Anyone here into firearms?

Ghostvette · 07-14-2014, 08:33 AM

Quote:

Originally Posted by synolimit

I've seen tons and tons of ar500 videos and almost nothing penetrates it. Yesterday we were shooting at a 6x8 1/4" plate you can get off ebay for a plate carrier. We shot 8mm Mauser 196gr from a 1944 Mauser 24.5", .308 150gr from a Springfield m1a 18", every 5.56mm you can think of including green tip from 10" to 18" barrels etc. not even more than a few dings.

A guy comes along and punches right through it 5 times with a ar15 like it was nothing! I ask him what ammo he used and he just said normal 55gr FMJ!! But he says with his 24" barrel they're doing 3700fps. Was this guy telling the truth? I get more velocity is better but even a normal 55gr round at that speed I'd think ar500 would stop it. Any thoughts or calculators out there to guess his kinetic energy when a .308 m1a wouldn't even scratch it? Was he lying? Using AP rounds?

I call BS. The longer barrel won't increase muzzle velocity, that is a function of the powder that is burned. At that speed, that bullet would come apart on impact, not penetrate. The chamber pressure required to generate that velocity would exceed SAAMI specifications and the gun isn't long for this world. My guess is steel-cored 5.56, since it defeats most armor out there. That's my

synolimit · 07-14-2014, 09:24 AM

Quote:

Originally Posted by Ghostvette

I call BS. The longer barrel won't increase muzzle velocity, that is a function of the powder that is burned. At that speed, that bullet would come apart on impact, not penetrate. The chamber pressure required to generate that velocity would exceed SAAMI specifications and the gun isn't long for this world. My guess is steel-cored 5.56, since it defeats most armor out there. That's my

Actually we figured it out on ar15.com. The bullets traveling fast enough and the time it takes for the bullet to hit the plate from start to finish is more powerful then the slower .308 or 8mm Mauser. Like hitting a nail with a hammer vs pushing on the nail with a rock and all your weight. You can get more power with a rock and weight but at a longer time with no penetration. At 3700fps the little 5.56 is actually going fast enough it's exceeding the breaking point of the steel. We can see this from the ar500 actually chipping at the very tip where the round entered.

And I'm not sure where you heard barrel length doesn't increase velocity but that's false. Every inch in a 5.56 is about 200fps. My 10" barrel shooting the same rounds is over 1000fps slower vs his 24".

Ghostvette · 07-14-2014, 11:07 AM

Quote:

Originally Posted by synolimit

Actually we figured it out on ar15.com. The bullets traveling fast enough and the time it takes for the bullet to hit the plate from start to finish is more powerful then the slower .308 or 8mm Mauser. Like hitting a nail with a hammer vs pushing on the nail with a rock and all your weight. You can get more power with a rock and weight but at a longer time with no penetration. At 3700fps the little 5.56 is actually going fast enough it's exceeding the breaking point of the steel. We can see this from the ar500 actually chipping at the very tip where the round entered.

And I'm not sure where you heard barrel length doesn't increase velocity but that's false. Every inch in a 5.56 is about 200fps. My 10" barrel shooting the same rounds is over 1000fps slower vs his 24".

Interesting. Since most of my 5.56 platform guns are 16", muzzle velocity doesn't matter much to me. While the 5.56 will shoot to 600 yards, I don't see much need to shoot that range with that small of round. For 600 to 1000 yards, I prefer a .308 or .30-06 (again, personal opinion/preference). While muzzle velocity will increase to a point over a 10" barrel, there is a barrel length that you get max velocity, anything over that will actually cause a decrease. So maybe I was a little out of line saying 'BS' on the m.v. claim. Unless you were shooting over a chronograph to get an accurate reading on velocity, someone saying his muzzle velocity is xxxx, I tend to be a little skeptical. That's just me. I'm more of an accuracy guy, I load to what gives me the best performance out of my gun at the range I want to use it for. For what it's worth, I just looked at Federal's website for their ammunition. It shows that a 55 grain boat tail is driven at 3240 fps. They show 3700 fps with a 40 grain Nosler Ballistic Tip.

