AR Barrels, what are we trying to do

[kurtm]

Today I took my iron sight carbine out to the range to do some long range practice and reafirm my zero. The barrel is a chrome lined 1X9 Bushmaster fluted 20". This particular carbine has over 8000 round through it and is a very high volume rifle. I haven't been very nice to the barrel. An occasional full Beta, full 30round mags at one time, not enough time to cool, I have had it smoking on more than 5 occasions. Once I could see a color change in the barrel chrome, kind of like a bike pipe. Now this barrel was cheap, like $225.00 all set to go. I did a couple of bounces @ 300yds just to get it warm (12 rounds per bounce, total time about 2 min.), and settled into a nice prone with the old Ching sling and put a nice 2 3/4" group in the middle of a bullseye target at 300yds. Well ok not quite the middle as there was a fairly constant wind from the 10:00 and the group was about 3" from exact center, but still all 10 ring shots. This isn't atypical performance from this type of barrel. The load was a NICE 55 gr Nosler balistic tip over AA2460. Next I mono poded and sent 10 rounds as fast as I could make sure of good hits at a MGM swinger and had it rocking with NO misses @ 300.

Now I know what you are thinking...what does this have to do with anything. Well I keep reading and running into people that feel they need "match" barrels to obtain any useful accuracy out of an AR. Some of these people have paid "cubic" dollars to get a cool SS 1X8 that will drive tacks just to burn 40 rounds through it as fast as they can pull the trrigger. The barrel life is about done at 5000-7000 rounds and then they "need" a new one. For 3-gun, a barrel that gives 1 MOA and will take abuse is much more practical than a 1/2 MOA barrel that quits after the first 5000 or so. I know a 1X9 won't supposedly work for those "heavy" carbine bullets but at 300 what do you really need?? You can bet that I will soon have a few more Bushmaster barrels that are fluted and chrome lined. I know of 4 other barrels just like this one and all are 1MOA or better; but then you can't brag about owning a XXX barrel with a XXX twist that will hold about 1 inch better than a Bushy chrome lined. I just feel it's about time we ask What are we trying to do with this here carbine. KURTM

[Loves2Shoot]

Cool factor

[Bear1142]

Kurt,

Nice write-up. I'm working on some barrel issues myself. It involves some old technology with some new revolutionary design processes. If all of the performance claims are valid, this barrel will change everything. Stay tuned.

Erik

[michael_aos]

Good timing.

I've got a pretty much factory-stock Armalite M15A4. Specs are 1.5-2MOA, and that's what I see.

I was just going to get the barrel free-floated and hope for the best, but since I don't really know how many rounds I've put through it (3K?, 5K?) I went ahead and ordered a JP SS 1:8 barrel at the same time.

I agree .5MOA is overkill, but 2MOA doesn't install a lot of confidence.

Mike

[pisgahrifle]

I've got a pretty much factory-stock Armalite M15A4. Specs are 1.5-2MOA, and that's what I see.

I was just going to get the barrel free-floated and hope for the best, but since I don't really know how many rounds I've put through it (3K?, 5K?) I went ahead and ordered a JP SS 1:8 barrel at the same time.

Shoot your factory barrel (floated) first so you can send the JP back if you don't need it! My Eagle Arms A2 did 1/2 all day long once I floated it. I haven't stretched it any farther than that, noe do I probably intend to. Nonetheless, it's still "good enough for gummint work!"

[EricW]

Liar! Heretic! Infidel! Incompetent!

==============================

OK, now that we have the obligatory name-calling out of the way. I'm *really* glad you posted this topic. It really reinforces my desire to go to a chrome-lined barrel once I shoot my current one out.

I'll take consistency, reasonable accuracy, and durability over high-zoot any day.

[pisgahrifle]

Yeah, I almost forgot- both my A2 barrel and my lead-hose bbl. are chrome moly. Lots of the high-power folk still shoot them for the simple reason that unless you're already a high master you'll get more mileage with CM.

Which brings up another point- you sometimes need those super-duper 1/8 and 1/7 barrels in high power, but I agree with you in that I don't much see the need in three gun. (You don't see the "cool factor" here though- it's either shiny or it ain't, and everyone's gotta get it under handguards and through a front sight block) Sure, it's nice to have, but awful pricey when you can get the job done in 1/9.

You can also get a passable CM barrel for less than $200. A friend of mine's got a 1.5 MOA lead hose DPMS M4 profile he picked up for $140, gas block and barrel nut installed. A little short, but it works.

