Hey guys, got my first AR a few weeks ago and it's my favorite rifle in the collection now hands down.  I got a Bushmaster 20" A3 from AIM.  I have really been enjoying it, but was wondering how much I should worry about ripping thru the USGI 30 rounders?  I realize the barrel is HBAR and the mil boys run thru the ammo very quickly, but I don't have the pentagon budget and don't want to wreck the barrel. Any thoughts?  Been reading the forums for a few months now and really enjoy this one!

THANKS!

Welcome to the insanity! [beer]

I wouldn't worry about it to much. I have heard some conservative numbers on the amount of rounds fired in one minute and exceeded them many times. I have discolored my barrel on my Bushy several times and still no ill affects that I have noticed.

If you are shooting a semi rifle and on a tight budget you probably aren't shooting to much ammo anyway.[;)]

Ummmmmmm, don't worry 'bout it!

I rip thru several 30 rounders at a time with an Bushmaster upper on an M16.  Yeah, it gets REAL HOT! I used to worry but what the heck, just get another barrel after 5-10K rounds.  That's about $150 - or less every year or so.  2 - 3 years in semi.

It's worth it. Even on a budget

PS:  I just reread the above, I know you said you had budgetary concerns.  I don't want to sound like a *ick, I really don't.  But it is still worth it!  ;)

Firing an AR semi auto you can not get it hot enough to hurt it.

Thanks guys!  I just never had a rifle with this much capacity and did not want to wreck my newest toy.  The I think I'm doing pretty good, 3 times to the range in the last couple weeks and almost ran thru 500Rds.  The thing shoots like a dream and can't believe I waited so long to get one.  I have been messing around with foreign military rifles that last few years and thought they where great, but now I know......  I'll be getting a M4 type soon.  

[/size=6]Wear gloves!  
[/size=2]When doing all that shootin [:)]

This is some interesting info I found searching the subject on google...


VERY IMPORTANT FIRING NOTICE


Anyone firing M16, AR15 types or M4 series rifles must follow the procedures below to ensure that there are no cook-offs.

Subject: GROUND PRECAUTIONARY MESSAGE (GPM), 97-03     5.56MM M4A1 CARBINE
Importance: High

GROUND PRECAUTIONARY MESSAGE
ACALA #97-03
DATE: R 051413Z NOV 96
CLASSIFICATION: UNCLASSIFIED (1nn)
SUBJECT: GROUND PRECAUTIONARY MESSAGE (GPM), 97-03 5.56MM M4A1 CARBINE

1. DISTRIBSubject: GROUND PRECAUTIONARY MESSAGE (GPM), 97-03     5.56MM M4A1 CARBINE
Importance: High

GROUND PRECAUTIONARY MESSAGE
ACALA #97-03
DATE: R 051413Z NOV 96
CLASSIFICATION: UNCLASSIFIED (1nn)
SUBJECT: GROUND PRECAUTIONARY MESSAGE (GPM), 97-03 5.56MM M4A1 CARBINE

1. DISTRIBUTION: {MENU}  THIS IS A GROUND PRECAUTIONARY MESSAGE THAT HAS NOT BEEN TRANSMITTED  TO SUBORDINATE UNITS. SOCOM COMMANDERS WILL IMMEDIATELY RETRANSMIT THIS MESSAGE TO ALL SUBORDINATE UNITS, ACTIVITIES OR ELEMENTS AFFECTED OR CONCERNED. RETRANSMITTAL SHALL REFERENCE THIS MESSAGE. SOCOM COMMANDERS WILL VERIFY RECEIPT WHEN RETRANSMITTING THIS MESSAGE BY SENDING AN INFO COPY OF THE RETRANSMITTAL TO DIRECTOR, TACOM-ACALA, AMSTA-AC-ASIR, ROCK ISLAND, IL.

2. PROBLEM DISCUSSION:

A. SUMMARY OF PROBLEM: SEVERAL INCIDENTS OF COOKOFFS, IN AND OUT OF BATTERY, AS WELL AS BURST BARRELS, HAVE OCCURED WITH THE 5.56MM M4A1 CARBINE. THESE INCIDENTS HAVE RESULTED IN INJURIES TO WEAPON USERS. THESE INCIDENTS RESULT FROM FIRING NUMEROUS ROUNDS WITHIN A SHORT AMOUNT OF TIME WITHOUT ADEQUATE COOLING.

