My barrel fit loosly as well, I tried a couple different ones and it was the same for all of them. Didn't really think much of it as they tightened up just fine with the barrel nut.
My barrel fit loosly as well, I tried a couple different ones and it was the same for all of them. Didn't really think much of it as they tightened up just fine with the barrel nut.
It still fits the Ms upper. Every dimension on the uppers are checked after they get them back from ano and if it's not within spec they don't ship it out. Tolerance stacking is a problem. If you have a barrel extension on the small side and an upper on the bigger side of the tolerance its going to be loose. If you are worried about it send it back to atrs and get them to double check it with your barrel.
There is no safety concern in regards to what you are describing. If a tighter fit is desired I have heard from some folks that they bed their barrel extension into all upper receivers using loctite 620. This is not a method that I have experience using myself, and am merely passing along a customers recommendation. Use at your own risk. [Although I am told there is no risk]
The green loctite 620 isn't a thread locker, it's a retaining compound designed for cylindrical applications, seems perfect. We use this stuff at work all the time, it will fill a gap of 0.015.
I never thought of using it, but I will definitely "borrow" a few drops from work if needed for my barrel/upper.
"This year will go down in history. For the first time, a civilized nation has full gun registration! Our streets will be safer, our police more efficient, and the world will follow our lead into the future."
Adolf Hitler, 1935
Not seeing many builds, lets see more photos guys.
-Robbie L
"Mk12 mod 1" Modern SPRter
ATRS MS receiver
Custom ATRS SPR barrel 18.6"
Ops Inc. 12th Collar and brake
DD mk12 gas block
Knights Armament mk12 mod 1 free float RAS
Knights Armament flip up M4 front sight
Knights Armament folding micro rear sight
PRI M84 gas buster charging handle
LMT FA BCG
Larue Tactical LT104 QD SPR mount
Nightforce NXS 2.5-10x24 MD
ARMS #32 Bipod Mount
Harris Engineering BRM-S w/ KWM Pod-Loc
KAC hand stop
VLTOR A5 buffer system
B5 Sopmod stock
KAC end plate sling mount
ERGO grip
Geissele SSA-E trigger
Geissele LPK
Non Restricted!