7. Never a malf sub or super. The uppers were selling for $1200 a few years ago. Here is a lightly used one on GB starting bid at $485.
http://www.gunbroker.com/item/683635111

The knucklehead probably won't get a lot of bids without a photo at the top of the listing. But about ten when you scroll down and he has good feedback. No reserve too!

Here is mine:

https://i.imgur.com/5qi0nfU.jpg

No idea why the double pic.

Former11B
22 August 2017, 06:48
.45 ACP Speer Gold Dot HPs are in the 890fps/404 ft-lb energy from the muzzle.

300BLK Noveske 220gr Ballistic Tips are 990fps/ 487 ft-lb energy from the muzzle.

If you use a bullet like the 194gr Lehigh Maximum Expansion 300BLK ammo, meant to expand at subsonic velocities, you'll be pushing 1000fps with probably 450+ft-lbs of energy.

Factor in a 30rd magazine and, in my opinion, better suppression, with the 300BLK and you've got a pretty good home defense set up.

Pyzik
22 August 2017, 08:02
Subscribing.

You've brought up one topic that I have overlooked in the last few days and that is .300 BLK against people. As you said, I don't want to be shot with it either but what is it's effectiveness.
Naively I assumed since it's so good against a hog, it must be pretty good against the bad guys too. Not always the case.

While I do look at my current build and many guns as "fun guns", I also look at them as SD tools. Each may have a different purpose but they should (in my opinion) all be able to serve that purpose in a defensive role.

Is it likely I'll every shoot someone with my SPR, no (and I hope not)! Same with my new .308 (which I need to get the gas right still, so it's a range toy until then). But I should be able to count on them to perform.
I'll want the same from my PDW build.

UWone77
22 August 2017, 10:16
I love my Advanced Armament 9" with the Recce 7. Never a malf sub or super. The uppers were selling for $1200 a few years ago. Here is a lightly used one on GB starting bid at $485.
http://www.gunbroker.com/item/683635111

The knucklehead probably won't get a lot of bids without a photo at the top of the listing. But about ten when you scroll down and he has good feedback. No reserve too!

Here is mine:

https://i.imgur.com/5qi0nfU.jpg

No idea why the double pic.

Those AAC uppers are great, and they are stupid cheap now on the secondary market. I wouldn't hesitate to pull the trigger on one if you want to go that route.

Former11B
22 August 2017, 11:26
Subscribing.

You've brought up one topic that I have overlooked in the last few days and that is .300 BLK against people. As you said, I don't want to be shot with it either but what is it's effectiveness.
Naively I assumed since it's so good against a hog, it must be pretty good against the bad guys too. Not always the case.

While I do look at my current build and many guns as "fun guns", I also look at them as SD tools. Each may have a different purpose but they should (in my opinion) all be able to serve that purpose in a defensive role.

Is it likely I'll every shoot someone with my SPR, no (and I hope not)! Same with my new .308 (which I need to get the gas right still, so it's a range toy until then). But I should be able to count on them to perform.
I'll want the same from my PDW build.

Ballistically, 300BLK is VERY similar to 7.62x39. I don't think you'll have any problem using it as an HD round, just pick the RIGHT one. Like 55gr FMJ isn't the best option when you could get .223 Gold Dots or something. Just an example.


Uffdaphil, that rifle looks great!

fledge
22 August 2017, 13:28
For example of subsonic HD round, YouTube the Lehigh Defense 194gr 300 blackout.

gatordev
22 August 2017, 13:39
For example of subsonic HD round, YouTube the Lehigh Defense 194gr 300 blackout.

This is why I switched out my MK18 for a 300BO HD gun. It didn't hurt that, besides buying the ammo, it cost me less than $200 to have a complete 300BO SBR, since I had the majority of the parts.

The Lehigh 194s show fantastic ballistic performance in videos, but it also won't go through much more than a wall if I miss. Plus it won't blow out my hearing inside. Realistically, I doubt I'd ever have to use it, but if I did, it should be quite the effective weapon if I'm not grabbing my pistol.

That said, I just can't find much use for 300BO on the range. I don't reload, so the ammo is too expensive compared to 5.56. If I'm trying to shoot super-quiet, I'll just shoot my MP5 for much less money. But that's just me.

Former11B
22 August 2017, 16:35
For example of subsonic HD round, YouTube the Lehigh Defense 194gr 300 blackout.