[MikeFoley]

I have had good chrome lined factory barrels from Bushmaster and DPMS, but I put the JP on my first build gun because I liked the weight reduction under the handguard, I liked the Bennie Cooley compensator, I liked getting the kit with the gas block, comp, and barrel together, I liked their claims to accuracy(even if I don't need it), and I like the way JP supports the shooting sports(he is one hell of a nice guy).

Now, on the notion of not needing 1/2 MOA...You don't need 300 plus horsepower engines to drive to work in rush hour traffic, but I see plenty of them on the streets. I heard someone say once regarding custom pistols..."get the most accurate gun you can so that the rest is truly up to you"...I guess I am trying to say that we buy a lot of things we don't need, but if you do need them, you'll be glad you bought them, if you never use them to their capacity, what did it hurt. I'm guessing a lot of guys on this forum have highly accurate pistol barrels that only shoot USPSA targets in local matches at less than 20 yards where accuracy probably won't even get you an occasional broken line for the next highest scoring zone.

Factory is fine, you don't need benchrest rifle accuracy, but I shot a lot better when I built this last gun imediately. Maybe it is psychological, but the scores are higher.

[chp5]

Bushmaster makes good barrels.

It's refreshing to see a 3G Big Dog shooting a non-high end barrel.

Good thread Kurt.

[Sam]

Thanks, Kurt! This is a very informative thread for me. You've got me to thinkin'.

[SinistralRifleman]

I think 2MOA accuracy is reasonable for most 3 gun action shooting. The targets we shoot at are generally larger than even a 4MOA group out to 300 yards.

With my 1.5-2MOA rifle I've successfully engaged man sized (18" across) steel targets at 600+ yards without much trouble.

I agree with Kurt that longevity and reliability trumps marginally increased performance.

[Bronco]

If your budget allows custom barrels get what you want. If on the other hand your shooting fund is limited than your a lot better off spending the money you have on ammo or components and practicing. I shoot a light contour 20" 1 in 7 chrome lined " gun show special " that I paid $150.00 for. If I do my part it will hold sub minute groups out to 700 yds. The best shooters out there are not beating us with equipment they practice more and have the skills. You could give me the best rifle for the task at hand and Kurt would still kick my a$$ with my own gun because he has put in the time and effort to know what he's doing. I'll take a rifle that is dependable and shoots 2 min. over one that is a one holer but temperamental.

[Mig]

Kurt,

Excellent write-up and well stated.

Bear1142,

What's your secret project this time

[MattBurkett]

Kurt, I agree that a 1 moa or better gun is all that is needed for the sport for most of the competitions. Nearly all guns coming out of the factories (except C*lt) these days meet that standard when they have a free floated handguard. That seems to be very critical. Another issue that people need to check is to see if the barrel "walks" when hot. If it does get another one.

Some other things to think about:

I think where most people miss the boat cost-wise is on ammo. You don't need to shoot 69 or 77 grainers at 200 yards and less. Shoot cheap 55's instead. Just make sure they hold some what of a group out to your swapover distance. I want to be able to make head shots on an IPSC target at 200 without an issue with the 55's. With 77's it should be less that 3" at 300.

:-)

[kurtm]

Fomeister:

The barrel is flute so it is as light as the JP, It has a realy nice brake specially made by Benny Hill for an extended sight radius, It has a really nice gas block. It has a nice Briley free float tube. Just because the barrel is a "stock" barrel doesn't mean it has an A2 flash suppressor, the little thready things at the end of the barrel allow all sorts of comps to be screwed on including the Bennie Cooley brake if so desired. Yes My JP rifle is very accurate it will hold 1/2moa or less, Yes my Bushmaster will hold 3/4 moa. So lets see, instead of 1.5" groups at 300yds for the JP, it throws a "huge" 2 3/4" group, after 8000 rounds. Once you get 8000 through your JP barrel let us know what it groups. I am a firm believer in Horsepower, but I don't get too wound around the axel if my street glide has 300 hp or 290hp its pretty much close enough. I don't know many shooters that can hold that extra 1.25" from field positions at 200yds, let alone at 300. KURTM

[EricW]

Kurt,

3/4 x 3 = 9/4 = 2 1/4".

It's even better than you think!

[kurtm]

If I drop the one and carry the two it still comes out better than it ever needed to be and besides unless I have all the time in the world to shoot a good group from prone or happen to find a stage that the first position is off a sandbagged bench 1 or 2 inches just doesn't matter.

