New barrel for my Bushmaster Carbine

[jdbell2004]

I want to upgrade the barrel on my rig, stick with .223/5.56. I considered a complete new upper receiver but it fits my budget a little better to just go with a new barrel. I want this to be my coyote gun, maybe praire dog too.

I want more accuracy than I am getting with my contour 16" with m203 cutouts. Looking to get just under 1MOA if possible. I'd like to go 20", but if I can get good results with a shorter barrel, I wouldn't mind staying 16" or going 18". Is anything larger than 16" even an option without changing anything else on the upper (ie. buffer assembly)?

I want to use my current upper and BCG if possible. I want a heavy barrel with a gas block. Can I use my old upper and BCG with a new barrel?

So far I believe I will need a take down wrench and a punch set. A new barrel, free float hand guards, gas block and gas tube (length dependent on the barrel length?).

Sorry for all the questions, I searched and couldn't come up with much. The search on this site never works well for me...

Thanks!

Jon

[jdbell2004]

bump. anyone?

[moose01]

For a nice barrel, I would check with White Oak Armament, PAc-Nor, Lilja, Noveske, BCM, a stainless barrel from CMMG, or even a Wilson SS barrel from Rock River, just depending on exactly what you're looking for. If you're on a real budget, ER Shaw offers SS barrels through Model1Sales, and while I've hear they're decent in the accuracy compartment, you'll get what you pay for. I've heard more than a few reports of the RRA varmint barrel with the 1:8 Wylde chamber keeping 5 rounds of quality match ammo under .5 inches at 100 yards.

Your BCG will work fine, but you'll either want to check the headspace on the bolt you have, or order a bolt with your barrel. I know WOA will sell a bolt already headspaced to the barrel they send.

Changing the barrel length won't be an issue at all. The only thing that would be a factor is the length of the gas system you choose, and that's remedied with a gas tube. You can play with the buffer weight after you figure out the length of barrel/gas system combo you want.

[tylerw02]

Longer length does not increase barrel accuracy. Usually, the opposite is true. Shorter barrels are stiffer, and thus there is less whip.

You can use your same upper receiver and BCG, but it may not be the best idea. The best idea would be to sell it as a complete group and buy another complete group to meet your needs.

1 MOA is very, very possible without having to go with a bull barrel. Honestly, your existing barrel may be capable of 1 MOA. One would need to know what the rest of your specs are. Other parts of the carbine lead to the overall accuracy of the system.

What trigger are you running? Trigger is one of the most important factors contributing to accuracy.

Do you currently have a free-float rail/rube? If not, floating your existing barrel may increase your accuracy.

Which buffer are you currently using?

What ammunition are you currently using? You cannot use cheap, low quality ammunition in a 20" bull bbl and expect it to be supremely accurate just because its a 20" heavy barrel. What ammunition types have you used in your existing carbine?

I think your lack of responses here have been because this cite is mostly aimed at "fighting guns" with maximum reliability and durability, rather than extreme accuracy. Most people don't want to devote much time trying to make their gun as accurate as possible because it can, at times, be detrimental to function.

[jdbell2004]

Longer length does not increase barrel accuracy. Usually, the opposite is true. Shorter barrels are stiffer, and thus there is less whip.

You can use your same upper receiver and BCG, but it may not be the best idea. The best idea would be to sell it as a complete group and buy another complete group to meet your needs.

1 MOA is very, very possible without having to go with a bull barrel. Honestly, your existing barrel may be capable of 1 MOA. One would need to know what the rest of your specs are. Other parts of the carbine lead to the overall accuracy of the system.

What trigger are you running? Trigger is one of the most important factors contributing to accuracy.

Do you currently have a free-float rail/rube? If not, floating your existing barrel may increase your accuracy.

Which buffer are you currently using?

What ammunition are you currently using? You cannot use cheap, low quality ammunition in a 20" bull bbl and expect it to be supremely accurate just because its a 20" heavy barrel. What ammunition types have you used in your existing carbine?

I think your lack of responses here have been because this cite is mostly aimed at "fighting guns" with maximum reliability and durability, rather than extreme accuracy. Most people don't want to devote much time trying to make their gun as accurate as possible because it can, at times, be detrimental to function.

I've got a timney 3# trigger. Buffer I am un sure of. Whatever comes factory from bushmaster. Hand guard is not free floated. What if I went with an 18" BBL? If head space was ok on my bolt, could I use an 18" barrel with my current gas system or does an 18" barrel require a longer gas tube than a 16"?

I'm not sure of the history of the rifle I own so I just want to slowly change components out until I'm happy with how it functions both in the area of reliability and accuracy and the barrel is the next step in this pursuit for me.

[tylerw02]

I've got a timney 3# trigger. Buffer I am un sure of. Whatever comes factory from bushmaster. Hand guard is not free floated. What if I went with an 18" BBL? If head space was ok on my bolt, could I use an 18" barrel with my current gas system or does an 18" barrel require a longer gas tube than a 16"?

