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slimjim Super Member
Joined: May 16, 2009 Posts: 8314 Location: Fort Worth TX
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Posted: Mon Jul 26, 2010 5:28 pm Post subject: Re: What if...for slimjim by request, or anyone else, feel free. |
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fnuser wrote: |
Did you recognise what kind of magazine he was using? |
It looks like a MagPul though it may not be their latest version.
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slimjim Super Member
Joined: May 16, 2009 Posts: 8314 Location: Fort Worth TX
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Posted: Tue Aug 03, 2010 8:48 pm Post subject: Re: What if...for slimjim by request, or anyone else, feel free. |
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fnuser, how is the project going? I think I may call Mike at Dedicated technologies and talk with him about his 6mm DTI Wildcat based of the 6.8 case. He said via eamil that he would sell me just a barrel. I'd like to talk with him and see what initial load data he has and discuss the merits of this wildcat in 6.5mm. Let me know what you think.
Mike Milli
Dedicated Technology
(218) 444-7419
www.dtechsuperstore.co...mation.htm
_________________ "To anger a conservative, lie to him. To anger a liberal, tell him the truth." - Theodore Roosevelt
"The world is a dangerous place to live; not because of the people who are evil, but because of the people who don't do anything about it." - Albert Einstein |
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slimjim Super Member
Joined: May 16, 2009 Posts: 8314 Location: Fort Worth TX
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Posted: Tue Aug 03, 2010 9:14 pm Post subject: Re: What if...for slimjim by request, or anyone else, feel free. |
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I've been eyeing one of these for my upper.
www.alexanderarms.com/...=2&item=80
I think the side charge handle is an interesting option.
_________________ "To anger a conservative, lie to him. To anger a liberal, tell him the truth." - Theodore Roosevelt
"The world is a dangerous place to live; not because of the people who are evil, but because of the people who don't do anything about it." - Albert Einstein |
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fnuser Super Member
Joined: Dec 23, 2008 Posts: 914 Location: S.W. Missouri, U.S.A.
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Posted: Wed Aug 04, 2010 11:45 am Post subject: Re: What if...for slimjim by request, or anyone else, feel free. |
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what about that other upper you showed me that the side handle was independent of the carrier?
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slimjim Super Member
Joined: May 16, 2009 Posts: 8314 Location: Fort Worth TX
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Posted: Wed Aug 04, 2010 7:20 pm Post subject: Re: What if...for slimjim by request, or anyone else, feel free. |
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There is merit to their design. I just don't feel like its as beefy as the one from Alexander. Maybe I should look into it more and also find out the price.
_________________ "To anger a conservative, lie to him. To anger a liberal, tell him the truth." - Theodore Roosevelt
"The world is a dangerous place to live; not because of the people who are evil, but because of the people who don't do anything about it." - Albert Einstein |
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slimjim Super Member
Joined: May 16, 2009 Posts: 8314 Location: Fort Worth TX
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Posted: Wed Aug 04, 2010 8:28 pm Post subject: Re: What if...for slimjim by request, or anyone else, feel free. |
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found some more products of interest.
www.ar15performance.co...ng_6mmbrs_
I like this!
"The 6mm BRX shooting 105 Bergers or 107 SMKs will produce the best exterior ballistics from the AR15 platform. These uppers could be used for highpower or sniper type competitions, hunting or Varmint shooting. The 6BRX is pushing 105gr Bergers to 3000fps from a 22" barrel, making it the flattest shooting cartridge to fit a normal AR15. "
_________________ "To anger a conservative, lie to him. To anger a liberal, tell him the truth." - Theodore Roosevelt
"The world is a dangerous place to live; not because of the people who are evil, but because of the people who don't do anything about it." - Albert Einstein |
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slimjim Super Member
Joined: May 16, 2009 Posts: 8314 Location: Fort Worth TX
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Posted: Sat Aug 14, 2010 7:15 am Post subject: Re: What if...for slimjim by request, or anyone else, feel free. |
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ok, fnuser. Guess you have been on holiday (did I say that correctly, Vince?). I'm getting more serious about the performance potential of the 6mmBR case. I am pondering going to
6mmBRX (which moves the shoulder 0.1 inches forward by fireforming),
6.5mm BR (which you only have to neck-size up), or
6.5mm BRX (both of above)
The case is very efficient and you can pretty much get close to the performance of a .260 or or 6.5mm-.284.
what say thou?
_________________ "To anger a conservative, lie to him. To anger a liberal, tell him the truth." - Theodore Roosevelt
"The world is a dangerous place to live; not because of the people who are evil, but because of the people who don't do anything about it." - Albert Einstein |
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slimjim Super Member
Joined: May 16, 2009 Posts: 8314 Location: Fort Worth TX
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Posted: Sat Aug 14, 2010 7:19 am Post subject: Re: What if...for slimjim by request, or anyone else, feel free. |
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this site shows the differences between cases.
www.6mmbr.com/cartridg...grams.html
_________________ "To anger a conservative, lie to him. To anger a liberal, tell him the truth." - Theodore Roosevelt
"The world is a dangerous place to live; not because of the people who are evil, but because of the people who don't do anything about it." - Albert Einstein |
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fnuser Super Member
Joined: Dec 23, 2008 Posts: 914 Location: S.W. Missouri, U.S.A.
