-First off, does anyone know if the E3 bolt (which has dual extractor springs), by chance uses the same springs that an LMT enhanced bolt uses? I have lots of the LMT springs which I’d hate to let sit, if my buddy can use on his new E3 mod1.
-Secondly, I’m also wondering if anyone has found a way to stake the mod1’s castle nut, considering the new style nut kac uses does not have any “slots” where any staking could even be done. Solutions? Trying to decide if a Colt castle nut is in order, but thought I’d ask if anyone else has chosen to tackle this task on their mod1? Are the mod1 nuts loctited on? Anyone???
There is no need to stake the castle nut. I have yet to see one shoot loose, and should you need to pull it, a bit of time under a heat gun will get it off the receiver with no damage to any parts. You can certainly replace it if you really want to stake your castle nut, but there is no “need” to do so.
Typos brought to you via Tapatalk and autocorrect.
Jack, I hear where you’re coming from, and I fully realize some guys do not care about staking. I would like to further ask you, is there anything proprietary or “special” about the mod1’s receiver extension, or end plate?? IOW’s if one were to install a Colt/etc receiver extension , castle nut, and end plate, would it work just fine, or no??? IIRC, I believe I once read something about the kac receiver extensions indexing themselves perfectly, which led me to think they might possibly be proprietary, but that’s just a hunch . Thanks for your help.
Hey Razor, the RE is a standard mil spec extension. KAC applies some serious torque when installing the castle nut and I’ve never heard of one coming loose. They DO NOT loctite them on. I swapped out an end plate last night on an E3 lower I bought last year and it required some muscle to break loose. My lower had a GI castle nut, so I staked it when I was done. If it’s a factory installed nut, I wouldn’t sweat it. If you decide to swap the end plate, just replace the castle nut at the same time and stake her down.
I’ve got a guntec armorers wrench that has a single “pin” engagement point, so IOW’s its only going to engage one single hole in the kac castle nut. Is there a better option for an armorers wrench, one that might possibly engage two or three pin holes simultaneously?? I’ve always gotten by with the Guntec wrench, but I’ve often wondered if there is a better wrench choice , especially with regards to these unique kac bbl nuts…??
The extractor springs on the LMT Enhanced bolt and the KAC E3 Bolt are not the same.
Here is a picture of both bolts disassembled.
LMT Enhanced and spring on the left with KAC E3 and spring on the right
the LMT spring is a little wider (girth) and shorter while the KAC spring is thinner and longer.
As for the the KAC Mod1 castle nut. It’s the old style nut, not sure why KAC went with that. It does not have loctite on the threads, but is extremely difficult to get off, I ended up shearing off the lug on my wrench. thank god it has a replaceable lug (brownells). I ended up using a 3/8 punch that i replaced as the lug in the wrench and a heat gun to get off the Mod1 castle nut, ended up damaging the nut in process. I got a colt castle nut i used to replace it with though.
Also, you can use a standard milspec RE with the Mod1, however the KAC buffer tube has a notch that catches on the buffer retaining pin to help align the tube.
The Hammerhead won’t work on an SR-15 castle nut because it doesn’t have any notches to lock into. Here’s a couple of pics I borrowed from the KAC picture thread.
Very necro but thank you for answering my question. I figured it would be more appropriate to add it to this thread rather than cluttering things up by starting a new thread.
