I was told by a friend this evening that Colt barrels sometimes won't work with upper receivers unless its Colt.Although I am far from an expert but this soounds like complete B.S. to me.


Would any of you guys mind 'splainin for my friends benefit? If anyone has had a bad experience with a Colt barrel I would like to know. I was planning on selling a barrel to him when he brought this up.

THX

I don't think that is true- I have a Colt Pre-Ban which I put a Bushmaster M4 barrel on it, then sold my Colt 1/7 20" to a guy who put it on something else (Sendra maybe) and has had no problems that I know of. My Colt has never had any problems since the Bushmaster barrel was installed- eats Russian Laquer cased .223 like candy. Now some 2,000 rounds of the Russian greenies later it still has yet to jam- once again another myth, Russian ammo screws up your gun, yah right.  

You sir, are correct, that IS B.S., unless the receiver is a really wacky non-milspec upper.  I don't know of any that bad...

Depends,
You can get failures to feed using barrels with standard feed ramps in uppers with M4 ramps, with Colt those uppers will have a "4" stamped at 12 o-clock above the gas tube cloverleaf. The tip of the rounds will/can get snagged under the lip of the barrel extension, esp on carbine length barrels. Colt barrels with M4 ramps will have a "4" stamped at 3 o-clock on the rear of the barrel extension.

Or,
If you use a Colt barrel with an "F" marked front sight base on a fixed handle upper there won't be enough elevation on the front sight post for a proper zero.

"My Colt has never had any problems since the Bushmaster barrel was installed- eats Russian Laquer cased .223 like candy. Now some 2,000 rounds of the Russian greenies later it still has yet to jam- once again another myth, Russian ammo screws up your gun, yah right. "


Not so this is true laquer cased ammo can screw up your gun if (you fire till your barrel is pretty hot and then let a round sit in the chamber for a little longer than it takes to pull the charging handle you could find it stuck in the chamber.  )

If youy shoot semi-auto and not abusively or (quickly) you might never have a problem.

The only "problem" with Colt barrels, AFAIK, is that the M4 barrel has a slightly taller front sight tower than other manufacturer's. As the Colt M4 is the "Mil-spec", companies that make accessories for the M4 (KAC, ARMS,ect.) make their products for for the Colt sights. This can/does create zeroing issues with the accessories and other manufacturer's barrels.

small hole vs large hole has nothing to do with the barrels, but yeah, there is a problem if you use an M4 ramped upper with a non-M4 ramped barrel...

Its BS.  Ive had a Colt barrel installed on an Eagle upper with NO probems.

Quoted:
"Not so this is true laquer cased ammo can screw up your gun if (you fire till your barrel is pretty hot and then let a round sit in the chamber for a little longer than it takes to pull the charging handle you could find it stuck in the chamber.  )

If youy shoot semi-auto and not abusively or (quickly) you might never have a problem."


Actually this is not so- I run the shit out of my Colt AR M4- mostly bump firing. Sometimes I run six mags back to back bumping most of the way- then after about the fifth mag I have left rounds in the chamber and it still doesn't jam on the fifth or sixth mag, remember to the barrel will turn white when it gets hot enough. Never a single malf with this rifle.
I use exclusively Wolf because of two reasons: first it is cheap especially when you just bump fire for fun, second because of the hysteria and myth with using laquer ammo to prove it works fine. I hated AR's for a long time partly because of experience in the service and partly because  I collect AK's- I wanted to prove the AR is not as reliable as the AK and I proved myself wrong. This thing eats the Russian ammo all day and I have yet to have it jam. I abuse my rifle because  simply a new barrel is only $250 versus my AK's which cost a small fortune to re-barrel. However I have several friends with AR's that may not be mil-spec but either way they can't run the Russian green all day- one guy has an Eagle with a Sendra barrel, the other has a Colt lower with a DPMS upper, and the third guy has a Sendra Lower with Oly upper. All have problems running Russian laquered case except my Colt lower/Bushmaster Upper Combo. I am now convinced the AR is just a tough as the AK when it comes to eating that paticular ammo- I didn't clean it for the first 1500 rounds just to prove it would jam and it ate another 500 without a problem. Personally I love this little AR now.
Creeper  

One more thing: here's the kicker, not only do I run exclusively the cheap Wolf ammo but I also only use $9 Orlite mags which are beast near to death- now figure that out...

I don't think this M4 would jam unless I shoved sand in the chamber. Every time I go to the range my friends use their GI mags with green followers with their Lake City or other brass cased surplus and sure enough they will have jams throughout the day even with the best combo's. If your AR jams it is because it is out of spec and has nothing to do with ammo or mags unless they are aftermarket.  

Hey guys,

Thanks for all the info regarding Colt barrels! I kinda figured that this was B.S. all the time!

I do know that it had nothing to do with large pin V.S. small pin. If I recall correctly it had to do with barrel indexing and canted sights.

If I'm not mistaken ,this "problem" can happen with all brands of AR upper receivers if you overtighten the barrel nut. Its not specific to Colt products. If I'm wrong here LMK.

I appreciate you guys taking the time to answer my question!

Marty

The problem that occurs with the elevation adjustment on the front sight from different brands,can't that be taken care of by using a taller sight post?

I have seen .040 taller posts for sale on a couple of websites.

