Bedding AR10 barrel

[GenePoole]

Yes, and it is a pain in the ass. To get enough heat to where you need it, you end up damaging the delta ring or its spring

 

[LVLAaron]

Yes, it takes 300 degrees and it's a pain in the ass.

Worth it.

 

[Twdmar]

you dont necessarily need heat. If you do heat it, it doesn't really take a lof heat. you can use a propane torch and the amount of heat will not necessarily ruin the delta ring or spring (who uses those but highpower guys). Just don't let the torch sit too long. I would assume you could also take it apart with an iron like some bench rest guys remove glued in actions but this I have not tried.
If you visit the national match forum, there is a discussion about this. One high level shooter uses an old bore guide and a hammer to tap the barrel out. He says it only takes a few whacks and knows what he's talking about. But seriously, you don't need to over think this.

 

[whatsupdoc]

I have pressed out barrels with high temp bearing retainer, but they were seekins with a different barrel nut setup. They have a flat front surface that you can lay them flat on a press and just a little heat and press them out.

Another way I have shimmed the barrel extension is to use bearing retainer to glue a steel shim wrapped around the extension, then after the adhesive has cured freeze the barrel heat the upper and just slide it in.

 

[jelenko]

@LVLAaron How hard is it to remove a barrel after using 609 or 620? Do you need to apply heat?

On advice from others, I'm using a bore guide designed for dedicated 22 uppers. Just a few good whacks with a hammer and the barrel comes out.
With the loctite, the barrel is in there nice and tight - no droop even as the barrel extension comes out 1/2 way.

Others are using a round wood dowel

 

[msalm]

I bed them all after facing the receiver with a mandrel on the lathe. A previous comment on the BAT extensions is spot on, they’re the nicest I’ve used by a wide margin. When chambering the barrel through the headstock, any OEM extension used would often have over a .010” runout after threading on the tenon. BAT’s are always less than .001”, just a wiggle really. I was talking to one of the Army equipment specialists for the M110 rifles and he told me during trials Knight’s Armament had to bed the extensions in order to meet the accuracy requirements of the contract. Having worked on a fair number of them I can say they’re definitely bedded with a semi-transparent epoxy. Looks like acraglass gel, but no way of knowing.

 

[DangerRanger]

Unfortunately I called BAT yesterday and Steve said they no longer make them.

 

[jelenko]

WOA sells the barrel extensions that they use. Their extensions are longer than standard and. I believe have a larger diameter than standard.

https://www.whiteoakarmament.com/competition-barrel-extension-m4.html

They also sell a builders kit with 18 extensions. I think the threads on the extensions are timed differently so the gas port can be in a groove.

 

[ridgeway]

BAT machine used to make them in oversized dimensions. Probably didn't sell many cause the milspec production ones are fraction of the cost and most of AR crowd could care less about fit or quality. If you can dump a 30 round mag without malfunction, that all that matters, lol. Me, I still single feed my precision AR, lol

 

[msalm]

Unfortunately I called BAT yesterday and Steve said they no longer make them.

I still have 4 or 5 unused ones ,if you want one PM me

 

[DangerRanger]

I still have 4 or 5 unused ones ,if you want one PM me

Thanks for the offer. I’ll talk with CLE about it