Nitride madness

[John A.]

With the new F1 suppressor on the backburner until the paperwork comes back one of these days, I have decided that I'm going to build an upper that would be better suited for indoor HD than the 10.5" 556 upper that is on it. And maybe for some brush hunting too.

I'm going to use the upper on top of my registered SBR lower for legality purposes and to keep everything as short, lightweight and maneuverable as possible so I can use it as God had intended.

Since I have verbally and repeatedly sworn off 300 blackout because of a particular person who all but tried to take credit for "designing" it when he didn't, I'm going to call this the 300 What'cha'ma'call-it out of the principle of it. That, and I will be using a lot of Hornady 300 whisper ammo through it. At least until after I get some brass saved up. I'm also going to try a couple hundred Palmetto Munitions powder coated subsonics to see how it performs and to at least get the feel for it because they're cheap. Or at least cheap as in about .50 a round. It was $120 per 250 rounds, which I didnt' feel was out of line considering most other ammo I'm seeing is nearly a dollar a pop.

Anyway, to the specs. You'll see what I meant with the nitride madness title in a minute. (I have gotten very fond of nitride in the last few years).

Anderson stripped upper and Ranier Arms upper parts
KAK 8.5" QPQ nitride 1:8 twist barrel/M4 feedramps and pistol gas and a CNC Warrior thread adapter
Superlative Arms Low Profile Gas Block- 416 SS Melonite
Radical Firearms Pistol length Gas Tube - Stainless Steel Nitride
12" keymod freefloat so I can recess the suppressor inside the handguard somewhat
Ares Arms Reduced Friction 158 Carpenter Steel Nitride Bolt Carrier Groups

Should make one heckuva HD upper. And easy to clean and with any luck, may extend run times between lubes, which is important when you're running a can on a DI upper.

No pictures. Just getting stuff ordered after selling some old furniture that has been stored in the basement for far too long taking up space.

 

[SHOOTER13]

Sounds like an awesome undertaking John...

Looking forward to the progress reports...

 

[CaddmannQ]

. . . so I can use it as God and Sam Colt had intended. . .

Fixed that for ya.

 

[oli700]

Fun

Really hard to find powder for it still....magnum pistol.

Really really hard to find the proper projectiles for super sonic ......IE 123gr fmj.....110gr anything not meant for an M1 carbine.....for bulk loading.
There are proper weight/profile projectiles out there but they are the spendy ones ,Barnes 110gr are like a buck per projectile

Subs are easy because they are just heavy .308

148/150gr fmj are around but they are only OK for super and by the time you reloaded , and for the money you are 2 pennies short of building a 308 Winchester cartridge

I have done a ton of lookin ......and researching if I were to stray away from 556 it would be a 375 SOCOM

Build one 300blk for a friend and it is fun to shoot...its like a nice mellow shooting round.....real fun

 

[dieselmudder]

Without sounding ignorant, whats the terminal ballistic difference between this, and pistol calibers? Ive never researched to compare one to the other. Or i guess i should ask how a subsonic 300, compares to a .45

 

[WNCmotard]

Sounds like an awesome build, and it must be contagious, cause I also ordered the stuff to build an 8.5" AR in .300blk last night. Mine will be a pistol build to be converted to a proper SBR later though. Congrats, I'll be watching.

 

[John A.]

Awesome motard. Keep me updated on the progress.

diesel, the 300 (even with subs) are 200+ yard capable though have a lot of drop, whereas 9mm subs top out about 135. Or at least the max I would consider using one.

 

[WNCmotard]

Will do John, and thanks, I'll start a thread once stuff starts rolling in. That's what drew me to the .300 in a pistol / SBR honestly, was the ability to run two different types of ammo, with or without a can with no monkeying with the gas system. Super versatile platform, and like you, in this size, I think it may be the ultimate brush hunter for medium sized (deer, hog) game. I'm really excited about this one.

 

[oli700]

Or i guess i should ask how a subsonic 300, compares to a .45

very comparable on paper.
in real life they say 300 is quieter
45 is cheaper and overabundant
swap a barrel and a bolt on an AR for 300, 45acp in AR more involved
reloading goes to the 45 acp by a light year
I think once you get out past the muzzle a bit the BC for the 300 is going to be far superior

but yes to your question they both launch similar weight bullets at similar speed when you are talking subsonic 300blk, fat and slow .....and if going to be slow you better be fat

in super no contest, 300blk all the way. Almost as powerful as X39 in equal barrel lengths but out past 200 or a little more I want to say I read the BLK becomes more efficient depending on the projectile. They both are comparable to low end 30-30 data .....people always compare them to 30-30 but hotter loaded X39 and BLK come in where 30-30 starts and then 30-30 leaves them behind....in reloading anyway

 

[John A.]

While I wouldn't mind brush hunting from a blind or stand with it at the close distances I hunt, my main reason for wanting it is for suppressed close quarters use.

The bullets that I chose to try out first to see how they do are powder coated cast 203 grainers, which should leave a pretty good wallop at close proximity.

I don't know how the lead projo's would do, but I suspect they'll deform more than a bonded or jacketed bullet.

 

[oli700]

I have shot some heavy subs in factory loads and man they are fun. It reminds me of a little shotgun slug , they ring steel good like a slug with a deep tone

 

[WNCmotard]

^^Gonna have to try some of those, love playing with slugs in the scatter guns.

 

[John A.]

Starting to receive some of the things to build the upper.

I got the nitride barrel and gas block from KAK and Superior Arms respectively. They're really sweet quality.

Looks like the gas port diameter for the 8 inch barrel with pistol gas placement is at the max recommended size to handle subsonics. But as a positive, I don't think I'll have to worry about cycling issues. Especially with the higher powered supers (which I will very rarely be using).

