The short and the long of the short barrel.

Dear Master Sergeant T.A.,

When you switch to a short barrel, you must re-zero your M249 by adjusting the front sight only. That allows you to use the standard and short barrel from then on without re-zeroing.

The Army doesn't want you to fire blanks through the short barrel. It's possible blanks fired through the short barrel increase the unlocking velocity of the bolt when it leaves the barrel socket. That increased velocity could damage the receiver's inner rail, which makes the M249 unusable. Use the standard barrel for firing blanks, along with the M249 BFA, NSN 1005-21-912-8997.

If you've already fired blanks through the short barrel check the inner rail jor cracks. See Page 2-45 in TM 9-1005-201-23&P for directions.

Dear Half-Mast,

We've started using the new short barrel, NSN 1005-01-475-4296, on our M249 machine guns and we were wondering if you need to re-zero the gun when you switch to the short barrel? Also, is it OK to shoot blanks through the short barrel?

MSG T.A.

For more info, see TACOM Safety of Use Message 04-005. Contact your TACOM logistics assistance representative for a copy or TACOM's Mark Johnson at DSN 793-1918/[phone] or email:

[e-mail]

HEY, I'M GOING OUT TO THE RANGE TO SHOOT BLANKS.

YOU COMING?

I BETTER NOT. I'M NOT SUPPOSED TO FIRE BLANKS.

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