Incidentally,where would the "F" be located on the sight mount. Both of the current barrels I have are 20" preban. One is a government profile and the other is a green label Hbar.

The gov. profile is the one I'll probably sell and it will be replaced by a 16" Hbar cut to 14 1/2" and installed on a Colt A3 receiver

Somewhat, quite often the tip of the post extends past the protective wings of the FSB, effectively negating the design.



Pics and descriptions [url=http://ar15.com/forums/announcement.html?b=3&f=66&id=188]here[/url] at the Troubleshooting Forum Glossary. There's probably more info in one of the FAQs there too.

Here's the pic.
[img]http://photos.ar15.com/WS_Content/ImageGallery/Attachments/DownloadAttach.asp?sAccountUnq=12467&iGalleryUnq=934&iImageUnq=16149[/img]
Notice the stamped "F" on the left side of the gas tube bracket of the FSB, forward of the gas tube roll pin hole.

Barrel torque has nothing to do with sight misalignment, aka "canted barrels". The alignment is determined by the location and width of the alignment pin slot in the upper receiver and the correspondance between the alignment pin (and its width) in the barrel extension and the front sight post. If either, or all, of these are off the barrel will sit in the upper rotated slightly. If there is slop between the pin and the slot the barrel will/can rotate when the nut is tightened during assembly.



If you intend to install it on a Colt flattop you'll need a barrel with the correct height FSB.

Creeper,

Like you, I have never had problems with Soviet steel cased and laquered (either case laquer or annulus waterproofing) ammunition in my ARs. All my ARs wear Colt barrels. Most function problems with ARs can be fixed by installing a correct barrel.

I think Tweak is right.  I'm sitting here, and in one hand I've got a Colt M4 upper and in the other hand is Bushmaster A3 upper.  Sure as shit!  I'd bet I would have feeding problems if I used the Colt M4 upper with the Bushy A3 barrel.  The tips of those bullets would nose-dive right into the front of the upper reciever.  

You [b]think[/b] I'm right huh? Thanks for the vote of confidence.


[;D]

Please let us know who sells Colt barrels for only $250?

I'm glad I came across this.  Got the Colt M4 upper.  Was planning to replace the 16" barrel with a Bushmaster 14.5 barrel.  I've e-mailed them on this question of feed ramps on their M4 barrels being compatable with the Colt M4 uppers.

Any bets on what the response will be?

Any issues if using a "not F" front sight base on a flat top upper?

Thanks
John

He's running a Bushmaster barrel.

[b]My only problem with Colt is the price.[/b]

As far as the laquer I was just repeating what someone described on how they got a Wolf case stuck in their chamber after a lot of full auto fire- I've seen red hot barrels but never white hot.

"I don't think this M4 would jam unless I shoved sand in the chamber. Every time I go to the range my friends use their GI mags with green followers with their Lake City or other brass cased surplus and sure enough they will have jams throughout the day even with the best combo's. If your AR jams it is because it is out of spec and has nothing to do with ammo or mags unless they are aftermarket. "

There's some truth to that, in a Crane test of 5 CQBR's reliability results varied wildly, I think the worst rifle had over 30 stoppages in 1000rds and the best had less than 7.  I bet all 5 were in spec (or why test them at all), but that doesn't mean that I don't believe one  experienced stoppages 4 times as often as the others.

[b]The test involved firing 300 rds at a crack, in 3-9 rd bursts, 10% of the firing was done with M4 QD sound suppressors, and allowed for cooling after every 300rd string.  That is a lot of abuse and explains the stoppages, and parts breakages (most common being the gas tube)[/b]

Obviously there are luckier guns. (maybe that somewhat explains why there always seems to be one rifle that just won't function with blanks).

The elevation of the front sight post will be off 0.04" the other direction if you mount a BUIS.

AKM,
Colt barrels for $250 [url=http://www.sawlesales.com/jsps/sku.jsp?field=Part&value=SA02013]here[/url].

Green0,
The military spec is pretty lenient, I think that's partly why the rifle's performances are so variable.

newbe,
My bet is that BFI is using the lowered feed ramps. I don't know if that feature is patented by Colt but it is turning up on more and more maker's barrels.

Thanks for the info on Colt "F" front sight towers.

Like the $250 HBAR barrel, however, hate to see the bayo lug missing (not that I need one [;)], which is probably the reason for the sale.

Any leads on a flattop A2 profile chrome lined Colt upper or a "F" barrel (just got an ACOG and now it "needs" it's own upper ... as soon as I get it back off a friends AUG).

Regards
John

That same link should lead to all the Colt parts you could ever want, or afford. [:D]

The afford is the limit, sorry to say [;(], however, did not see a single A2 chrome lined barrel / upper in the bunch (for a M16A1 so like to stick with chrome and a 5.56 chamber), however, may be reading the listing incorrectly (i.e Gov barrel may indicate is chrome lined).

Did like your lead on the $250 HBAR, in particular since looks to be $150 or less than the rest (over a hundred which is a lot for a lug ;-).

I mated a RRA flat top upper to a Colt 1/7 barrel with no ill effects.  Five range trips and about 400 rounds of slow fire without any malfunctions using ammo from 77 to 55 gr.


Jim

omar,

Were you using a BUIS or scope?

http://www.gunsamerica.com/guns/976389761.htm

http://www.gunsamerica.com/guns/976389489.htm