Though with the diameter being maxed, it's probably going to be pretty gassy unfortunately when running suppressed I think.

I have thought of ways to combat being gassed so bad when I'm shooting suppressed (other than wearing a mask) and to be perfectly honest, I may be able to seat the gas block farther back (blocking off some of the gas port) thus reducing some of the DI pressure if it is super gassy. But I'm going to shoot it first to see how "gassy" it is when I run it suppressed. It may not be bad enough to fool with.

If it is gassy, I have given some thought to possible remedies. I have even been known to use black electrical tape over the seams of the gun if it's too bad. That seems much easier and less expensive than trying to tune an adjustable gas block and achieve the same result.



After checking the gas port diameter, I hand fitted the gas block to the barrel and checked the spacing between the shoulder and the port. I used my homemade tool to do that. Which is nothing more than a forend cap that has been cut in half so the cap fits between the barrel shoulder and the rear of the gas block as it is supposed to be to ensure that the two are aligned properly.







Once it was fitted and I blocked off the barrel and used my air compressor to blow air through it to verify good flow out of the gas tube hole, I tightened the set screws so they dimpled the barrel and then used my press to countersink the marks so the setscrews will fasten more securely to the barrel.

While I plan to cover the gas block with the rifle length forend for the SD Tuber look and there will be little to no chance of the gas block being bumped, it's still a step that I think should not be overlooked. And another reason why I feel that a competent home builder can surpass the quality of a store bought upper/gun if he pays attention to the little details such as this.



Afterwards, I hit the countersink hole with some cold blue as a rust preventative because there will be no maintenance in that area. (although I know that gun blue is a form of rust itself).

I'm really happy with the overall weight of the barrel too. I think it's going to be easy to handle, and fast to get on target. Even with the suppressor attached and the handguard, barrel nut and the whole enchilada, the entire upper should clock in under about 4 1/2 pounds.

 

[oli700]

very nice.....why not an adjustable gas block ? Its the way to go for your situation for sure. My son and I just dialed in a JP for rifle he is doing and there was noting to it, really cool.
If i had to do my 8" 556 again I so would do one instead of all the tweaking with spring/buffer combos and it still wasn't perfect.
I got that JP cycling every reload under the sun and soft as hell, the adjustment is just so finite
I imagine with some shooting you could run every combination to perfection with a quick twist of an allen key. And I bet you could find a sweet spot that would reliably run most everything .....just my 02

 

[John A.]

I had a JP adjustable years ago.

After about 2 years of shooting it, the adjustment screw backed off over time and I hadn't noticed.

I was shooting and the gun stopped cycling, and some smoke was floating out the front of the handguard and got home and took it off, I quickly saw the adjustment screw was MIA.

I initially thought that my gas tube gave way, but that wasn't the case.

I never did find it.

Loctite might've helped, but would've made making the adjustments difficult at best (especially when I was tuning it), and with the heat involved, probably wouldn't have lasted long anyway. After that incident, I never could trust another.

 

[oli700]

well they must have heard ya because they have a cool little set screw in the one I played with

300blk has such pressure swing with loads

this one is supposed to be fail free but it costs....but then again suppressor and build , cost is probably worth it
http://slrrifleworks.com/index.php?route=product/product&product_id=124

anyway I suppose you researched it all out and know the 300 nuances with pressure

 

[John A.]

My old adjustable had a screw in the top of it and the tip of the screw had a pointy tip on it kind of like how a needle valve works, which essentially plugged the gas port the deeper that you tightened. It also included its' own gas tube, which was punctured to allow the set screw to work, much like how a dishwasher install kit does to your pipes when you're putting one in the first time.

Thinking about it more, is possible that my old one wasn't a JP brand. Though I'm pretty certain that it was. That was probably 9 years ago so don't hold me to it.

I have researched how great the pressures vary in the different 300 loads. They're all over the place. Especially when going from supersonic to subsonic or vice versa, though I will be primarily using subs and suppressed, so I can tune the gun if I have to if it doesn't run the way I am looking for. And I'm not going to be shooting supers through it while suppressed either because that just defeats the purpose altogether. If I deer hunt with the gun and supers, the can will stay at the house. Otherwise it'll have a steady diet of subs and the suppressor because that is my whole purpose of making it. And the increased range and power than I can do with 9mm's.

Here is one page that I found interesting concerning blackout pressures. The gas port sizes are all over the place, depending on whether you plan to shoot subs, supers, or a mix of both. I also found it interesting that the said the velocity actually increased in a few cases when using a suppressor. I can't understand how that would be possible, though I'm taking them at their word and at face value. But anyway, here's the page I was talking about. http://micromoa.com/300-blk-port-size-testing/

 

[oli700]

I really think a build like that is an ideal tight woods gun for hunting or defensive......I only hold back to call it one of the ultimate's in a SHTF because the rounds arent out there but other than that what a great Jack of all trades for the the thick deciduous forest you call home

 

[John A.]

I agree about ammo availability. I was in the same boat when I had a 6.8spcII. That was well before I started reloading anything, and I'm feeling more confident about it now, though I'd still have a serious learning curve moving over to rifle cartridges. Especially resizing and trimming.

But one thing I have noticed, the blackout is becoming more popular. Even my rinky dink wally world are starting to stock it, so that's a step in the right direction and proof positive that they're gaining traction "mainstream".

 

[oli700]

That was well before I started reloading anything, and I'm feeling more confident about it now, though I'd still have a serious learning curve moving over to rifle cartridges. Especially resizing and trimming.

aint no thing.......your all over it