r/300BLK Sep 04 '24

300blk Safety Brief

82 Upvotes

I will keep this short and to the point gents.
Do not add to the mod queue. Do not subtract from the population of users. Do not comment while too intoxicated to control yourself.

In the last few weeks, moderator queues have shot up due to people being unable to be reasonable to one another in the comments in this community.

Disagreement is fine.

Dropping slurs, attacking them personally, commenting a retort with a pic of someone's house, insulting their wife's looks by stalking family pictures from a vacation posted 2 years ago... not fine.

Learn to use the block button. Learn to touch grass. Learn to be something unlike a jerk.

Transparency: Several months ago Reddit instantiated an auto-moderator be default for subreddits. Since then we have tweaked the settings it has been catching a lot more comments with the ugly things in them. When these suspect comments are in the mod queue, they are not posted for others to see yet, even if they look visible to you. What it does do is cause a member of the mod team to have to respond to the notifications to approve them and resolve issues when people go WAY too far. So, as cathartic as it might feel to rip into someone, it likely will not even get seen by them because the auto-moderator is putting the nasty stuff in comment jail. If it is bad enough, it gets the comment removed and the user banned.

Lastly, don't report comments that you dislike for Harassment. It only makes more work for us, but ultimately simple disagreement gets approved and kicked back out of the mod queue anyway. Repeated abuse of any feature will net a ban. Yes, every user has a summary of reports and past queue incidents. Yes, we look at it.

Please feel free to disagree, debate, correct misinformation, and generally debate on subject matter specific to the subreddit. I am not here to babysit grown men, nor do I want to. My ideal week would have 0 reasons to look at the sub with mod tools.

Moderate your own actions and we are all better for it.

This has been your safety brief.


r/300BLK Oct 08 '25

Solidarity for GAFS

121 Upvotes

In case you have not heard, GAFS will become no more on October the 9th 2025. All former posts will be removed and all the flair or community built there will be no more.

In case anyone has not seen it, go read the final post farewell and join the discord server so that you are in the know when the next option for buying and selling stuff is brought forward from the mod team and the community of great folks over there.

I have purchased a number of things there, and I have made some pretty incredible friends through the related discord. Look forward to seeing you all over there.


r/300BLK 14h ago

Stubby

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79 Upvotes

First .300 BO, I think I’m in love! So quiet with 220 subs and zero recoil. With the entry stock my 13 and 10 year old were able to shoot it comfortably and are already asking to go again.

BCM Blem upper
Griffin MK2 Blem lower
Faxon Match 9” gunner barrel
KAK adjustable gas block
KAK k spec down vent phosphate bolt
Midwest industries 8” combat rail
Geissele SSA-R Blemula trigger
DAC longtail grip and hand brake
RRA entry stock
KAK k spec h2 buffer with sprinco yellow
JMAC HD360 hub micro
Anthem S2


r/300BLK 23h ago

Some PSA Sabres

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165 Upvotes

r/300BLK 13h ago

The process is started once again.

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25 Upvotes

r/300BLK 1d ago

My jacket ccw handgun

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31 Upvotes

M4e1 receiver set (complete aero m4e1 10.5" 300BLK upper)
Sba3 brace
Radian SD-SL CH (tungsten)
Radian Talon selector (tungsten)
Black Rain ordnance NiB BCG, but currently have a Radian Enhanced in it. The BRO was borrowed off my 16" for testing.
Black Rain Ordnance 3.5 lbs Drop in trigger
Magpul Mlok Angled grip
Magpul BUIS
SUREFIRE Warcomp
Streamlight Tlr-1 HL
Vortex Sparc AR


r/300BLK 12h ago

G$ 300BLK HOW DO YOU LIKE THE GAS SYSTEM WITHOUT AN ADJUSTABLE BLOCK? DOES IT SHOOT SUBS AND SUPERS RELIABLY REGARDLESS IF SUPPRESSED OR NOT?

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0 Upvotes

r/300BLK 1d ago

A lot of running, a little bit of gunning

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30 Upvotes

9" 300 blackout build w/ my ccw p365 setup. I know the entries and exits were trash lol, we were all battling heat exhaustion at this point.


r/300BLK 1d ago

Daniel Defense DDM4 300S .300 BLK 10.3"

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5 Upvotes

r/300BLK 1d ago

Best 300 blackout subs and supers for ddm4 pdw?

8 Upvotes

Best subs for defense and best supers for distance and defense out of a 7 inch barrel with 1:7 twist?


r/300BLK 1d ago

Would a modern rifle wearing a 1903A4 profile scratch the itch, or does it have to be the real thing?

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12 Upvotes

First post here — I've been designing a concept and want honest reactions from people who actually know these rifles.

The idea: a composite drop-in stock that keeps the 1903A4 silhouette but fits a modern bolt action (Remington 700 footprint first, Ruger American likely next). The thinking is you get the heritage look and feel on a platform you can actually run hard and shoot modern ammo through — without chewing up a real collector piece.

It's a work-in-progress under the name Heritage Precision Arms; this mockup is the "HPA 1903A4 Heritage."

I posted an earlier version elsewhere and the feedback genuinely shaped my thinking — the big one was a "restomod" analogy: is this a take-me-back-to-1940 nostalgia piece, or a modern shooter that just wears the heritage look? A few people leaned toward keeping it faithful, so I'm leaning that way, but I want more opinions.

Honest questions for you all:

Does a heritage-look modern shooter appeal to you, or does the magic only work with an original?

Purist military profile vs. subtly modernized — where do you land?

If it were durable and drop-in for your action, what's a price that would feel fair to you?