Now if I got that split manifold for my diesel I could gain 10 hp and 30 ftlbs of torque, except when I last dynoed it, it was putting out 300 hp and 880 ftlbs of torque. Do you think I will notice a BIG increase?? Or will it still just roast the rear tires at will anyway. KURTM

[EricW]

All I know is I'm going with the split gas tube for my AR, so I can smoke my buffer at will. More is always better, no matter what the cost.

[kurtm]

As the add says "more is more", but you didn't post the important stuff like % gain with the split gas tube, and if it ain't pakaged in yellow it ain't really a "gofast" part. KURTM

[SinistralRifleman]

To me, "go fast" = full auto

w00t!

[kellyn]

Kurt, I agree but I like to shoot itty bitty groups. It makes me feel good.

One other theoretical advantage of the fancy schmancy custom barrel is consistency of zero. I don't have any hard data to back it up but my hunch/feeling/opinion is that properly chambered, massaged and mounted custom barrels hold zero ON AVERAGE better than stock barrels. Is it true, I don't know but I feel that way.

Matt is right about ammo. Launching a 77 Sierra at a 25 yard IPSC target is almost crime (unless it's a big match and that's your match load).

[DblTap]

These were fired at 300 yards thru a Bushy 1x9 Chromed Gov't profile. The load is nothing special, Win 55 PSP over AA2200 in LC unsorted/unprepped brass. I have no problem with chromed mil spec barrels for 3 gun. In fact, I prefer them.

[Wap wap]

Use one top with an accurate 416 stainless for varmits and groups, shoot it out cut it down for action shooting. Good stainless will shoot more than 8000 rds, and still be under an inch.Unless you are using a 1/8 " crosshair sub 1 inch groups are difficult and uneccesary in practical and action shooting. Besides the additional time factor would kill your score. Bushmaster and Robinsons barrels have Nato chambers which have longer leade which allows for lower chamber pressure on rapid fire. SAMMI chambers have shorter and when severly heated cause higher chamber pressures. From a practical standpoint, to me a least the .223 power factor sucks. 65 gr. Win. PP reloads allow for shorter barrels with a better power factor. 26 inch .223 with 69 gr will reach 3300-3400 which gives it about the same parabola as 168 gr. .308. (bolt guns).

[Religious Shooter]

In a class, Cooley recommended that you have a practice upper and a match upper --- which I do. You set them up as identically as possible and as they are named, you use the practice upper to practice (and shoot the shjt out off) and the match upper you only use for matches.

This year I am shooting three majors @ 150 rounds (Area 2, RM3G and Nationals) and 12 or so club-level matches at 100 rounds a piece. I'm looking at 3x150 + 12x100 = 1650 rounds per year that will be shot at matches with my match upper. I figure that's about average for the average shooter.

So even if the match barrel goes to pot at 8,000 rounds (which is very unlikely) to me that's at least 5 YEARS worth of shooting. And heck, after that 5 years you continue to use that upper as the newer practice upper.

... half a decade. That's not so bad is it?

That said, both of my $175 DPMS barrels are sub MOA with hand loaded rounds.

But if I could afford it get me one of 'dem match barrels.

[gl]

Kurt,

I agree with you that a Bushmaster barrel is usually great as far as consistancy of group position and size and usually accurate (matter of fact almost every time is accurate!). But I must agree with Kelly that if the barrel is cryo'd (like JP's) it probalbly is more likely to stay consistant when it gets hot and zero will not be as likely to 'float around'. I have shot Bushmasters for years and don't seem to have a problem competeting with them, please no smartass comments Kelly! But when I pick up a JP with a Coolie comp on it even I must admit there is a difference in control of the weapon because of the comp and the lengthened gas tube (I shoot a dissipator with a short gas system). I don't have a problem with the Bushmaster because, like you, I have put tens of thousands of rounds through the same model and I am used to the recoil.

If you are on a budget, or if you just want a good value for your money, Bushmasters are the greatest without equal (shameless, and honest, plug for Bushmaster!!). But I will not begrudge someone for wanting a JP either for the slight advantage it may give them. The fact remains if you put in the time training it will pay off more on average than putting your dollars toward and finer piece of equiptment, but better equiptment never hurt either.

On another note, I wish you and everyone else good luck ar SSM3G!! I burned myself and I can't go. Do well and may the best person win!

Guy Hawkins

P.S. Kelly you have permission to slay all those who oppose you.

Lawyers Rule!