Problem - the shorter the barrel, the lower the velocity, and 5.56x45mm bullets' major wounding mechanism is yaw followed by violent fragmentation, which generally only occurs above a "magic velocity" of, if I remember right, around 2500 fps.
Below this velocity the bullet just enters, turns a bit, and that's it. Above it, you get horrific devastation, at least with a properly-designed all-lead bullet with a mid-bullet cannelure that forms a weak spot where the bullet can break (e.g. M193 or equivalent ammo).
When you have a short barrel like the one pictured, you're likely to never exceed 2500 fps at any useful distance from the barrel, so stopping power is severely reduced. Stick with 16-inch or better for 5.56x45mm weapons, and with the proper ammo type, to get extreme stopping power.
I'm not personally into the short barrels, so I never looked into what the best calibers/rounds are for them. So, I'm not the best guy to ask. Find a short-barrel fan and I'm sure they can suggest stuff.
Problem - the shorter the barrel, the lower the velocity, and 5.56x45mm bullets' major wounding mechanism is yaw followed by violent fragmentation, which generally only occurs above a "magic velocity" of, if I remember right, around 2500 fps.
Below this velocity the bullet just enters, turns a bit, and that's it. Above it, you get horrific devastation, at least with a properly-designed all-lead bullet with a mid-bullet cannelure that forms a weak spot where the bullet can break (e.g. M193 or equivalent ammo).
When you have a short barrel like the one pictured, you're likely to never exceed 2500 fps at any useful distance from the barrel, so stopping power is severely reduced. Stick with 16-inch or better for 5.56x45mm weapons, and with the proper ammo type, to get extreme stopping power.
References: see Martin Fackler, et al.
That’s why this is my 300 BLK. lol
Ha! My bad then!
lol. No worries bro. I have two AR rifles. One is 16 and the other is 18. I’m still going to build a 5.56 AR pistol though.
a muzzle for that 300 would be completion.
That’s why you have to buy rounds specifically engineered for ~10.5” barrels.
Would you please suggest an "Other" sbr-type proper config? What caliber would be useful or rather more so than 300 Blk or 556?
I'm not personally into the short barrels, so I never looked into what the best calibers/rounds are for them. So, I'm not the best guy to ask. Find a short-barrel fan and I'm sure they can suggest stuff.
thx
Your comment is close. But wrong. You are confusing and conflating several aspects together improperly.
Weight of the bullet, bullet shape and twist rate are what contribute to bullet tumble.
The thing you are trying to refer to, is bullet expansion. Which requires between 1900-2100fps to expand properly, depending on the brand ammo.
Also, a 10.5" barrel will most definitely see 2500fps, you should NOT go under 7-8" though.
Lastly, I know you're trying to help... but if he didn't want a 16" rifle, and wanted a 10.5" pistol, don't tell him his business.
Yeahhhhh, okay. I'm just not gonna get into rebutting all that. Have a nice day.