hrcjon: That is one fine example of being ready for not only hearing the threat, but preventing hearing loss. We have trained a bit in some house scenarios. At this point in my life, hearing loss is very real, after years of firearm use without adequate protection. Add industrial and equipment noise damage. The amplified muffs are a fine idea , use them in matches, now attached to my bedside firearm.

i alternate, but have a 9" 300blk with a rugged micro 30 attached. i keep the micro attached at all times regardless of HD rifle/sbr/pistol. even if it was my only can, i cant see not using one when i would directly benefit from its use.

I have been hoping to find a 300blk sub round that really does expand at normal HD distances....i.e. 20-30' max.

The Novenske round looks interesting but it's pricey and I have not seen many tests for it. I don't mind spending the money if it works but the jury is still out.

https://www.midwayusa.com/prod...c-glow-tip-box-of-20

I have a 8.5" upper that I will be putting on my current pistol lower as soon as it warms up. Planning on utilizing it with my SDN-6 as my bedroom gun.

I would prefer to use a subsonic round just due to lack of noise but only if I can find one that really expands.

I’ll probably spend more time in Purgatory (if I’m lucky) for posting this, but on the left is a fully expanded Hornady 300 Blackout 190 grain Sub-X bullet recovered from test media, and on the right is a fully expanded Winchester 45 ACP 230 grain Ranger T bullet. Both were fired at subsonic velocities.

Despite what some Internet posters might believe or have us believe, there is more to wound ballistics effectiveness than the appearance of bullets recovered from test media—especially a single example of two separate bullets—but it is one factor to at least be aware of.

I originally started my 8.3" 300 build with the same intention: using subsonic suppressed for home defense. I came to the same conclusion of not finding a good option that provided the agreed upon "good enough" measure of squishing ballistics gel.

It's probably great when your objective is to be lethal and as quiet as possible, but also change magazines and be lethal to 3-400m.

But the good news is the consensus on some of the supersonic stuff is that it blows up gel really well, does kinda the same bullet-high-velocity-doesn't-like-walls that helps make the argument for an AR in the home so valid, and isn't so bad with a can. Better than a shortie 5.56 maybe?

I'm waiting on my Q Trash Panda, I have this one and a similar 10.5" 5.56 waiting for it to get out of jail. Hopefully next month.

https://i.imgur.com/dUHtR1b.jpg

I SBR'd a BCM lower a few years ago and picked up an 11" in 5.56 and a 9.5" upper in 300 BLK along with a suppressor. The thought was it was going to be my home defense gun. My unscientific testing lead me to conclude that 300BLK subs suck. If you're set on 300BLK shoot the supers suppressed.

I e got a 300 blackout upper on the way. Any ammo that’s trash or is most of it good stuff? Talking regular, not subsonic.

quote:

Originally posted by Leemur:
Any ammo that’s trash or is most of it good stuff?

As always, it depends on your purposes.

Just to cite a couple of examples, from my 300 Blackout guns the Hornady 110 grain V-MAX load is significantly more precise than S&B 124 grain FMJ. That’s not surprising based on the types of bullets involved and the costs of the two types. That does not mean, though, that the S&B stuff isn’t worth having. It’s plenty precise for the drills I usually shoot and the cardboard doesn’t care that it’s a nonexpanding bullet.

I have had good luck with the previously mentioned Hornady 110gr V-Max and Hornady's American Gunner 125gr HP. This experience is with my recently purchased PSA 10.5" pistol kit (minus lower receiver).

BTW, both of the above mentioned cartridges are on sale. TargetSports USA's price is approximately 66 cents per round. The V-Max is normally around 83 cents. The only catch is that you have to buy them in 200-rd bulk containers.

How about the 78gr Lehigh Defense round? Been a while since I ran them through the chrono but I think they were pushing 2800fps out of my 8.2 Noveske SBR. I remember them being super accurate to 100 yards. Didn’t shot them past that.

quote:

Originally posted by sigfreund:

quote:

Originally posted by Leemur:
Any ammo that’s trash or is most of it good stuff?

As always, it depends on your purposes.

Just to cite a couple of examples, from my 300 Blackout guns the Hornady 110 grain V-MAX load is significantly more precise than S&B 124 grain FMJ. That’s not surprising based on the types of bullets involved and the costs of the two types. That does not mean, though, that the S&B stuff isn’t worth having. It’s plenty precise for the drills I usually shoot and the cardboard doesn’t care that it’s a nonexpanding bullet.

I’m just looking for info on reliability.

The Magtech 123 grain FMG stuff has been perfect in my 7.5" build upper...same for the ADI 125 grain MatchKing HP (both are supers)...no function issues at all.

I know people poopoo PSA, but I just ordered a 7.5" complete upper. My YHM .30 cal suppressor should be here this summer.

Performance wise, is there going to be much difference between barrel lengths of 7.5” through 10.5”. Trying to decide if 7.5 is too short.

quote:

Originally posted by Leemur:
I’m just looking for info on reliability.

Now that we know what your question was, it makes answering much easier:
I have fired less than 300 rounds total, but both of the loads I mentioned have been completely reliable in my MCX.

quote:

Originally posted by Leemur:
Any ammo that’s trash or is most of it good stuff?
I’m just looking for info on reliability.

Cycling reliability may depend as much upon your rifle/pistol/upper as the ammo. Most supersonic FMJ ammo in the 120-150 grain ballpark should cycle just fine. However, it will likely exhibit poor accuracy and virtually no tumbling/expansion/fragmentation.

Magtech's 123 grain FMJ ammo should be high on any list of something that makes noise when the trigger is pulled and loads the next round.

quote:

Originally posted by Sourkraut:
Performance wise, is there going to be much difference between barrel lengths of 7.5” through 10.5”. Trying to decide if 7.5 is too short.

For subsonic ammo there is no practical difference in muzzle velocity or muzzle energy.

For supersonic ammo there is a difference. For typical 110 grain loads, expect a difference of about 200 fps at the muzzle, which translates to about 200 foot pounds at the muzzle. It depends upon your preferred use, but these differences are real and noticeable.

quote:

Originally posted by fritz:

quote:

Originally posted by Sourkraut:
Performance wise, is there going to be much difference between barrel lengths of 7.5” through 10.5”. Trying to decide if 7.5 is too short.

For subsonic ammo there is no practical difference in muzzle velocity or muzzle energy.

For supersonic ammo there is a difference. For typical 110 grain loads, expect a difference of about 200 fps at the muzzle, which translates to about 200 foot pounds at the muzzle. It depends upon your preferred use, but these differences are real and noticeable.

Thank you for that. I am most interested in the supersonic loads. I’m assuming the velocity/energy loss you mention is the difference between a 7.5 and 10.5 barrel. So an 8.5, or 9.5 would have a little less velocity/energy loss. It seems to me that a 3” difference in barrel length is a lot on an AR pistol.