Maximun effective range of a SBR AR

beenjammin

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I was considering SBRing my FN SCAR 16s, but wondered how it would effect my accuracy at say out to 300 yards/meters. This is about the max range I would use this weapon. I would like it shorter, but not at the cost of losing range. SBRing to 14.5" is not worth it so I would go 11" prob.

If I could make it lighter, shorter and retain 300 yard accuracy Id do it. Otherwise why even bother.

BTW: the SBR law in AL just passed and I have never had one before so I really have limited experience with a SBR.
 

Texas_Archer

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Re: Maximun effective range of a SBR AR

Accuracy. Has nothing to do with barrel length. You will be giving up velocity. Just pick good bullets.
 

beenjammin

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Re: Maximun effective range of a SBR AR

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Texas_Archer</div><div class="ubbcode-body">Accuracy. Has nothing to do with barrel length. You will be giving up velocity. Just pick good bullets. </div></div>


Thanks for the help. The SCAR is really quite accurate at 100 with iron sights using field quality ammo. When you say pick good bullets.. for this type of rifle? I was hoping to not have to be too picky.
 

alpha6164

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Re: Maximun effective range of a SBR AR

As others have said, accuracy and actually having an effective terminal performance are two different things. You wont have any problems "hitting" your target at 300yards with an SBR but not too many ammo options will give you any terminal performance at that distance. A 5.56 pressure 55gr bullet comes out of a 10.5" barrel at ~2750ft/sec. Since it is kind of accepted that 2700ft/sec is the lower threshold for 55gr fragmentation, then your effective range is about 25-30yards which is just fine for indoor stuff. If you step up to the 75-77gr variety, your range does extend to about 70-80yards since the fragmentation threshold is lower for the heavier bullets. At 300yards? you will make just tiny .22 caliber holes and maybe some tumbling once it hits tissue. But an SBR overall is the opposite spectrum of "optimum" for >100yard effectiveness.
 

rth1800

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  • Sep 16, 2009
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    Re: Maximun effective range of a SBR AR

    I had a similar post the other day and got quite a few responses. It was a bit mis-interpted as to my intent, but most of the people who favor SBR's are one of three types.
    MIL/LE guys who actually kick in doors.
    Wanna be's who dream of kicking in doors.
    People who realize they have no use for them.
    If you cannot defend your home with a standard M4 or 1911 you live in a very tough neighborhood or are just pitiful. A 16" M4 or even 20" is superior in most every way for everyday use.

    The reasons given for the SBR on my thread were on the order of "because I can" "chicks dig it" "b/c they are so cool" and "WTF business is it of yours?" Not exactly the ballistic facts I was looking for.
    I can say that I would suppress if shorter than 16 and even my 16 are never shot w/o suppressor in place. I just do not like the noise.

    Before anyone jumps on this post, realize that I am in no way suggesting that you not have exactly the AR you want. I personally do not see a need for one of less than 16. Get a 2" one if that is the length of tool you are accustom to working with. SMILE
     

    beenjammin

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    Re: Maximun effective range of a SBR AR

    I want an SBR becuase I want to run it suppressed and not have a super long barrel.

    Folded up the SCAR in SBR formation is such a tiny package.

    Where would the sweet spot be on barrel length to maximize compact size and 100-300 yard effectiveness.

    14.5?
     

    rth1800

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    Re: Maximun effective range of a SBR AR

    I do not know from expirence, but would think 12.5 or 14.5 would work. I doubt 14.5 is worth the effort, as so little would be gained over the 16", and would likely go with the 12.5. I have read, but do not know from expirence that the 12.5" AR's are bad to burn out some suppressors. You might want to choose a tough one or do some research. JMO
    You might want to try a 16 with a short suppressor. I use mine daily and never find it a problem. It shoots and kills well to 600 yards.
     

    Jer

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    Re: Maximun effective range of a SBR AR

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: rth1800</div><div class="ubbcode-body">I do not know from expirence, but would think 12.5 or 14.5 would work. I doubt 14.5 is worth the effort, as so little would be gained over the 16", and would likely go with the 12.5. I have read, but do not know from expirence that <span style="font-weight: bold">the 12.5" AR's are bad to burn out some suppressors</span>. You might want to choose a tough one or do some research. JMO
    You might want to try a 16 with a short suppressor. I use mine daily and never find it a problem. It shoots and kills well to 600 yards. </div></div>

    Uhm... no.
     

    nefarious79

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    Re: Maximun effective range of a SBR AR

    The thing with a 10.5 or 11.5 barrels on AR's is bullet fragmentation..I believe its only about 50yds with those barrels lengths. Thats will ball ammo, you should be gtg though if you plan on using TAP.
     

    bm11

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    Re: Maximun effective range of a SBR AR

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: beenjammin</div><div class="ubbcode-body">I was considering SBRing my FN SCAR 16s, but wondered how it would effect my accuracy at say out to 300 yards/meters. This is about the max range I would use this weapon. I would like it shorter, but not at the cost of losing range. SBRing to 14.5" is not worth it so I would go 11" prob.

    If I could make it lighter, shorter and retain 300 yard accuracy Id do it. Otherwise why even bother.

    BTW: the SBR law in AL just passed and I have never had one before so I really have limited experience with a SBR. </div></div>I've been down this same road with my SCAR, keep in mind that if you flake the chrome in your barrel cutting it, that you are out of luck for getting a replacement, at least for quite some time. I seem to recall 200 yards as being the maximum effective range for 5.56 with a 11 inch or so barrel, but I'm sure you can make hits well beyond that, it's just going to be a matter of how much energy you'll still be carrying.