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Posted: Sun Aug 15, 2010 5:28 pm Post subject: Re: What if...for slimjim by request, or anyone else, feel free. |
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I saw that too, am leaning toward the 6.7 but the .308 bolt face you showed me at ar15performance has peaked my interest because i always wanted a 6mmbr or family member trying to figure out which mag they are using i may need to read that again
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slimjim Super Member
Joined: May 16, 2009 Posts: 8314 Location: Fort Worth TX
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Posted: Mon Aug 16, 2010 5:10 am Post subject: Re: What if...for slimjim by request, or anyone else, feel free. |
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_________________ "To anger a conservative, lie to him. To anger a liberal, tell him the truth." - Theodore Roosevelt
"The world is a dangerous place to live; not because of the people who are evil, but because of the people who don't do anything about it." - Albert Einstein |
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slimjim Super Member
Joined: May 16, 2009 Posts: 8314 Location: Fort Worth TX
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Posted: Mon Aug 16, 2010 5:48 am Post subject: Re: What if...for slimjim by request, or anyone else, feel free. |
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I've been leaning toward a 6.5mm because I want to be able to shoot at longer range. As part of my analysis, I look at several variables. IMO, if a cartridge can't achieve at least 3000 fps with lighter bullets for that caliber, its not an efficient case-bullet match for my application. Initially, I was excited about the 6.5 Grendel. However, after analysis I didn't move forward and kept investigating options. Below is the analysis I did. Yes it had better long-range performance than the .223 and 6.8 SPC but when you looked at the trajectories, they weren't very flat at all.
_________________ "To anger a conservative, lie to him. To anger a liberal, tell him the truth." - Theodore Roosevelt
"The world is a dangerous place to live; not because of the people who are evil, but because of the people who don't do anything about it." - Albert Einstein |
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slimjim Super Member
Joined: May 16, 2009 Posts: 8314 Location: Fort Worth TX
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Posted: Mon Aug 16, 2010 5:54 am Post subject: Re: What if...for slimjim by request, or anyone else, feel free. |
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You can see that the 6.8mm bullets are light for the .277 caliber and don't have very good BC for longer range application. They do good, however, for short barrel, short-to-medium range AR applicaitons. The 6.5 Grendel has better bullets BC-wise but the muzzle velocities are too low resulting in arcing trajectories.
_________________ "To anger a conservative, lie to him. To anger a liberal, tell him the truth." - Theodore Roosevelt
"The world is a dangerous place to live; not because of the people who are evil, but because of the people who don't do anything about it." - Albert Einstein |
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fnuser Super Member
Joined: Dec 23, 2008 Posts: 914 Location: S.W. Missouri, U.S.A.
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Posted: Mon Aug 16, 2010 1:31 pm Post subject: Re: What if...for slimjim by request, or anyone else, feel free. |
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It looks like the 6.8 110 g. is a nice performer what we don't see in this chart are the resulting velocities at various ranges and this is where the b.c. really pays off as in the formula for energy the velocity is a bigger factor then bullet weight but I still like the 6.8 over the 6.5 for the ability to use standard mags with a slight mod not possible w the 6.5 also the resulting trajectories will be within a vitals area of each other at normal hunting ranges below 300 yrds. so that is a wash. I'm not saying the 6.8 is the end all do all cartridge, heaven forbid, We need to save excuses for the next project. I am still thinking the 6mmbr for that but I bet the mags are a major pain in the back pocket for those. I have a long barreled .280 ackley w a 1-8 twist barrel that I have chronied the velocity at 2900 fps w 180 bergers go crank that through a ballistics chart if you like looking at numbers its an awesome cartridge. and a pretty package also if you like o.d. green manners stocks.
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slimjim Super Member
Joined: May 16, 2009 Posts: 8314 Location: Fort Worth TX
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Posted: Mon Aug 16, 2010 5:05 pm Post subject: Re: What if...for slimjim by request, or anyone else, feel free. |
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fnuser wrote: |
It looks like the 6.8 110 g. is a nice performer ... |
Now that the 6.8 SPC is gaining in popularity, they bullet manufacturers are coming out with more light-weight .277 bullets. The 110 Barnes TSX takes up too much powder capacity with a resultant drop in velocity. Barnes now has an 85gr all-copper bullet. After reloading and shooting the .270 for a couple of years, I have a hard time appreciating the 6.8 SPC unless you compare it to short-barreled 5.56s. 6.8/.227 bullets just don't have high enough BCs to go the distance very well as the graph shows.
Last edited by slimjim on Mon Aug 16, 2010 5:08 pm; edited 1 time in total |
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slimjim Super Member
Joined: May 16, 2009 Posts: 8314 Location: Fort Worth TX
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Posted: Mon Aug 16, 2010 5:06 pm Post subject: Re: What if...for slimjim by request, or anyone else, feel free. |
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fnuser wrote: |
what we don't see in this chart are the resulting velocities at various ranges ... |
I only show the velocity at 1000 yards just because that is my long-range shooting objective for this next rifle. I think I should see if I can introduce trajectory drop an wind drift into the chart.
_________________ "To anger a conservative, lie to him. To anger a liberal, tell him the truth." - Theodore Roosevelt
"The world is a dangerous place to live; not because of the people who are evil, but because of the people who don't do anything about it." - Albert Einstein |
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