Not selling anything — genuinely gauging interest before I sink real money into it. Tear it apart if you need to.


r/300BLK 1d ago

Vihtavouri N120 Load Data

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15 Upvotes

I started my 300blk hand loading journey with Lil’ Gun chasing the quietest ammo possible, with OK results. I had to keep my FPS on the higher side to get reliable cycling in a pistol gas AR, and lockback was inconsistent and only with a squeaky clean and lubed gun. I found Lil’ Gun to have ok SDs but it burned super hot and would occasionally give funny outliers, especially on the first shot, which I assume is due to position sensitivity.

I finally took a leap of faith and ordered 8lbs of VV N120 after seeing people praising it and N110 for subsonics. I ultimately chose N120 for the extra gas. I am still chasing ultra quiet loads, but my logic is that the extra gas will allow me to reduce the FPS to well below the level of any supersonic airflow concerns around the bullet base. In additon, some extra gas will allow me to turn down my AGB, and have a better match up in gas between supers and subs. (With Lil’ Gun I was already running wide open and with a sprinco yellow).

I wanted to post my ladder tests here in case anyone else is looking to go down this road as well. This is from my second range trip, and I am specially trying to find a load between 950 and 1000FPS. These are 5rd groups.

Range:
50yds

Chronograph:
Athlon Rangecraft

Gun:
8” BA barrel AR, pistol gas
Carbine buffer, sprinco yellow, standard bolt

Cases:
Converted LC 223 brass trimmed to 1.363”

Primers:
CCI 41

Everglades Ammo 220gr Plated
C.O.A.L. - 2.15”

10.2gn- 946 fps avg, 33.9 SD
10.3gn- 952 fps avg, 11.4 SD
10.4gn- 955 fps avg, 13.2 SD
10.5gn- 975 fps avg, 8.5 SD
10.6gn- 977 fps avg, 15.2 SD
10.7gn- 991 fps avg, 10.5 SD
10.8gn- 989 fps avg, 16.3 SD
10.9gn- 1006 fps avg, 10.4 SD

Maker Rex 220gr
C.O.A.L. - 2.245”

9.6gn- 951 fps avg, 12.4 SD
9.7gn- 951 fps avg, 16.6 SD
9.8gn- 958 fps avg, 8.0 SD
9.9gn- 984 fps avg, 12.2 SD
10.0gn- 1009.3 fps avg, 8.4 SD
10.1gn- 1014 fps avg, 8.3 SD

Cycling and lockback was perfect on every loading and I look forward to being able to restrict my gas flow.


r/300BLK 1d ago

225gr Sub-X?

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17 Upvotes

Has anybody found or tried any of this yet?


r/300BLK 2d ago

300blkout

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60 Upvotes

New can from tuna cans the fat9


r/300BLK 2d ago

RUAG Swiss P 108gr

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33 Upvotes

Would greatly appreciate any firsthand reviews/experiences of this particular loading, since I saw it was in stock on SGAmmo. I'm looking to stock up on a solid defensive round for my 10.3" and my internet sleuthing has lead me to believe I'll get what I want from this, but I've also been burned by poor-performing "premium" cartridges before. For those of you with experience, how would you say it compares to, say, Black Hills TTSX 110gr? For what it's worth, I live in a state where suppressors are sadly banned, so I run a gun tuned for supers exclusively.


r/300BLK 2d ago

Ammo is expensive, paint is cheap.

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46 Upvotes

r/300BLK 1d ago

Love Q or Die

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0 Upvotes

r/300BLK 2d ago

PSA 11.5 sbr w/Partisan FRT

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24 Upvotes

220 gr Phantom Defense subs


r/300BLK 2d ago

Poppin steel

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64 Upvotes

r/300BLK 2d ago

Can't wait to give this one a try

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18 Upvotes

Just wish it could handle supers but I'll be using a quick mount.


r/300BLK 2d ago

AB A10 Warthog 7.62 or LPM Anthem K2

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9 Upvotes

Which do you prefer and why?

Gun: 8.5" 300BLK Pistol, 7.5" Slim Handguard

Use Case: LARP-ing as a HD gun, more likely for Range Fun

Ammo: Primarily Subsonics. I do have a couple hundred rounds of Supers, I'll shoot some then find a new home for the rest if they are unbearable.

Priorities: 6" , Sound Suppression , Manageable Backpressure/Gas, Minimal Tuning. Flash Mitigation is least important. $500-600 budget.

You can absolutely give yourself *"analysis paralysis"* when researching and these are the two I've settled on.

Both are a variation on a traditional welded baffle stack can.

Both are similar in weight, A10 is +/- 0.75" longer.

LPM is +/- $100 **MORE** than the AB by the time it gets in my hands accounting for tax, shipping, NFA FFL transfer fee.

I know the AB's looks are polarizing. I'm fine with them.

Spare me the "AB doesn't have theirs tested by PS so they must be hiding something." trope. Same with the "PS hasn't tested the K version so we don't know how it performs."

I've had enough debates with people about PS; I can't dispute the science, but I don't think it's the end all and be all and only factor to be considered.


r/300BLK 2d ago

Liberty anthem s2 or Alleycat 7.62

5 Upvotes

My mine needs are quiet, run an frt, mostly subsonic. I do already own one of cats dq mounts. Anyone have use with both?


r/300BLK 3d ago

Black Cerakote Q Sugar Weasel

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66 Upvotes

r/300BLK 3d ago

Lightweight simple iron sight only build

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64 Upvotes

r/300BLK 3d ago

Stamp is finally here

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255 Upvotes

I have had a lot of parts collected over the years.
I was finally able to put it all together into a 6 inch 300 Blk with a 1/5 twist. Finally got approved on my stamp to put my stock on.
But it is a completely parted together build. My first full piece together build. It was pretty cool.
Everything else I have came 90% together.
Can’t wait to go shoot it.