Difference between Picatinny rail M-lok and KeyMod?

Hello colleagues,

I apologize for the noob question, but what's the difference between Picatinny rail M-lok and KeyMod?

I bought a bipod for my Taipan Veteran Long .25 made by a colleague from Russia and now I have to pick up picatinny rail.

I have no experience and I wonder what to choose. Brands are expensive and there is variety in AliExpress, but I want not to make a mistake because delivery to Bulgaria is a very long time.

Apart from the difference between M-lok and KeyMod, I see that there is a difference between the width of 20 and 21 mm?

Please let me explain what is the difference and not offer me a ready option.

Thanks in advance!


 
Whereas the earlier Weaver rail is modified from a low, wide dovetail rail, the Picatinny rail has a more pronounced angular section.[citation needed] Designed to mount heavy sights of various kinds, a great variety of accessories and attachments are now available and the rails are no longer confined to the rear upper surface (receiver) of long arms but are either fitted to or machine milled into the upper, side or lower surfaces of all manner of weapons from crossbows to pistols and long arms up to and including anti-materiel rifles.[citation needed]

The only significant difference between the Picatinny rail and the similar Weaver rail are the size and shapes of the slots, where the Picatinny rail has square-bottomed slots while Weaver rails have rounded slots.[citation needed] This means that an accessory designed for a Weaver rail will fit onto a Picatinny rail whereas the opposite might not be possible (unless the slots in the Weaver rail are modified to have square bottoms.)[citation needed]

Weaver rails have a slot width of 0.180 in (4.57 mm), but are not necessarily consistent in the spacing of slot centers.[8] While some accessories are designed to fit on both Weaver and Picatinny rails, most Picatinny devices will not fit on Weaver rails. From May 2012, most mounting rails are cut to Picatinny standards.[citation needed] Many accessories can be secured to a rail with a single spring-loaded retaining pin.
 
I just went through this myself . I wasn't thinking clearly and ordered an Mlok picatinny rail section. The problem is these are made for AR hanguards and have a protrusion on the bottom side that fits in the holes on the AR hanguards. Since I had it and didn't want to wait to order the correct one I just filed it off flat then mounted it on my Veteran. You need to order one that is just a flat bottom mount.
 
Thanks for the reply!

And I came to the conclusion that the base should be flat and whether it would be M-lok or KeyMod - it is important for firearms depending on the type of rail they are made of.

It matters how you grip the picatinny rail to the rifle. Whether with screws and nuts or with a screw for wood. Those that are bought in a set with rail I think they do not happen because they are for firearms.

I have the following question - how thick is the stock in place where the picatinny rail is mounted? (Taipan Veteran Long .25) 

Also the stock in the back if it is dense? My thought is to put a hook on a belt?
 
The wood is plenty thick in the fore end and I countersunk the holes for the nuts on the inside so they sit below the surface. As for a sling I went with a single point with the loop mounted on the scope rail.

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Thanks Randy. I'm also thinking of milling holes for nuts inside and out of screws with a profile "hidden" head.

Rail will be from AliExpress. I will take it for a long (for example, 5 ") and I will put it besides the bipod for example "WIPSON Aluminum Adapter Set 20mm Rail Mount Base Quick-Detach 1-1 / 4 Push Button Sling Swivel Picatinny Connecting Sling Ring" by AliExpress.

Then I'll put "Tactical Multi-function Gun Rope Military Portable Strapping Belt for Shotgun Airsoft Bundle Gun Belt Hunting" again from AliExpress.

This grip on the gun rail I do not like anything ...