I definitely don't want to get into a disagreement over m.v. on a 5.56, or what it does to body armor. I've been around firearms for a long time, and I tend to be skeptical when someone claims a m.v. that sounds outrageous to me. It's great that there are Z owners that enjoy firearms and shooting, so on that note, I'll say no more about 5.56 m.v.

Wolfenstein · 07-14-2014, 11:25 AM

I've got a few guns myself....mostly pistols.

Kimber Stainless Pro Carry II 1911 .45
Kimber Ultra TLE II 1911 .45
Springfield A1 Loaded with all kinds of custom goodies 1911 .45
Glock 19 9mm
S&W Bodyguard .380
Ruger SR9C 9mm
Sig Sauer P229 Extreme 9mm (my favorite)

I also have a old .243 breach load (cant remember the name brand)
Mossberg 500 with a pistol grip

and some others which I cant remember off of the top of my head.

synolimit · 07-14-2014, 04:50 PM

actually i was wrong too with the 200fps per inch. but i just saw a guy cut a 24" barrel to 16.5" at every inch. the 24" was the fastest. like Hilters V-3 cannon you do get the fastest rounds out of the longest barrel. im sure a 5.56 will eventually slow but i dont think we'd know when, when most only go to 24". i believe him since most 24" barrels like the tester guy shot, was almost 3500fps out of a reminton 700 with a normal 5.56 55gr round. the guy that shot through the ar500 had a "bull something" barrel that was chrome lined or something, adding to the speed he said. he seemed to know his stuff so id guess he did 3700fps with a chronograph at some point.

regardless of m.v., at 50 yards he punched straight through it while none of us could.

Quote:

Originally Posted by Ghostvette

Interesting. Since most of my 5.56 platform guns are 16", muzzle velocity doesn't matter much to me. While the 5.56 will shoot to 600 yards, I don't see much need to shoot that range with that small of round. For 600 to 1000 yards, I prefer a .308 or .30-06 (again, personal opinion/preference). While muzzle velocity will increase to a point over a 10" barrel, there is a barrel length that you get max velocity, anything over that will actually cause a decrease. So maybe I was a little out of line saying 'BS' on the m.v. claim. Unless you were shooting over a chronograph to get an accurate reading on velocity, someone saying his muzzle velocity is xxxx, I tend to be a little skeptical. That's just me. I'm more of an accuracy guy, I load to what gives me the best performance out of my gun at the range I want to use it for. For what it's worth, I just looked at Federal's website for their ammunition. It shows that a 55 grain boat tail is driven at 3240 fps. They show 3700 fps with a 40 grain Nosler Ballistic Tip.

I definitely don't want to get into a disagreement over m.v. on a 5.56, or what it does to body armor. I've been around firearms for a long time, and I tend to be skeptical when someone claims a m.v. that sounds outrageous to me. It's great that there are Z owners that enjoy firearms and shooting, so on that note, I'll say no more about 5.56 m.v.

07-14-2014, 11:25 AM	#4 (permalink)
Wolfenstein Base Member Join Date: Jun 2013 Location: Cleveland Posts: 221 Drives: '13 Nismo \| '14 WRX Rep Power: 14	I've got a few guns myself....mostly pistols. Kimber Stainless Pro Carry II 1911 .45 Kimber Ultra TLE II 1911 .45 Springfield A1 Loaded with all kinds of custom goodies 1911 .45 Glock 19 9mm S&W Bodyguard .380 Ruger SR9C 9mm Sig Sauer P229 Extreme 9mm (my favorite) I also have a old .243 breach load (cant remember the name brand) Mossberg 500 with a pistol grip and some others which I cant remember off of the top of my head. __________________

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