Mentioned that also. Great looking round ;)

BoilerUp
22 August 2017, 19:28
I think if you mentally equate the 300 BLK as a magnum pistol caliber you are coming at it correctly. As a rifle round it's pretty pathetic, especially the subs. I think the LeHigh bullets are the only 300 bullet that will expand worth a squat at subsonic velocities. The Barnes TAC-TX is a great choice, but is a super.

I certainly enjoy shooting mine. I'll probably enjoy it more when I get my SBR and Griffin Paladin stamps, but subsonic for me will just be for range fun and I'll stick with Barnes for the HD loads.

https://photos.smugmug.com/photos/i-ZPbVhhs/0/37f4cac7/XL/i-ZPbVhhs-XL.jpg

alamo5000
23 August 2017, 04:32
For example of subsonic HD round, YouTube the Lehigh Defense 194gr 300 blackout.


https://www.youtube.com/watch?v=JDym4GXrPRw


Very interesting stuff.

alamo5000
23 August 2017, 04:33
https://www.youtube.com/watch?v=-GyOsWuYPV0

alamo5000
24 August 2017, 11:11
Ok here is a question...

I know there are laws regarding shooting brass bullets (yes I said brass) but honestly I am not sure of the reason, what is and isn't true, or if like other things there is just no logic to such a law.

I think the brass bullet thing applies to handguns correct? Or is it all guns? If that's the case though why can you shoot 100% copper bullets and not 100% brass bullets? Like other things it makes no sense. But then again maybe someone can explain it to me better.

===

Anyway on to other subjects....that 194 grain brass Lehigh Defense bullet looks effin' awesome. They however are EXPENSIVE.

If I go through and do this 300 BLK route in an ideal world I would find some 194 grain just regular bullets so I can essentially have a single load. Going into another caliber is a pain in the ass enough but having two or three different loads for that caliber and constantly having to re-zero the gun kind of sucks.

That said since my primary purpose will be shooting steel targets or popping pigs from time to time I am wondering how to consolidate the whole load management thing into something affordable to shoot.

For example before I was shooting 115gr 9mm bullets and I got all tooled up for that but my carry loads are 124 grain HP... but eventually I just shot up all the 115 bullets I had and consolidated everything under 124 and my reloads mimic the velocity of my carry rounds. Now almost all of my practice 9mm is 124. That said I also have a lot of 147 which I actually shoot way more than everything else but it's out of different firearms. I probably shoot 80% or more 147 grain because I am addicted to shooting suppressed. With 9mm it's a little easier because I just load a lot of one thing and I am done with it for a while.

With a rifle though zeroing and rezeroing because you changed grain weights is kind of a PITA. With those Lehigh 194's they are like a buck something PER BULLET. That's just a bullet. Loaded rounds are $2 a round or more. That is insanity.

I am now really wondering how expensive it will be to shoot this damn thing. I am trying to think through the whole thing before I commit to anything. If my ammo costs are THAT high I might skip the .300 BLK thing all together.

Uffdaphil
24 August 2017, 11:31
Are the Nosler 190 grain close enough for reloading? They are relatively cheap especially buying blems x 1000. Then save the Lehighs for serious stuff.

alamo5000
24 August 2017, 11:59
Are the Nosler 190 grain close enough for reloading? They are relatively cheap especially buying blems x 1000. Then save the Lehighs for serious stuff.

I've never reloaded 300 BLK. It's kind of a weird round. Not quite rifle not quite pistol.

Reloading for pistol is a lot more forgiving than doing some serious rifle work. Usually in a rifle jumping that many grains would mean switching the powder drop.

I just looked up the 190 grain bullets and those are more like it. .25 cents a round isn't too bad. I would probably come in at .30-.35 cents per round with those.

In theory if I bought a crap load of those (or something similarly priced) it would serve 95% of my needs. If I could make my gun run subs with that grain is a whole different ball of wax. I am sure it can be done but these are things I want to ask before not after.

For example I have my cheapy 10/22 and I have tried all sorts of ammo. The .22 ammo people all try different ways to get to 'subsonic'. Some use the same grain weight bullet and just back off the charge. Others use heavier bullets. There are 3 or 4 ways to get there. Not all are effective and not all will cycle my gun. I just want to make sure I have a good supply of cheap components that will work.

I am sure it won't be an issue but it's something to learn about before I go all in.

Former11B
24 August 2017, 12:03
Reloading for pistol is a lot more forgiving than doing some serious rifle work.


.380 ACP is NOT forgiving at all!!!! You can quadruple charge a casing and still have room for a bullet lol



Are the Nosler 190 grain close enough for reloading? They are relatively cheap especially buying blems x 1000. Then save the Lehighs for serious stuff.


