Public toilets?

[mark23]

I dont design shit, I pick apart the work of others...so in my professional opinion 10.3 is dumb and right out. 11.5 provides a myriad of benefits over 10.5 for minimal increase in OAL.

Real talk though, just because a certain design is what made it to production doesnt mean that's what the optimal design is. Cars are a great example of this

I think the short length design also has to do with running a suppressor, so effectively it's about the length of a regular M4 when suppressed

 

[cbh13]

Ugh all the AR stuff finally showed up at my FFL gonna go grab it after work and look over everything.

 

[Shemp]

I think the short length design also has to do with running a suppressor, so effectively it's about the length of a regular M4 when suppressed

So of that's true then they valued OAL over optimal performance, which is still silly but I'm not an operator so I cant use operator words.

Still would be better served with 11.5

 

[mark23]

So of that's true then they valued OAL over optimal performance, which is still silly but I'm not an operator so I cant use operator words.

Still would be better served with 11.5

12.3" per my calculations

 

[AC-130 Above]

It's not that simple, and I'm definitely not bashing 10.5 inch barrels or shorter barrels. They just don't perform as well as longer barrels and the trade off in performance for 3 inches of barrel length might not be worth while to some of us who use the rifle defensively.

The people who use the MK18 quickly switched to 77 grain 5.56 because they quickly found 62/55 grain ammo wounding is marginal (no yaw/fragmentation) , even at close quarters and over penetrates as a result (not much of a military worry in a non-permissive environment). The beauty of 5.56 at higher velocities in self defense at close quarters is Yaw = grenade like fragmentation, especially with M193, that ensures that bullet fragments that exit the body are non lethal to anyone else. That little plus is also why there was a dramatic shift in the military and LE in the mid 90's away from 9mm sub guns as entry weapons. CQ users dropped the 9mm sub gun almost over night due to over penetration. As a matter of fact M193 at 3000fps is less of an over penetrator than a lot of self defense hand gun ammo launched out of 4 inch pistol barrels...different topic/different day. Both M193 and M855 in 10.5 inch barrels exit the barrel at the bottom end of the fragmentation velocity. The minimum fragmentation velocity of M193 is 2700 fps....to insure over penetration isn't a worry at CQ it needs to be above 3000 fps to achieve that. For M855 2900 fps is the over penetration no worries range. Both of those rounds exit the 10.whatever inch barrel below the optimal fragmentation range and will over penetrate....like through rooms in your house over penetrate. Just something to consider when thinking of short barreled 5.56 platforms.

Never thought about over penetration. Interesting. So 77 grain 5.56 is optimal when trying to reduce/eliminate over penetration? Along with a longer pistol barrel

 

[AC-130 Above]

In a perfect world without NFA and SBR, I believe a lot of folks would go with a 14 inch OAL but do to the braces we have to deal with, I think alot of people want a shorter barrel to further take advantage of having a smaller rifle (pistol)

 

[Shemp]

12.3" per my calculations

13.7"

Also since it's usually only SoF that uses suppressors they probably dont give a fuck about having to rebuild them after every outing since 10.3" is just absolutely pummeling that blast baffle

 

[Shemp]

In a perfect world without NFA and SBR, I believe a lot of folks would go with a 14 inch OAL but do to the braces we have to deal with, I think alot of people want a shorter barrel to further take advantage of having a smaller rifle (pistol)

I would run 14.5" all day if not a 20"

 

[AC-130 Above]

I would run 14.5" all day if not a 20"

I want a 50” now

 

[AC-130 Above]

50” me

 

[mark23]

I want a 50” now

That's probably ideal. It would fragment before leaving the barrel.

 

[Shemp]

@Jds556762

 

[AC-130 Above]

Side note: you know you didn’t get much sleep last night when you wake up and remember a dream you had of buying a Izzy SKS from Stanley off The Office

 

[AC-130 Above]

That's probably ideal. It would fragment before leaving the barrel.

Just wanna reach out and touch someone

 

[Augustatrader]

So, is part of the "new norm" that USPS shipping will be even shittier and less reliable?

 

[AC-130 Above]

Screenshotted this yesterday I need dis

 

[Mr. Goodbar]

Screenshotted this yesterday I need dis View attachment 88752

300 blk out if you want short in ar style

 

[AC-130 Above]

300 blk out if you want short in ar style

But that means I gotta buy the spensive ass 300 Whisper rounds

 

[AC-130 Above]

Accuracy isn’t really a big concern. I just need a big ass fire ball. I just shoot clean over their heads, more of a deterrent

 

[Axeman]

Never thought about over penetration. Interesting. So 77 grain 5.56 is optimal when trying to reduce/eliminate over penetration? Along with a longer pistol barrel

In a perfect world without NFA and SBR, I believe a lot of folks would go with a 14 inch OAL but do to the braces we have to deal with, I think alot of people want a shorter barrel to further take advantage of having a smaller rifle (pistol)

Really it’s all about the PURPOSE.
If you want to do it like I do and EDC in a bag, 10.5 is your minimum, but there’s extra homework and mods to do to get it running right.
If you’re looking for best handling for HD, 12.5-14.5 is your range.
If fireballs and pissing off people at the range while punching holes in paper is your deal, then say “Fuck it all” and go 7.5” and enjoy the jams and maintenance issues.

Then there’s the ammo. Generally, 55gr works well enough out of longer barrels, At short-mid-range distances.
For reaching out a long way, you need a heavier, more stable bullet from a longer barrel. I’m not even gonna get into twist rate right now.

62gr is also very good at short to mid-range, and works better out of a shorter barrel than a 55gr will at short range. It’s sort of the compromise weight, and there are some in this class that work better than others. @Jds556762 knows all about it

77gr is your long-range load. Out of a short barrel it’s going to have problems getting enough speed and therefore energy to expand properly or fragment, but from a 16-20” barrel it works better at delivering to 500y+.

Good basic synopsis?