77 gr Sierra in AR 15 mag

[Ailean Mac an Daroch]

I have been shooting 69 grain Sierra match bullets and doing fine, but want to try the 77 grain in my 1:8" twist barrel. However, before I go buy a bunch and find I cannot use them.... what's the experience on the board regarding loading 77 grain bullets deep enough to work out of an AR 15 magazine?
Thanks

 

[Scorch]

I have no experience with that particular bullet, but I do shoot Service Rifle Match with an AR. I believe you will find the bullet is too long to load loaded rounds into your magazine.

 

[STLRN]

The 77 grn OTM is the round used in the Mk262 round issued to SDMs, SAMs and elements of SOCOM. It shouldn't be a problem.

 

[Zak Smith]

As STLRN said, it works fine. Black Hills and Federal both have mag-length factory loads with this bullet.

 

[HorseSoldier]

Yeah, works just fine.