Which Nosler 190gr? Custom Competition? Accu Bond?

alamo5000
24 August 2017, 12:04
.380 ACP is NOT forgiving at all!!!! You can quadruple charge a casing and still have room for a bullet lol

What kind of powder are you using? I use Universal and it's pretty easy. One drop and boom. Done.

alamo5000
24 August 2017, 12:08
Are the Nosler 190 grain close enough for reloading? They are relatively cheap especially buying blems x 1000. Then save the Lehighs for serious stuff.

You are on the right track though for sure. At a dollar something PER BULLET I am halfway inclined to tell the Lehigh people no thank you. I am not sure of the terminal performance of those cheaper bullets you mention but for 90% of my shooting it won't matter. As long as it's quiet and cheap to shoot it will serve it's purpose. 90% plus of my shooting will be just plinking around and having fun so the cheaper the better.

Joelski
24 August 2017, 13:34
I use the Miller Lite vs. Stella Artois analogy. I can get a thousand rounds of Federal for $250 vs. 500 of 300 BLK subs for around the same price, maybe closer to $300. I'll have a can I can use on both rifles before my next one comes along, and I don't do ranges other than to train at certain times. I can shoot up the countryside and run the piss out of my .556 rifles for cheap and when I want to bask in mega OP coolness, I can switch over to subs and the BO. That's a lot of shooting for me. I'm lucky to average 500 - 1,000 rnds per month, more or less. Yes, I do want to reload eventually, but I'll get to it when I can. In the meantime, it's much cheaper to shoot heavy supers at around what it costs to reload using Alamo's math, so where is the motivation to reload? I can still shoot the hell out of my 300 and be satisfied for less than shooting all subs all the time.

Gator: I have no yearning for a MP5, so that's a big pile of ammo right there.

The last time I saw an all brass bullet, it was on a Beo casing and you have seen expensive until you price that shit! Beo uppers are cheepy cheep because the ammo will put you in the po house! I blinked at .45/70, but not anymore. I want a lever gun in my collection that can sling a big chunk of whatever and that's gonna be it.

OT: I've gotta buy a bird gun before November, preferably a Semi-Auto for a guided Quail Hunt. Anybody here use guns on stuff besides paper and bad guys? [:D]

I have a Les Paul and a couple of vintage Kramer electrics calling my name as well. People think I have cancer, it's just GAS! Gear poverty is a great diet! :)

Former11B
24 August 2017, 15:15
What kind of powder are you using? I use Universal and it's pretty easy. One drop and boom. Done.

I use titegroup. I mean you'd have to be really not paying attention to drop four charges in there but the tiny charge is really unforgiving

gatordev
24 August 2017, 15:23
You are on the right track though for sure. At a dollar something PER BULLET I am halfway inclined to tell the Lehigh people no thank you.

Lehigh has sales during the major holidays and you can usually knock 10% of their price. Those bullets aren't for plinking, they're for whatever work you need them to do. You can plink with other ammo.

Several years ago, PSA was selling Hornady 220s for some ridiculous price (I think it came to $.40/round), so I grabbed 250 or so. If I end up doing something that requires my 300BO to be rezeroed, I'll use the Hornady to get close, and then I usually only need 5 rounds of the Lehigh to refine/confirm.

I know everyone's gun is different, but FWIW, when I plug in a MZ of something pretty close to what comes out of my 10.5", I get a max point blank range of 0-75y (within about 1.5") with a 25y zero. For my use, I don't need much beyond that, and since the subs plummet beyond 75y, the math all works in my favor. Zeroing at 25y keeps the round count (and price!) down to make it all work.

I completely understand that may not be compatible with pig hunting, so obviously adjust as needed.

cjd3
24 August 2017, 21:10
Are the Nosler 190 grain close enough for reloading? They are relatively cheap especially buying blems x 1000. Then save the Lehighs for serious stuff.

This is the route I'm going. I'm getting pretty good subsonic results with 1680 (holy shit, this powder is dirty. I had to swap my chrome BCG into my SBR). I'll try to buy some Lehigh HD subs and run a test, then keep 2 mags for when needed.

But man oh man, is it fun to shoot.

UWone77
27 August 2017, 16:05
alamo,

I've got a 16" Wilson Combat 300 BO upper I was either going to sell or part out. If you want to shoot it long term let me know, you can play with it for awhile before you decide what to do.

alamo5000
29 August 2017, 14:25
alamo,

I've got a 16" Wilson Combat 300 BO upper I was either going to sell or part out. If you want to shoot it long term let me know, you can play with it for awhile before you decide what to do.

