Rifle receiver extension distortion

[Amicus]

I put together a lower for a training rifle, so first tier parts were not necessary. At least, that's what I thought. I used a DPMS receiver extension and, at proper torque values (35-39 ft. lbs.) the wrench flats distorted significantly. If I pull this sucker off, I will probably not be able to reinstall it.

Reportedly, some other less-expensive REs have had this problem.

Same tools and techniques as with other builds, but I previously had a supply of Colt receiver extensions and have never had this happen. (I know, you get what you pay for).

Does anyone know of a decent "middle tier" rifle receiver extension that does not lose its shape when properly torqued?

[Iraqgunz]

No idea what you paid for it or what they cost, but Apex Gun Parts in Colorado has some Colt kits they are selling. Here is the link for the RE. https://www.apexgunparts.com/product_info.php/cPath/49/products_id/1371

I put together a lower for a training rifle, so first tier parts were not necessary. At least, that's what I thought. I used a DPMS receiver extension and, at proper torque values (35-39 ft. lbs.) the wrench flats distorted significantly. If I pull this sucker off, I will probably not be able to reinstall it.

Reportedly, some other less-expensive REs have had this problem.

Same tools and techniques as with other builds, but I previously had a supply of Colt receiver extensions and have never had this happen. (I know, you get what you pay for).

Does anyone know of a decent "middle tier" rifle receiver extension that does not lose its shape when properly torqued?

[MK18Pilot]

Since you used the term wrench flats, we must be talking about a fixed stock receiver extension.

The wrench flats are for emergency use only. A collet or V-blocks should be used to tighten the receiver extension. The problem is, the tools are expensive.

The low end extensions are made from 6061 versus the Colt's which are 7075. Aluminum will always lose a fight against a steel wrench.

[Amicus]

No idea what you paid for it or what they cost, but Apex Gun Parts in Colorado has some Colt kits they are selling. Here is the link for the RE. https://www.apexgunparts.com/product_info.php/cPath/49/products_id/1371

Thanks. I will look into that. From my experience, any used Colt RE is better than the new POS I installed yesterday.

Since you used the term wrench flats, we must be talking about a fixed stock receiver extension.

The wrench flats are for emergency use only. A collet or V-blocks should be used to tighten the receiver extension. The problem is, the tools are expensive.

The low end extensions are made from 6061 versus the Colt's which are 7075. Aluminum will always lose a fight against a steel wrench.

You learn something new ... I've known so many folks who use the wrench flats, I thought nothing of better tooling. I have tried to use the best tools for the job I can find, if you can find them through Brownells or a good hardware source. Any idea as to how I can find a source for such collet? Even if it is just to say "Whew, that's more than I can sink into this."

[markm]

The APEXGUNPARTS are a steal.

Gunz... quite posting that link. That's my secret stash for COLT PARTS!! ;)

[GTifosi]

If collets or V-blocks aren't available or too expensive, using a crowsfoot open end wrench on a torque wrench isn't too bad.
The fit will be better than a good %~age of armorers wrenches at least, as those are made to fit 'all' regardless of them being at the high or low end of the tolerance spectrum.
At least with the crowsfoot you can have a few 64's to juggle around for a better fit.

Barring that, a strap wrench isn't such a bad thing, but modifying it for use with a torque wrench can be a bit of a bugger.