Posted: 11/1/2005 7:01:12 PM EDT
|
I'm a young (22) pistol guy. I have a custom SA 1911 and a custom STI 2011 (Sorry to the Colt 1911 fans hinking.gif). I'm new to the rifle scene and a future AR buyer, and I want a Colt. No doubt. I'm still learning about the basics of the AR before I purchase, much like I did about 1911s before I had one built for me. But I have several questions about Colt's production line of ARs before I buy. 1) What is the difference between the LE6920 and the MT6400C? The only thing I can see is that the LE6920 has a flash suppressor, and the MT6400C has a compensator. Does the Compensator supress flash also? What is everyone's preference? 2) What is the difference in ammo selection and the rule for bullet weight with a 1in7 and 1in9 rate of twist? I saw where someone had said that a 55gr bullet is too light for a 1in7 twist because the twist was too fast. What is the theory behind the relationship of bullet weight to weight of twist? Also, a buddy was telling me that you can shoot a wider variety of bullet weights with a 1in9 twist. True? 3) If the above is true, a wider variety of bullets can be shot through a 1in9 twist, then wouldn't the AR6721 be a better choice over the LE6920 or MT6400C? The only difference I see with the AR6721 is the 1in9 rate of twist and the lack of the M203 ready barrel. Is there anything else that separates the AR6721 from the other two? I don't think I'm going to need the M203 anyways. 4) What is the benefit of chrome lined barrel? Do the Colt factory ARs come stock with a chrome lined barrel? I heard that it is hard to find a chrome lined barrel in 1in7 twist and that its not really necessary for that twist. True or False? 5) Since I'm more of a custom mutt gun lover, I was thinking of just building a custom AR from the ground up on a Colt lower and upper, selecting all the internals, barrel, forend, stock, etc. What is everyone's view on this idea? Are Colt parts just as good as anyone elses? Or should I start with a stock Colt and change out parts as I see fit? Anyone and everyone's views and opinions are greatly appreciated. Thank you in advance. If there are any 1911 fans out there here's a link to the start of my gun collection: img.photobucket.com/albums/v638/Esaych69/PA270021.jpg |
|
STI beats a Colt hands down for Comp use. 1. MT6400C has a non functional collisable stock ie BAN Sate legal. Comp does nothing to supress flash. these two are the only real differences between the two rifles. 2. 1/7 is the better twist for heaver bullets (72 grain and above). MY A2 gov profile shoots 55 just fine untill barrel gets rather warm. If all your going to shoot is 55 grain 1/7 or 1/9 makes no difference, both stablize the 55 bullet just fine. 1/9 will also shoot m855 ammo. I dont know on liteter bullets ie 40 grain varmit type in either the 1/7 or 1/9 as I never went less than 55. I like my 1/12 A1 barrel for 55 use. 3. 6721 has a hvy proflie barrel about 1/2 pound more barrel steel. look at the listed weights between the two on Colts web adress the difference is all in the barrel. 4) someone was blowing smoke up your ass on this one. mt6400c ar6721 and the le 6920 all have Chrome lined barrels and chambers. all other MT from colt are unlined. Chrom is more forgiving on cleaning, and corrosion there a snap to clean as copper does not stick real well to the barrel. 5) I would use a lower and upper from CMT/STAG there a hell of a lot cheaper and just as well made, plus there fire control pins are the right dia. Not all aftermarket triggers are made to colts larger pin dia. For me I would go STAG/CMT lower and upper reciver, lower parts kit 4 pos stock. Colt Bolt Bushmaster or colt barrel, and colt for the M4 handguards. My egde is blued 40 cal. Mine will feed factory ammo, but chokes on reloads loadded to the normal longer length found on double stack 40's. |
|
The MT6400 lacks a bayo lug, flash suppressor, and collapsible stock. The compensator supplied with the MT6400 works to reduce some flash. It is better than a plain muzzle, but I had my barrel threaded by ADCO and an A2 FS installed. Choose the 1/7 twist. As Gregory said, it is for heavy bullets. Use the 55s for blasting. Use 75s or 77s for home defense. Read the Ammo Oracle. I would first supply myself with a good LE6920, then build something later. On custom 1911s.....mine is a Colt, more appropriately called the Novak's Colt. It is a 70 series turned into a gem by the Novak shop. 
|
|
Thanks for the info. Gregory, does your Edge have any work done to it? Maybe try reloading to a slightly shorter length. So are you saying that you would build up a STAG/CMT rather than a Colt just based on the price? Which is the better quality? I'll be going with the 1in7 twist though. Sounds more practical and better for home defense. Only other reason for shooting is at some local IDPA or IPSC matches. Are the aftermarket triggers that do offer Colt's larger diameter fire control pin worth looking into? Or can I get a better trigger from a comapny that doesnt offer the larger diameters? BTW, what is the weight of trigger pull on a stock LE6921? Can you polish internal trigger parts and such on an AR to lighten and smoothen the pull, much like you can on a 1911? |
|
Long Answer: Do a search. I just typed a freakin 500 word explanation about most of this stuff to someone a few days ago, otherwise I'd go into it more. Sorry, its not your fault that I am lazy, but hey what can I say. Short Answer: Get a Colt. A 6920. ETA: m-4 feed ramps 1/7 quality control colt bolt "m-16" bolt carrier h-buffer m-4 handguards need I go on?...You will not get all of these features on any other rifle. |
Like what the other guys said the 1/7 twist is good to stabilize heavier bullets. If you prefer the 1/9 twist, you could recontour the 6721 barrel to govt profile (light under the handguards) to make it lighter. ADCO Firearms could do a high quality, quick job. There are other brands that sells 1/7 rifles such as LMT, KAC, Sabre Defence, Limited Edition Stag Arms and also others I didn't mention. Most Colts have 2-stage triggers same as military rifles. I have a 6721 lower with Magpul MIAD grip, Vltor CAR club foot modstock and I'm currently building my custom upper with a 1/7 twist, chromed lined, mid-length, midweight barrel profile (heavier than a govt but lighter than a HBAR profile), M4 feedramps, LaRue 9.0 FF rails, Colt M4 upper and Colt M16 BCG. Good luck. |
|
no work on the edge just a trigger job. If you want a great aftermarket trigger for the 6920 for use in matches look at the JP. It takes about an hour to install as you have to fit some parts. But you get a 3.5 or less pound trigger with no creep or overtravel when you are done. |