LMT MRP compatibility issue with non-LMT lower

[MAD750]

I purchased an LMT MRP upper for my non-LMT lower. It will not fit onto my lower. The bosses on the lower that are drilled for the pivot pin have too much material around the hole and it contacts the upper before the pin holes line up. This is the second upper (LMT exchanged the first on my nickel) and LMT stated that it fits their lowers.

Has anyone else had this come up before?

[pacrimguru]

what are "the bosses"?

my MRP upper has some extra material on the lower edges of each side of the upper making it hard to get on. i have to put some weight on it and lightly tap the pins with a hammer to get the upper mounted. LMT does this to make the rifle very solid.

[MAD750]

what are "the bosses"?

The two circular lumps of material that are drilled for the pivot pin.

In my discussions with LMT they didn't feel any force should be required. You should be able to assemble the two parts by hand.

In my situation the only way it will fit is if material is removed from one or the other of the two halves.

[asheron2]

Sure the lower isn't what's out of spec?

[SJgunguy24]

Sure the lower isn't what's out of spec?

I'm 99.999% positive this gun was in the shop today. That lower fit a number of other uppers, including other LMT uppers. The "quick change" barrel feature adds material and just makes the fitup super tight. So tight we couldn't get it on. It was close but far enough to not want to force the issue.

[tenpercentfirearms]

If you are dropping that kind of cash on a LMT MRP upper, why not just buy another lower. Not necessarily LMT, but go to that shop and test fit some lowers first and then buy them. It might be easier than trying to blindly get an upper that fits from LMT.

Or ask LMT if you can send your lower to them for them to test fit the uppers and then send it back. They are an 07 FFL so they legally can accept it from you and ship it back to you.

[MAD750]

Sure the lower isn't what's out of spec?

I'm 99.999% positive this gun was in the shop today. That lower fit a number of other uppers, including other LMT uppers. The "quick change" barrel feature adds material and just makes the fitup super tight. So tight we couldn't get it on. It was close but far enough to not want to force the issue.

[Forewarned]

My MRP fits in my DSA lower nice and snug. I have to squeeze the upper and lower together to get the rear pin out, and even then I can't do it without a punch.

[asheron2]

My MRP fits my : Mega, Sun Devil, Cavalry Arms, and 80%. So if the lower is to spec than the upper must be whats wrong.............

[dascoyne]

My MRP had no problem with Colt or Mega.

[MAD750]

[asheron2]

You should get a product that works good because you spent the $$.

If you want to avoid buying another lower, just take a file to you current lower(if its a cheap one). This will save you money immediately and a lower receiver really isnt that expensive.