I am definitely game! I sent you a PM.

---

Carrying on the conversation I have heard that 300 BLK is 'optimized' for shorter barrels. I am just curious as to details about the gas system and people's preferred barrel lengths.

With 5.56 on my 10.5 there is always discussion about dwell time, but with the 300 BLK I would like to hear more about pistol length gas systems. I figure if I build an upper while I am waiting on my suppressor I am thinking that roughly 9" might be my sweet spot but I am not married to anything. That's just a rough starting point.

I just glanced at Ballistic Advantage website and their 300 BLK barrels go from 8" to 9.5" (They have more but that is what I am considering depending on what I learn).

I would also like a good fitment between the rail and the suppressor and my current 10.5 with a 9.7 rail fits great. That is a .8" difference for a near perfect fit.

9.5" barrel would mean a 8.7" rail
9" barrel would be a 8.2" rail
8.5" barrel would be a 7.7" rail

Other than rail fitment I am curious if there is a dwell time issue with this round using a pistol length gas system. If anyone has any comments on that aspect please share.

din
31 August 2017, 17:14
Pistol is the way to go. I have a 16" carbine gas and it was a total PITA to get it to run reliably. Part of that is the bbl manufacturer I'm sure, and I bought it when the round was pretty new and bugs were probably still being worked out, but unless you plan on only shooting supers, stick to pistol length. I have a 10.5" Noveske barrel with pistol length gas and haven't had any issues with it, other than getting the damn gas block pin in.

tact
31 August 2017, 19:18
I run a 9", and an adjustable gas block isn't necessary for subs or supers. The 300 is a perfectly capable SD or meat round, however, using subs for anything or than plinking and fun isn't really smart. I've even thrown in a titanium BCG and still have yet to experience any issues.

https://uploads.tapatalk-cdn.com/20170901/dbd51bff9762d62216dcb56db956bbfd.jpg

usbp379
13 November 2017, 02:31
It will be interesting to see how the new Hornady 190gr stuff works. They're claiming a subsonic load that passes FBI protocols. Price is supposed to be about $22-$23 a box.

https://www.hornady.com/ammunition/rifle/300-blackout-190-gr-sub-x-subsonic#!/

Sent from my SM-G930P using Tapatalk

BoilerUp
13 November 2017, 06:06
It will be interesting to see how the new Hornady 190gr stuff works. They're claiming a subsonic load that passes FBI protocols. Price is supposed to be about $22-$23 a box.

https://www.hornady.com/ammunition/rifle/300-blackout-190-gr-sub-x-subsonic#!/

Sent from my SM-G930P using Tapatalk

Yes, I'll be watching this. A sub with terminal performance is much needed for this caliber.

fledge
13 November 2017, 07:13
I’d keep an eye on this company too. https://discreetballistics.com/product-category/300blk/

alamo5000
13 November 2017, 09:13
Yes, I'll be watching this. A sub with terminal performance is much needed for this caliber.

Yes. Very much so. It would be even more awesome if they sold expanding bullets as reloading components.


It will be interesting to see how the new Hornady 190gr stuff works. They're claiming a subsonic load that passes FBI protocols. Price is supposed to be about $22-$23 a box.

https://www.hornady.com/ammunition/rifle/300-blackout-190-gr-sub-x-subsonic#!/

Sent from my SM-G930P using Tapatalk

I will be looking at that too. Passively of course (for now).

I looked before at expanding subs and the price was way too much among other things.

alamo5000
11 May 2018, 15:26
Reviving an old thread... I finally took the plunge and built a .300BLK upper to match my existing SBR. I saw most of the components on sale, some for really cheap so I said why not. Plus I have a Recce 7 that hadn't been shot before a few days ago.

Parts I used:

Ballistic Advantage 9" barrel (about hundred bucks delivered)
CMT UPUR 3 (about $115 delivered)
SLR 8.3" handguard and an adjustable block. (I got something like 20% off everything)

I have a SNACH charging handle and a few extra BCG but for now I am just swapping everything off my 10.5" 5.56. The optic on top is a T2.

Basically I let curiosity get the better of me but so far I kind of like it.

---

I went shopping for various grain weight and types of ammo. I found some BECK Ammo on the shelves, I never heard of them before but they had the Leighigh Defense Max Expansion on the shelves but the price was mismarked. I bought two boxes of it for $17 each out the door. I haven't shot any of that yet but I know it normally goes for $40 about, per box.

