When it comes to handguards, many, if not most of them, use proprietary barrel nuts. Mil-spec just doesn’t apply to them.I thought the replacement Sig Tread handguards just swap out. No need to remove the barrel nut.
I have the M400 Tread pistol and next step is to replace the handguard, looking for something lighter. I saw some posts where they replaced with another company's handguard like Midwest Industries but had to remove the gas block and use a new barrel nut. Sorry new to AR15 and didn't know SIg uses non mil-spec parts.
So you were able to successfully install a non-sig handguard to your tread?Here is my solution. Had a extra BCM barrel wrench laying around. Just dremeled off the middle prong. Works good!
This hand guards inside diameter is too small! Gas block was touching, resulting in poor accuracy. Watch out any MLOCK accessories may touch the gas bock or gas tube and interfere with accuracy!
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