Fitment concerns

[washguy]

Wzrd       Hell Yes !   way to go  !             Wash

[Wzrd]

I just noticed in my photos that my muzzle brake came loose & must've twisted while I was shooting. I have it installed with a jam nut so it's easy to index & easily removed/reinstalled for when I eventually get my suppressor out of purgatory. Does anyone have any suggestions for how to keep it from coming loose while still allowing it to be easily removed when necessary? Did I just not tighten the jam nut sufficiently? Should I post this elsewhere or read an existing thread?

[jtallen83]

Rocksett works good with high temp applications. Just soak it overnight in water and it will turn right off. That is what AAC supplies with their brakes.

[392heminut]

On 6/8/2017 at 4:00 PM, jtallen83 said:

Rocksett works good with high temp applications. Just soak it overnight in water and it will turn right off. That is what AAC supplies with their brakes.

^^^^^^That right there! It's weird but the stuff actually does turn loose after being soaked in water. It's the only thing I use on muzzle devices now.

[Wzrd]

So I couldn’t leave well enough alone & have new problems & questions. I “upgraded” my BCG to a Lantac 308 Heavy E-BCG. The idea was to use my original KAK BCG in a new 80% 308 build & use the Lantac in this build which I plan to shoot suppressed a lot. (The Lantac supposedly being designed with suppressed shooting in mind). I’ll try as best I can to describe the problem I’m experiencing: I haven’t shot the gun with the Lantac bc when I cycle it by hand it is binding inside the upper &/or buffer tube & actually gets stuck. A slap on the side of the upper is enough to unstick it & send the BCG into battery. The odd thing is if I cycle it with the takedown pin out it doesn’t get stuck but it’s forcing the receivers apart by approximately 1/32-1/64”. This never happened with the KAK. Perhaps the Lantac isn’t compatible with my receivers? I have a PWS anti-tilt buffer tube despite using a DI system. I’m wondering if that might be causing a problem but I don’t see why it would. I will contact Spike’s & Lantac to see if they have any insights. I’m including some photos showing measurements of the rear end & widest section of my two BCGs (the black is KAK, silver Lantac). I’ve also noticed inside my upper there is a small ridge. It seems almost like the machining stopped halfway through its last pass & didn’t finish the rear of the upper. You can see in the photo where it’s being worn. I can see on my KAK where it was rubbing on this spot but no evidence thus far on the Lantac. However this is my only 308 build so I’m not familiar with all the nuances of the pattern(s). I just know none of my ar15s have ridges like that inside their uppers. Any help is greatly appreciated. Ultimately I may just have to go back to the KAK. I’ll update with any info from Spike's or Lantac. 

[washguy]

Wzrd     why don't you take a dremel and smooth out that rough spot on the inside of your receiver? That would be my first thing to do.Second would be to use a plain ol buffer tube and buffer...you could even use one off an ar15 just to see if the bcg  slides back and forth without catching. But if it were me I would send it back so fast it would make your head spin...ill bet it costs you some bills. Once you start messing with it you own it....If your rifle was working real nice before this....put it back like it was and get your money back from the bcg....   Wash 

so this quote is from lantec  "The flared boss at the tail of the carrier enhances the BCG's position within the buffer tube at the time of cycling and allows for a flatter more controlled reciprocation of the assembly"  ill bet your enhanced non tilt whirley dirly buffer assembly is not playing nice with the enhanced lantic butt flared tail....do you see the problem?...its the word enhanced....lol   when a company really cant make anything on their own that is really something new....they rig up a piece and sell it as enhanced.....lol   you are two for two my brother   Wash

since  ive run out of $hit to do I researched the lantac for you   here ya go...read all the way to the end of the posts...could be the tricky dicky rounded cam pins relationship to carrier/bolt ?   do these m4 guys know anything? hell if I know....they do think nib is from satan....lol....those  ol farts

http://www.m4carbine.net/showthread.php?160543-LANTAC-Enhanced-BCG

Edited December 28, 2017 by washguy

[survivalshop]

    The spot on the Upper Receiver can be dressed up with stones or fine file , it appears to be from the machining process . There are no Mil Spec standards for the 308 AR Builders world , as you know , Tolerance Stacking is a real possibility when using a mixture of components from various manufacturers . 

    The Hammer is more then likely forcing the Receivers apart when Disassembly pin is out . May just mean the two different BCG Manufacturers use different dimensions for their Carriers or it could mean a issue with the Hammer's Travel ark & its hitting the top of the Disconnector in the Trigger assembly & that may only be an issue with the one BCG , be it binding or Hammer interference .

Edited December 28, 2017 by survivalshop

[KS63]

For what you paid for that Spikes receiver, I’d definitely  alert them of that machining step. In no way should that be there. That’s on them.