I bought some of their other ammo too and so far I can say it's pretty good stuff. I got some 220's and some 110 TSX as well as some other brands of mid weight supers.

---

I got the gas block dialed in. I will only be shooting suppressed for this gun. On gas block setting 6 (out of 15) my gun will cycle supers and subs and will lock the bolt back.

---

So far though it seems like the 300 BLK supers within 100 yards are knocking the crap out of the plate. It would certainly F something up in that 100 ish yards (and in) range.

The supers are LOUD even with a suppressor. Just as an experiment I stupidly tried to test how loud a single round would be. Needless to say I won't do that again. It really wasn't the gun or the suppressor, it was the sonic crack happening 2 feet from your face that was really unpleasant.

The subsonics were easily hearing safe. I think the ammo I have is loaded a bit stout but it's still ok. I am going to try various stuff and compare before I start reloading. I am not sure how light of bullets I can load subsonic and it still run the firearm.

What I want to do though is compare 5.56 out of a 10.5 SBR and 300 BLK out of a 9" and see how much energy I get within 150 yards. Basically do a side by side SBR comparison.

So far with my very limited amount of shooting though I kind of like it. Who knows, my impressions may change after I get 1000 rounds down range. Comparing the 300 BLK to a 7.62x39 would also be interesting information to learn about.

Overall though so far I like it.

UWone77
11 May 2018, 15:47
The supers are LOUD even with a suppressor. Just as an experiment I stupidly tried to test how loud a single round would be. Needless to say I won't do that again. It really wasn't the gun or the suppressor, it was the sonic crack happening 2 feet from your face that was really unpleasant.


I love you man, but some times you are a dumb fuck. :)

alamo5000
11 May 2018, 16:00
I love you man, but some times you are a dumb fuck. :)

In this case I'm not going to argue :)

In my defense though people put up "at the ear" numbers that are safe on a bolt gun and I had the gas all the way off.

Considering all that I figured "why not try" but screw that.

SINNER
11 May 2018, 16:09
I love you man, but some times you are a dumb fuck. :)


Guy writes a damn thesis on dB levels vs hearing loss, blows his eardrums out with a SBR.


HAHAHAHAHA

alamo5000
11 May 2018, 16:32
Guy writes a damn thesis on dB levels vs hearing loss, blows his eardrums out with a SBR.


HAHAHAHAHA

It wasn't THAT bad. On my right ear it was fine. On my left ear though it was definitely uncomfortable. Like I said, it wasn't the gun. It was the proximity to the sonic crack out of such a short barrel.

None the less that was my 'hey bubba watch this' moment for the year. [BD]

Joelski
12 May 2018, 05:03
So, related, but OT, what's a relatively quiet (-ish?) Off-the-shelf round for .223/5.56? I know the key to taming the noise level on my blackout is grams; no such solution for the smaller pill, so is there a "less noisy" alternative that us non-reloaders can take advantage of?

alamo5000
12 May 2018, 07:47
So, related, but OT, what's a relatively quiet (-ish?) Off-the-shelf round for .223/5.56? I know the key to taming the noise level on my blackout is grams; no such solution for the smaller pill, so is there a "less noisy" alternative that us non-reloaders can take advantage of?

I am not quite following the question. Grams? I don't know of people who use grams for ammo. You mean heavier grain weight bullets?

Joelski
12 May 2018, 08:30
Auto correct fuck up. GRAINS.

alamo5000
12 May 2018, 09:16
Auto correct fuck up. GRAINS.

For off the shelf ammo I have no idea but I might be able to shop around. I did my own testing a long time ago and developed a 55gr load that gets the same velocity out of my 10.5 as factory ammo but I can get off one or two rounds without it ringing my ears at all. I personally think it's quieter for a pud plinking load. Even with that though if I was going to shoot a mag of it I would definitely wear ear pro.

Without going extremely nerd on you it would be a mile long post. The type of powder matters probably the most, the bullet design matters too.

I would think your best bet for off the shelf is the Hornady 75 grain SBR ammo.

https://www.gtdist.com/hornady-5-56nato-50-bx-sbr-75gr.html

alamo5000
12 May 2018, 09:30
"The NASA Shaped Sonic Boom Demonstration, also known as the Shaped Sonic Boom Experiment, was a two-year program that used a Northrop F-5E with a modified fuselage to demonstrate that the aircraft's shock wave, and accompanying sonic boom, can be shaped, and thereby reduced. The program was a joint effort between NASA's Langley Research Center, Dryden Flight Research Center at Edwards Air Force Base, California and Northrop Grumman.

