Barrett MRAD barrel change system

[mike10]

I'm trying to understand the MRAD barrel change system. I know the basics of how it works by loosening the two screws and pulling it out, but I want to understand it at a more granular level.

I understand that at the chamber-end of the barrel there is this like black polymer unit and I know there is a notch at the 12 o'clock position that is supposed to be up when you insert the new barrel before tightening the two screws again.

What I don't understand is how the barrel stays in. Is it only tension from the two screws being torqued to 140 inch pounds? It doesn't look like the barrel itself screws in or locks into place in any way other than the tightening of the two screws. For example, watching an AXSR barrel change it's clear to me how it works because you loosen a locking screw and then literally thread the barrel into the rifle and then retighten the locking screw so if the locking screw came loose the barrel would still be in place because it is threaded into the receiver.

Every MRAD barrel installation I've seen the barrel does not screw or lock in any way other than tightening the two screws down onto the barrel so if those two screws came loose would the barrel just fall out the front of the gun?

Thanks in advance for any input you provide.

 

[rustyinbend]

When you slide in the barrel, you find the "notch" and make sure the barrel drops into it and cannot be rotated. Then you seat the bolt ... the right one for the barrel of course, before tightening the barrel screws. This seats the barrel to the bolt, and properly head-spaces the chamber. Tighten the barrel to 140 in/lbs and ... (a) the barrel stays tight with the bolt unseated because of the tight screws, and (b) doesn't walk out when shooting because the bolt is tight against the seated barrel during every shot. Works great ... never a problem ... I LOVE MY MRAD !!!

Does that help?

 

[mike10]

When you slide in the barrel, you find the "notch" and make sure the barrel drops into it and cannot be rotated. Then you seat the bolt ... the right one for the barrel of course, before tightening the barrel screws. This seats the barrel to the bolt, and properly head-spaces the chamber. Tighten the barrel to 140 in/lbs and ... (a) the barrel stays tight with the bolt unseated because of the tight screws, and (b) doesn't walk out when shooting because the bolt is tight against the seated barrel during every shot. Works great ... never a problem ... I LOVE MY MRAD !!!

Does that help?

Yes. Thank you.

 

[rustyinbend]

Yes. Thank you.

You're welcome. I know there are a horde of loyal AI fan-boys around here, but I really like the MRAD form-factor, and have gotten 1-mile hits whenever I tried with barrels in 300-WM, 300-PRC, and 338-LM. Oh ... and my 6.5-CM barrel shoots very accurately out to over 1,200 yards. My MRAD 300-PRC barrel is my favorite. It "dings at distance" any time I want it to. Swapping barrels and bolt-heads at the range always draws a crowd ... takes me about 5-minutes. Never shot an AI ... I'm kind of monogamous when it comes to my MRAD.

 

[mike10]

You're welcome. I know there are a horde of loyal AI fan-boys around here, but I really like the MRAD form-factor, and have gotten 1-mile hits whenever I tried with barrels in 300-WM, 300-PRC, and 338-LM. Oh ... and my 6.5-CM barrel shoots very accurately out to over 1,200 yards. My MRAD 300-PRC barrel is my favorite. It "dings at distance" any time I want it to. Swapping barrels and bolt-heads at the range always draws a crowd ... takes me about 5-minutes. Never shot an AI ... I'm kind of monogamous when it comes to my MRAD.

Hahaha monogamous with your MRAD. Why is the 300 PRC barrel your favorite?

 

[rustyinbend]

Hahaha monogamous with your MRAD. Why is the 300 PRC barrel your favorite?

I've got a super-tuned load for it that shoots as accurately as any rifle I've ever fired. Whether tight groups at 100, or dinging steel at a mile ... it just seems to always do the job (as long as I do mine).

 

[mike10]

What's the load? Got any pictures of groups?

 

[rustyinbend]

What's the load? Got any pictures of groups?

No photos ... half-MOA-ish at 100 yards. Here's my favorite load:

 

[mike10]

Love that. I've had some luck with 220 grain LRHTs in my Bergara hunting rifle -- they just seem to shoot. Thanks for all the input, man.