M2 Tactical Receiver Plug Screws

[CTNZ]

Hi All,

 

I have a M2 Tactical which has 4 holes drilled in the receiver for a weaver rail and another couple of holes for the rear ghost ring sight. I'm wanting to source some plug screws for these holes for when I swap out the barrel to a field one for duck shooting.

 

Currently the 4 holes for the rail have the plastic plugs in them from the factory but i'd still like to get actual plug screws in case I use a rail at some point then want to remove it. According to this thread the holes on an M4 are metric M4x.75 not SAE #8-40. Is this the same for the M2? And also are the two holes for the ghost ring sight the same size as the 4 for the rail?

 

Has anybody found a source for plug screws that are the correct size? I sent Benelli CS a query about this and asked for exact thread size and whether they have plug screws and all I got in response was "Most people will use a crew and grind it off flush on the inside." Which didn't really answer any of my questions. You would think they would stock these screws.

 

CT

[CTNZ]

Update: I probed Benelli USA a bit further and asked "Do you know the exact thread size/pitch of the mounting holes on the M2? If I know that I can make my own plugs from screws."

 

Their response was: "We use the 8-40 threads"

 

I'm not sure if the CS rep is saying that the threads in the M2 reciver are actually 8-40 not M4x.75 or that they just use 8-40 plug screws. It would be good to have a definitive answer so i've sent a query to Benelli Italy.

 

CT

[benelliwerkes]

Both screw sizes work if those M2 receiver holes were factory and not uncertain aftermarket installations. There is only 0.0065" of a major diameter difference between the 8-40 and the M4. The .75 pitch and 40 tpi are also virtually identical. It is one of few size instances where metric and UNC/UNF are interchangeable for all practical reasons. I have used both in the receiver holes.

 

You can get the 8-40 plug screws @ Brownells.

 

https://www.brownells.com/gunsmith-tools-supplies/small-hardware/metal-screws/plug-screw-kit-prod792.aspx

 

 

These are factory screws from years past.

Edited October 17, 2017 by benelliwerkes

[CTNZ]

Thanks for your response benelliwerkes. I just received a response from benelli Italy and they said the factory holes in my M2 Tactical receiver are in fact 8-40 NS2. I'm not sure what the NS2 stands for. That goes against the reports i've read in this forum that they are M4 x .75 although those claims were in regards to a benelli M4 not an M2. Maybe they are different or maybe they have recently changed to 8-40 as those screws are more common...