The program became, at that time (2003 according to Supersonic transport), the most extensive study on the sonic boom. After measuring the 1,300 recordings, some taken inside the shock wave by a chase plane, the SSBD demonstrated a reduction in boom by about one-third."


https://en.wikipedia.org/wiki/Shaped_Sonic_Boom_Demonstration

alamo5000
12 May 2018, 09:35
"The ground noise is expected to be around 60 dB(A), about 1/1000 as loud as current supersonic aircraft. This is achieved by using a long, narrow airframe and canards to keep the shock waves from coalescing."


https://en.wikipedia.org/wiki/Quiet_Supersonic_Technology

alamo5000
12 May 2018, 09:42
Fast forward to 22:00 in this video. He demonstrates how ultra high BC bullets have much less air disturbance downrange.

Basically the right powder with the right projectile can reduce the initial sonic crack as well as reduce the down range air disturbance (noise) levels.

Eventually they will have ultra high BC bullets that are injection molded out of certain polymers of various densities. Combine that with good gun suppression, the right powders and it's possible to reduce the sound signature of the entire gunshot, not just the boom on the end of the gun by quite a lot.


https://www.youtube.com/watch?v=lS3EP0DZgoU

alamo5000
12 May 2018, 09:44
I'm a nerd. I know, I know. :) I prefer to identify as 'smart' though. HAHAA!!

fledge
12 May 2018, 10:06
Joelski, you can’t run it in your AR but subsonic expanding 223 exists.

http://beckammunition.com/ammunition/subsonic-ammo/223-subsonic/223-55gr-rex-expanding-subsonic.html

And I’m over here wearing double earpro...

alamo5000
12 May 2018, 10:09
Joelski, you can’t run it in your AR but subsonic expanding 223 exists.

http://beckammunition.com/ammunition/subsonic-ammo/223-subsonic/223-55gr-rex-expanding-subsonic.html

And I’m over here wearing double earpro...

I can vouch for Beck Ammo. The two boxes I shot made me a believer. There are a lot of options out there.

alamo5000
12 May 2018, 10:13
Here is more information on the development of the 'low boom' sonic flight technology. Apparently that's the cutting edge for the time being. But they have already proven that you can drastically reduce the sonic boom of a supersonic object.

Gulfstream X-54 project is designed to make supersonic air travel possible. They are figuring out how to reduce the sonic boom of airplanes and bullets both.

https://en.wikipedia.org/wiki/Gulfstream_X-54

usbp379
12 May 2018, 10:17
Joelski, you can’t run it in your AR but subsonic expanding 223 exists.

http://beckammunition.com/ammunition/subsonic-ammo/223-subsonic/223-55gr-rex-expanding-subsonic.html

And I’m over here wearing double earpro...http://atomicammunition.com/ammunition/223CyclingSub.html

Sent from my SM-G930P using Tapatalk

BoilerUp
12 May 2018, 12:35
So, related, but OT, what's a relatively quiet (-ish?) Off-the-shelf round for .223/5.56? I know the key to taming the noise level on my blackout is grams; no such solution for the smaller pill, so is there a "less noisy" alternative that us non-reloaders can take advantage of?

You are looking for a quieter 5.56 round to shoot out of a standard carbine? I don't think your going to get very far on that journey.

Joelski
12 May 2018, 13:13
Hence the .300 BLK love. Chive on.

Joelski
12 May 2018, 13:17
I'm still thinking that an 18in Barrel Plus my Alpha with 223 end cap will be, at the very least less noisy, which is something/better than nothing, and probably pretty close to as good as it gets.

alamo5000
12 May 2018, 16:15
I'm still thinking that an 18in Barrel Plus my Alpha with 223 end cap will be, at the very least less noisy, which is something/better than nothing, and probably pretty close to as good as it gets.

18 inch barrels are the best overall length for suppression. It provides the right amount of pressure for most suppressors to be able to tame down. The shorter the barrel the higher the pressure blast. If you have a semi auto you still have to contend with chamber pop which is still kind of loud. There are however bullet and powder combos out there that CAN give you a slight DB reduction but aside from the Hornady SBR ammo I mentioned above I've never seen any commercial ammo making those statements.

It's scientifically possible to do, just not something that has been pursued by most as far as I know.

ChattanoogaPhil
13 May 2018, 11:49
Quiet .223 is labeled 22LR.