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Re: MAB barrel blowup!

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04 November 2004, 16:39
HIPPYHUNTER
Re: MAB barrel blowup!
Sorry to say it goes a lot deeper as in one of my earlier posts 6.5 284 wildcat I will no longer shoot it apart from excesses head space heres the story.



Letter as follows from QRA

9th September 2004





U R G E N T M E M O R A N D U M





MAB BARREL FAILURE



Further to our statement of 7th September 2004 with respect to the MAB Barrel Failure and the intercepted barrel that was being recalled by MAB, NRAA contacted MAB through their Solicitors requesting a satisfactory response from them by 9.00am 9th September 2004 on those findings. No response has been received.



The findings as preliminarily relayed to us were as follows:



1. Two barrels were tested, the burst barrel and another barrel that was the subject of MAB�s recall but was intercepted by our client, identified as #605.



2. The main contributing factor to the failure of the burst barrel was identified as striae in the bore ostensibly caused by a cutting tool (used to cut the rifling) whose cutting edge was unfit for purpose.



3. The recalled barrel #605 also displayed signs of striae as referred to in numbered paragraph above.



4. The percent composition analysis indicates that the two barrels are not related to each other in terms of their bar stock.



5. Neither of the barrels conformed with the certificate from the Gloria steel mill in Taiwan that was supplied to Dr Krstic by MAB.



6. The Rockwell C hardness of the steel in the intercepted barrel #605 was alarmingly low, and in Dr Krstic�s opinion, the barrel was a �disaster in waiting�.



From this we conclude the following:



1. MAB�s operating procedures in regard to maintenance of its tools appear inadequate to ensure the safety of its cut-rifled barrels.



2. We have no means of ascertaining when rifling began to be cut with improperly maintained tools and therefore no means of ascertaining which MAB cut-rifled barrels are affected or not affected by those features.



3. It would seem that MAB has no reliable audit trail for identifying the batch of steel from which a barrel is made.



4. We have no means, therefore, of ascertaining which MAB stainless steel barrels, cut-rifled or button-rifled, are made from the same batch of steel as recalled barrel #605.





In the circumstances, therefore, we are unable to determine which MAB stainless steel barrels are safe and which are not. If the striae in the bore were the only problem, it would only be concerned about cut-rifled barrels. The issue with the excessively soft steel, however, applies equally to button-rifled barrels.





However, as our normal club and State activities continue and our national team championship is scheduled for the coming weekend, NRAA has taken the action to no longer permit the use of MAB stainless steel barrels on any rifle ranges. NRAA would have preferred to co-operate with a total recall by MAB rather than issue a ban unilaterally.



This action is taken reluctantly, but with the interests of shooters� safety in mind.





We thank you for your co-operation









Christine McShane

Executive Officer

09Sept04



As they say sh*** will hit the fan
09 November 2004, 19:17
Stu C
Mine's a CM 9.3 barrel. So far only about 40 rounds put through it.
10 November 2004, 00:22
Bad Ass Wallace
My 375 MAB barrel (Oct 2001), is up to 1200 rounds of full loads no problems at all!
09 November 2004, 18:21
416SW
Unsure about whether they are cut or button.
I would like to know after how many rounds fired they failed, I've put about 200 rounds through mine.
How n\many rounds through yours and what cal