Shims between
- Thread starter MGYSGT
- Start date
Varminterror
New member
steve garrett
Active member
Why not make the shims go between the barrel nut and the outer shoulder of the barrel extension. I am not too keen on putting them between the upper and the extension
Originally Posted By: steve garrettWhy not make the shims go between the barrel nut and the outer shoulder of the barrel extension. I am not too keen on putting them between the upper and the extension
They do go between the extension and barrel nut. That is also what the OP said.
They do go between the extension and barrel nut. That is also what the OP said.
steve garrett
Active member
Originally Posted By: reb8600Originally Posted By: steve garrettWhy not make the shims go between the barrel nut and the outer shoulder of the barrel extension. I am not too keen on putting them between the upper and the extension
They do go between the extension and barrel nut. That is also what the OP said.
I know that, the interface between the barrel extension shoulder and the front edge of the upper IMO is a critical interface. I know mike from dtech actually trues this area of the upper. I don't see why you couldn't slip these over the muzzle end of the barrel and just use the barrel nut to the outer edge of the barrel extension for your interface. this way they would also not need to be cut either.
They do go between the extension and barrel nut. That is also what the OP said.
I know that, the interface between the barrel extension shoulder and the front edge of the upper IMO is a critical interface. I know mike from dtech actually trues this area of the upper. I don't see why you couldn't slip these over the muzzle end of the barrel and just use the barrel nut to the outer edge of the barrel extension for your interface. this way they would also not need to be cut either.
Varminterror
New member
I have always placed the shims between the extension flange and the receiver, not the barrel nut.
I was instructed to do it that way, then learned the hard way to do so when I ignored those instructions, because the shims aren't very robust, and it's not that hard to pinch one out of alignment when you torque the barrel down.
If you buy shims produced from shim-stock, they will retain the "trueness" of the receiver extension. For what it's worth, the whole [beeep] thing has to be true together. If the barrel nut isn't true to the extension, it will produce uneven pressure between the barrel extension flange and the receiver, just as if the receiver wasn't true anyway.
I was instructed to do it that way, then learned the hard way to do so when I ignored those instructions, because the shims aren't very robust, and it's not that hard to pinch one out of alignment when you torque the barrel down.
If you buy shims produced from shim-stock, they will retain the "trueness" of the receiver extension. For what it's worth, the whole [beeep] thing has to be true together. If the barrel nut isn't true to the extension, it will produce uneven pressure between the barrel extension flange and the receiver, just as if the receiver wasn't true anyway.