In order to participate in the GunBroker Member forums, you must be logged in with your GunBroker.com account. Click the sign-in button at the top right of the forums page to get connected.
Options

A few AR questions

rimfire72rimfire72 Member Posts: 901 ✭✭✭✭
edited February 2005 in Ask the Experts
I usually work with bolt actions,but I went to a show today and on a whim bought an AR stripped lower(DPMS). Figured I'd try my hand at building an AR target/varmint rifle. I've been doing some research and have a few questions.

1. Trigger selection.Opinions/experience with these triggers (or others).
Rock River National Match trigger
Jewell (I've used these in bolt actions,like them fairly well)
JP adjustable
2. Barrels. I'm looking at the 24" fluted bull bbls. I plan on using 50-60gr bullets. From my research I believe the 1 in 9" twist to be best for these weights. Opinions on twist rates and different brands(so far the Rock River looks about the best to me).
3. Chambering. .223 or 5.56. I know theres a slight difference in these,but how much? I'm assuming that if you have a .223 chamber and shoot mil 5.56 that accuracy will not be as good as with actual .223 and vice versa. I'm going to reload for accuracy so I'm probably going with .223 but might shoot milsurp sometimes just for cheap plinking.
4.Small parts. Is there a big advantage to titanium parts or are they an unneccessary expense?
Opinions?
I'll probably have more questions later. Thanks in advance.

buycoolshirts_1825_31216154.jpg
· Share on FacebookShare on Twitter

Comments

  • Options
    Red223Red223 Member Posts: 7,946
    edited November -1
    Congrats on getting an AR!

    1. Jewel Triggers, I have never had a rifle with one but all of my friends with tons of money say those triggers are sweet. If you can afford it, get it.

    2. Barrels/Chambering .....to heck with .223/5.56. Get a .300 Whisper kit and give us a range report.

    3. Titanium firing pins just sound tuff. Go for a chromed bolt carrier. The AR poops where it eats.





    http://quarterbore.com/300whisper/rifles/video_rig06.wmv
    · Share on FacebookShare on Twitter
  • Options
    richbugrichbug Member Posts: 3,650
    edited November -1
    If you go Rock River, they use a 223 wylde chamber which is designed to use both 556, and 223 rem ammo. I built an HBAR model last year with their 1in9 chrome moly, and have been happy with it.

    My border collie is smarter than your honor student.
    · Share on FacebookShare on Twitter
  • Options
    Vortech347Vortech347 Member Posts: 79 ✭✭
    edited November -1
    I've done a lot of reading lately on AR's as I am building one myself. From what I have read you can shoot either .223 or 5.56 if you have a 5.56 chamber. You are taking a risk shooting 5.56 in a .223 chamber. The 5.56 chamber specifies a longer throat than the .223 chamber.

    The .223 Wylde is supposed to be a compromise between the 2 chamber specs which allows you to shoot either ammo and still retain good accuracy with .223 ammo and still be safe with 5.56 ammo.

    For a varmint upper Rock River uses the Wylde chamber so you should be fine.

    I am going to build an M4 clone first with a 5.56 chamber. I intend to build a varmint type upper later and will probably go Rock River with the Wylde chamber.

    I am goint to use the Rock River two stage trigger as well but only because it has been recommended by a local gunsmith and from reading on AR15.com. I have zero experience with anything other than factory triggers on AR type guns and think the factory triggers are junk.

    There is a very good writeup on twist rates on AR15.com. 1:9 sounds like a good twist rate for what you want to do. If you decide to go heavier in the 70 grain range you will need a 1:8 or 1:7.
    · Share on FacebookShare on Twitter
  • Options
    KEVD18KEVD18 Member Posts: 15,037
    edited November -1
    in addition to the longer throat, 5.56m is loaded to produce a higher chamber pressure. can be risky to shoot 5.56 in a .223 chamber

    (pirated from another forum)

    With the appearance of full metal jacket military 5.56 ammunition on the commercial Market, it has come to the attention of the Sporting Arms and Ammunition Manufacturers' Institute (SAAMI) that the use of military 5.56mm ammunition in sporting rifles chambered for Caliber .223 Remington cartridges can lead to higher-than-normal chamber pressures and possible hazards for the firearm, its user and bystanders.

    Tests have confirmed that chamber pressures in a sporting rifle may be significantly higher in the same gun when using military 5.56mm ammunition rather than commercially loaded Caliber .223 Remington cartridges, according to SAAMI.

    SAAMI points out that chambers for military rifles have a different throat configuration than chambers for sporting firearms which, together with the full metal jacket of the military projectile, may account for the higher pressures which result when military ammunition is fired in a sporting chamber.

    SAAMI recommends that a firearm be fired only with the cartridge for which it is specifically chambered by the manufacturer
    With the appearance of full metal jacket military 5.56 ammunition on the commercial Market, it has come to the attention of the Sporting Arms and Ammunition Manufacturers' Institute (SAAMI) that the use of military 5.56mm ammunition in sporting rifles chambered for Caliber .223 Remington cartridges can lead to higher-than-normal chamber pressures and possible hazards for the firearm, its user and bystanders.

    Tests have confirmed that chamber pressures in a sporting rifle may be significantly higher in the same gun when using military 5.56mm ammunition rather than commercially loaded Caliber .223 Remington cartridges, according to SAAMI.

    SAAMI points out that chambers for military rifles have a different throat configuration than chambers for sporting firearms which, together with the full metal jacket of the military projectile, may account for the higher pressures which result when military ammunition is fired in a sporting chamber.

    SAAMI recommends that a firearm be fired only with the cartridge for which it is specifically chambered by the manufacturer.

    defiantley got with a nm 2 stage trigger. worth the money

    MAEMTPATCH.jpgFord_E350_ambulance1.jpgemt2.jpg

    Air goes in and out, blood goes round and round, any variation on this is a bad thing.
    Turret mounted machine guns usually work better than lights and sirens
    · Share on FacebookShare on Twitter
  • Options
    allechalleyallechalley Member Posts: 888 ✭✭✭✭
    edited November -1
    Some of the decision on trigger depends on if you want a single stage or two stage trigger. The Jewell, I think,is two stage, the JP is
    single stage. The JP is a little tougher and fussy to put in, not sure on the Jard, but the Jard and JP usually are sold without the speed hammer wheresas the Jewell is complete. Also, check out the Wilson trigger now available. Most of these can be found at www.midwayusa.com and descriptions. They all are a great improvement over stock, they just have different features, advantages,ect.
    · Share on FacebookShare on Twitter
  • Options
    MooseyardMooseyard Member Posts: 2,541 ✭✭✭✭✭
    edited November -1
    I just tried a new JP drop-in trigger this weekend, and it is one of the best triggers I have ever tried. I'm also sending JP a lower, so they can put one of their adjustable triggers in. I had a RRA trigger, and I wasn't impressed, but I have a friend who has one, and it is very good. I also have a Chip McCormick which is good, but I'm going to repalce it with a JP.

    "My faith, my country and my family will guide me; nothing more, nothing less" -Gen. Tommy Franks

    Jess Hoffman
    Mooseyard Precision
    LE Supply & Firearms
    NRA Certified Instructor
    Shawano, WI 54166
    · Share on FacebookShare on Twitter
Sign In or Register to comment.