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people really misunderstand 5.56 ballistics out of short barrels. It’s true that something like a 7.5” fairly anemic, but those next 3-4” to 10.5 or 11.5 are some of the biggest velocity gains, proportionately, that you’ll find in the world of barrel lengths and projectile speed. You go from about [email protected] 7.5”, to around 2700-2800 at 10.5 like you said, and then 11.5” will get you another 100fps or so. Considering that the trade off from a much longer barrel that is basically unusable in cars and much more difficult indoors is only a few hundred feet per second less than the absolute high end you’re going to achieve of 3200fps with a 20” barrel, or more like 3000-3050 with a 16” which is what most people have, I’d say the shorter barrel is WELL worth the trade. Especially since we all presumably have m1a’s slung over our backs while using these little baby AR’s, eh? 😂
You’re exactly right. I thought the 10.5 or other pistol lengths were just a range toy for making noise. After my best friend convinced me to order a kit (at the time a whopping $280 shipped) I realized that you still get 90% of the performance with a gun dang near half the size.

Its since become my go to AR.
 

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Discussion Starter · #22 ·
I don't think suppressors are adding to velocity like extra barrel length does. Double check that thought.
Not to the same extent, no, but they are inherently giving the bullet more time in front of expanding gases in a tight tube. You are right that a 7.5” barrel + a 10” silencer doesn’t = 17.5” barrels worth of velocity. But it will be a higher velocity than the 7.5 barrel sans suppressor
 

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Discussion Starter · #23 ·
Thanks for sharing. Looking forwards to seeing your debut with the little tickler.
I mean that in a funny way .... 5.56 ain't no joke. I love the 77gr pills.

Nice post count BTW. I hope you stick around so we can continue to get to know you and vise versa.
Excellent bunch of guys here.
That really means a lot, man. And I do plan to stick around. I like this community. Thank you, sincerely.
 

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Not to the same extent, no, but they are inherently giving the bullet more time in front of expanding gases in a tight tube. You are right that a 7.5” barrel + a 10” silencer doesn’t = 17.5” barrels worth of velocity. But it will be a higher velocity than the 7.5 barrel sans suppressor
If the bore in the suppressor is larger than the barrel and there are all the various ports and chambers then pressure really goes to zero and shouldn't be contributing to flight of the projectile. So the velocity shouldn't be greater than if without the suppressor as the remaining expanding gases can't keep pushing effectively. But I concede if it like a gentle push on the ens that doesn't upset the stability than I could be convinced otherwise.

Now has any body on here measured this by chance? I know precision shooters still use cans but the short range guys aren't depending on accuracy losses and increases in velocity by using them.
 

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Discussion Starter · #25 ·
If the bore in the suppressor is larger than the barrel and there are all the various ports and chambers then pressure really goes to zero and shouldn't be contributing to flight of the projectile. So the velocity shouldn't be greater than if without the suppressor as the remaining expanding gases can't keep pushing effectively. But I concede if it like a gentle push on the ens that doesn't upset the stability than I could be convinced otherwise.

Now has any body on here measured this by chance? I know precision shooters still use cans but the short range guys aren't depending on accuracy losses and increases in velocity by using them.
I’ve got only anecdotes, but again, I’m not trying to overstate this effect, only trying to say that it’s enough to be significant at longer ranges to matter. This is what I’ve been told by people I trust and who have proven to have great knowledge on related subjects,
Experience professionally, etc. but I concede I can’t say I have seen the effect firsthand and could be wrong
 

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Discussion Starter · #26 ·
Also as an update I’ve got it dead on at 25 yards. Or as dead on as you can be without a sandbag and all that stuff, just seated with the rifle on the bench and me holding on tight. Groups are about an inch and a half with either optic, no doubt due to my inadvertent slight swaying. But nevertheless when I don’t sway i can see it’s dead on. Time to try 100!
 

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Discussion Starter · #28 ·
Does the Eotech have just a single red dot or is there a reticle with different aiming points?
They call it the “donut of death”, it’s a 68 MOA circle with a 1 moa dot in the middle. The idea is to zero it at 50 yards w the dot, and then the hash mark on the bottom of the circle is dead on at 7 yards. The effect is still quite similar with a 25/300 zero.
 

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They call it the “donut of death”, it’s a 68 MOA circle with a 1 moa dot in the middle. The idea is to zero it at 50 yards w the dot, and then the hash mark on the bottom of the circle is dead on at 7 yards. The effect is still quite similar with a 25/300 zero.
I have an AR536 with a circle of death. But it has drop compensated aiming points I like. But one needs to really check where you are hitting depending on your ammo and barrel length.
Font Material property Parallel Circle Number
 

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Also as an update I’ve got it dead on at 25 yards. Or as dead on as you can be without a sandbag and all that stuff, just seated with the rifle on the bench and me holding on tight. Groups are about an inch and a half with either optic, no doubt due to my inadvertent slight swaying. But nevertheless when I don’t sway i can see it’s dead on. Time to try 100!
Pistol. Never know who is watching..
 

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Discussion Starter · #38 ·
Pistol. Never know who is watching..
Sorry, I was shooting the socom interchangeably so I could use the 6x scope to see my shots, honest mistake. That being said, the same way shouldering a pistol doesn’t change it to a rifle, does accidentally calling it a rifle change it to one? Again I was bench shooting a pistol like you would any pistol you wanted to properly zero, and the socom was right next to me and being picked up and stared through often. Slip of the tongue.
 

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Discussion Starter · #39 ·
Anyways, shoot it at 100 was complicated, or more than it initially seemed. The grouping wasn’t bad but wasn’t where I expected. Where I messed up, arguably (if the whole thing wasn’t a mess up) was trying to zero at 45 degrees without considering that down is no longer down, right no longer right, etc. I somehow got a mag fairly well on the man sized targets neck and upper chest while aiming for the heart, and then changed the zero, and then was totally off the target. That’s when I realized I was essentially trying to put a 100yd zero on it, and should have just held differently, but, wouldn’t you know it, I couldn’t see the target impacts. Need a spotting scope or something. I had it pretty good at 25 but as I thought about it, at a 45 degree angle you can’t even use the bullet drop reticle which is precisely what you’d want on an optic meant for longer shots so. It just an EOtech again. Ah well. Gotta try stuff sometimes.
 

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The barrel is just a tube. It doesn't care how it's held. As long as you are holding gun in the same plane as the optic and there is now weird offset like on a Garand, up down right left are still relevant. Now if your 45° hold is actually 30° or 60°, that's a different issue.
 
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