I'm not sure of the history of the rifle I own so I just want to slowly change components out until I'm happy with how it functions both in the area of reliability and accuracy and the barrel is the next step in this pursuit for me.


If you have a carbine gas system, you're not going to want an 18" bbl. unless you replace the gas-block and gas tube. It would be way over-gassed if you didn't extend out to a mid-length system. Usually, you don't want to go longer than a 16" for a carbine.

You didn't say what ammunition you are running that your groups are unacceptable. Maybe you should tweak that first.

[moose01]

Depending on the load you're using, an 18" barrel will typically only give you up to 100 fps over your 16" barrel, and a 20" barrel gives appx 50 fps over the 18" barrel. Again, this is load dependent, but the gains are minimal unless you're shooting at extreme ranges.

If accuracy is what you're after, and you're not trying to push the 5.56 beyond its effective range, then Tyler nailed it with the shorter, stiffer 16" barrel.

As far as the gas system, I'm guessing your Bushy is a carbine length gas system. While you could make that work with the 18" barrel, something longer, like a mid, intermediate, or rifle length system would be optimal with an 18" barrel.

[GermanSynergy]

Instead of buying a new barrel, you may want to consider purchasing a new upper that is better suited to your purpose (shooting coyotes)...

http://www.bravocompanyusa.com/BCM-SS410-16-Mid-Length-Upper-Receiver-Group-p/bcm-urg-mid16%20ss410%20pri12%20ibbk.htm

Put a quality optic on there and some quality ammunition and you're set....

[moose01]

And on the "coyote/prarie dog gun" note, I've had a lot of success with a 16" chrome-lined gov't profile 1:7 5.56 barrel, a free float forearm, a match trigger, a mid length gas system, and a low power optic. Keeps 5 rounds of quality match ammo under 1" at 100 yards, and has no problem keeping minute of yote out to 400 yards. Makes for a lot nicer walking/stalking gun than a heavy barreled 18 or 20 inch rifle, too.

[jdbell2004]

Ok, I think I'll stick with a complete upper then. I've been shooting various hand loads and have come close to 1MOA but feel I could do better with a better barrel and free float handguard. I've got a Nikon Monarch sitting on top of it. I know what I have now would work for coyote, I just want a little more.

I've been looking at Midway USA. They have a DPMS 16" BBL upper and the reviews are good. Price is not to shabby either. I know it's not top of the line, but no matter what I go with, there will always be something better. Any input on these uppers?

[Artos]

I would go with a BCM or Daniel Defense if you are going to get a crossover battle type upper that will still be used for varminting from time to time.


If you are going to get a stainless bbl upper, then flavor is not quite as important for that dedicated application.

[tylerw02]

Considered just free-floating what you have?

[GermanSynergy]

I've been looking at Midway USA. They have a DPMS 16" BBL upper and the reviews are good. Price is not to shabby either. I know it's not top of the line, but no matter what I go with, there will always be something better. Any input on these uppers?


Yes- don't waste your money on DPMS anything. DD and BCM are proven performers, are manufactured and assembled with premium quality components and both will stand behind their products. Why settle for less?

[moose01]

Considered just free-floating what you have?

This. Try freefloating the barrel, and maybe even soften the recoil a bit with a heavier buffer and maybe a muzzle device like the PWS or Battle Comp (just to make your carbine more pleasant to shoot and speed up follow-up shots). I have two identical CMMG barrels (same gov't profile chrome-lined barrel I mentioned earlier), and while the non-ff upper is close to one moa, the ff upper keeps 5 rounds of 69-75gr match loads under 1 moa, and is much more consistent.

If you're close to 1moa, then just a freefloat forend might get you there. You already have a nice trigger, so you ought to have yourself a heck of a shooter with match ammo. It won't be a one-hole benchrest rig, but it'll be more than accurate enough for a fighting rifle or coyote blaster.

[Iraqgunz]

What is your intended use of the weapon? Why do you need just under 1 MOA?

Most people can't even shoot to the accuracy of their weapon.

I know I can only shoot about 1 MOA with my Noveske, using match ammo and a Leupold Mk4 MR/T.


I want to upgrade the barrel on my rig, stick with .223/5.56. I considered a complete new upper receiver but it fits my budget a little better to just go with a new barrel. I want this to be my coyote gun, maybe praire dog too.

I want more accuracy than I am getting with my contour 16" with m203 cutouts. Looking to get just under 1MOA if possible. I'd like to go 20", but if I can get good results with a shorter barrel, I wouldn't mind staying 16" or going 18". Is anything larger than 16" even an option without changing anything else on the upper (ie. buffer assembly)?

I want to use my current upper and BCG if possible. I want a heavy barrel with a gas block. Can I use my old upper and BCG with a new barrel?

So far I believe I will need a take down wrench and a punch set. A new barrel, free float hand guards, gas block and gas tube (length dependent on the barrel length?).

Sorry for all the questions, I searched and couldn't come up with much. The search on this site never works well for me...

Thanks!

Jon