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Posted: 6/4/2008 7:52:41 PM EDT
| How far out is 6.8 effective if you use a 16” barrel with 1/10 twist? I know it also depend on the ammo but I sure someone will tell me that with the distance. |
You are not very clear with what you mean. What type of target? Human or not? Do you mean when the OTM bullet will no longer fragment? Do you mean when a Soft Point, or TSX, bullet will no longer expand? Do you mean when the bullet will go into the transonic range? Do you mean when the KE of the round is too low to penetrate soft tissue? |
I done told you point target effective range. Yes, the 800 yard range is from my experience and knowledge. Hollywood USMC S/S Instructors were shooting 4 1/2" groups @ 800 yards from Stewart modified AR-10s with 175gr fodder starting out slower than 2550fps... yeah, 110-120gr @ 2700-2800fps at 800yds of 6.8 is going to make someone late. |
Yes, but this is mostly a function of operator skill. The M-855 ammo is lethal to a much longer distance than 550 meters. A 16" Barrel 6.8 has more KE than a M-16A2/A2 at any reasonable range. Please read the 6.8 Upper Evaluation Thread. |
Look at the post time you posted at 9:01:24 and I posted at 9:02:52. I was typing while you were answering the question. I didn't post this after I read you're post. |
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I suppose one way to look at it is to have a minimum energy and velocity requirement. I have a 30 carbine that falls to just a couple hundred foot pounds energy at 300 yards. not really enough for deer or game, with about the same energy as a 22LR at short range. Sure, up close it is much better, My best guess is anything less than 1000 Lb/ft is too low for reliable deer hunting at extended range. Sure a 22 will do it with a well placed shot, but what if the shot is not pinpoint accurate. |
| I have that same set up that you asked about(I also had my barrel cryo'd)with OTM loads.....I can hit water jugs, bowling pins, etc. at 585yrds....that being said, with 1/10 twist you wont be able to shoot the SSA extreme, so your going subsonic right around 600yrds....at that range your drop starts getting rediculous(really you start getting dramatic drop after 400-450 yrds). Also most people(myself included) are using midrange optics 1x4 or 1.5x5 at 600yrds the 5x is about at it limit for any type of percision shooting. So to answer your question 600yrds.....but the drop and optics are going to be your main factor. Hope this helps. |
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Dont be so sure of what the 1/10 SAMMI chambwe will not do. I have 2 Ko-Tonics and one Bushy w/ the dreaded 1/10 SAMMI chamber. I can push SSA brass, CCI 41 primer, 28.5gr H322, 115gr SMK w/ OAL of 2.25. Mine will shoot Art's combat loads all day. Please do not think I like the SAMMI chamber. I dont. Thank God for those who have a clue (obviouslt not Remmington) and for Tim at Cardinal Armory. I use my SAMMI as my beater and load developer. |
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