(1) COOKOOFFS OCCUR WHEN A LIVE ROUND IS LEFT IN THE CHAMBER OR IN CONTACT WITH THE CHAMBER OF A HOT WEAPON AND HEATS TO THE POINT THAT THE PROPELLANT IS IGNITED.

(A) SUSTAINED FIRING OF THE M16 SERIES RIFLES OR M4 SERIES CARBINES WILL RAPIDLY RAISE THE TEMPERATURE OF THE BARREL TO A CRITICAL POINT.

(B) FIRING 140 ROUNDS, RAPIDLY AND CONTINUOUSLY, WILL RAISE THE TEMPERATURE OF THE BARREL TO THE COOKOFF POINT. AT THIS TEMPERATURE, ANY LIVE ROUND REMAINING IN THE CHAMBER FOR ANY REASON MAY COOKOFF (DETONATE) IN AS SHORT A PERIOD AS 10 SECONDS.

(C) WHEN THE WEAPON HAS REACHED THE COOKOFF POINT (OR TEMPERATURE) A ROUND SHOULD NOT BE LEFT IN THE CHAMBER FOR ANY LENGTHY PERIOD OF TIME. THE WEAPON SHOULD BE CLEARED AND THE BOLT LOCKED TO THE REAR TO ALLOW COOL DOWN.

(D) SUSTAINED RATE OF FIRE FOR THE M16 SERIES RIFLES AND M4 SERIES CARBINES IS 12-15 ROUNDS PER MINUTE. THIS IS THE ACTUAL RATE OF FIRE THAT A WEAPON CAN CONTINUE TO BE FIRED FOR AN INDEFINATE LENGTH OF TIME WITHOUT SERIOUS OVERHEATING.

(E) THE SUSTAINED RATE OF FIRE SHOULD NEVER BE EXCEEDED EXCEPT UNDER CIRCUMSTANCES OF EXTREME URGENCY. (NOTE: A HOT WEAPON TAKES APPROXIMATELY 30 MINUTES TO COOL TO AMBIENT TEMPERATURE CONDITIONS).

(F) THE USER'S MANUAL (TM 9-1005-319-10) FOR THE M16 SERIES RIFLE AND M4/M4A1 CARBINE STATES, "THAT IF A MISFIRE OCCURS IN A HOT WEAPON, REMOVE THE ROUND FAST (WITHIN TEN SECONDS). IF THE ROUND CANNOT BE REMOVED WITHIN TEN SECONDS, REMOVE THE MAGAZINE FROM THE WEAPON, POINT THE WEAPON IN A SAFE DIRECTION AND WAIT FOR 15 MINUTES."

(G) CAUTION SHOULD BE TAKEN BY THE USERS TO KEEP THEIR FACE AWAY FROM THE EJECTION PORT WHILE CLEARING A HOT WEAPON.

(2) COOKOFFS OUT OF BATTERY RESULT FROM A ROUND WHICH COOKS OFF WHEN THE BOLT IS NOT LOCKED OR A ROUND WHICH COOKS OFF AS THE USER IS TRYING TO CLEAR THE WEAPON.

(3) BURST BARRELS RESULT WHEN THE WEAPONS ARE FIRED UNDER VERY EXTREME FIRING SCHEDULES AND THE BARREL TEMPERATURE EXCEEDS 1360 DEGREES FAHRENHEIT. WHEN THE BARREL REACHES THESE EXTREME TEMPERATURES, THE BARREL STEEL WEAKENS TO THE POINT THAT THE HIGH PRESSURE GASES BURST THROUGH THE SIDE OF THE BARREL APPROXIMATELY 4 INCHES IN FRONT OF THE CHAMBER. THIS CONDITION CAN RESULT IN SERIOUS INJURY.

6. POINTS OF CONTACT: {MENU}
THE POC FOR MAINTENANCE ON THE M4 CARBINE IS MR. NEAL CHRISTIANSON, AMSTA-AC-ASIR, DSN 793-0034, COMMERCIAL (309) 782-0034, FAX DSN 793-7005, E-MAIL [email protected].
THE POC FOR ARDEC, THE DESIGN AGENCY, IS MR. JEFF WINDHAM, AMSTA-AR-ESWS, DSN 793-8162, FAX DSN 793-6339, E-MAIL: [email protected].



John S. Olson
CW5 John S. Olson
Munitions Materiel Management Officer
NGB-ARL-E
DSN 327-9413
COMM 703-607-9413
FAX nnn-8529