I'll try to keep it as short as possible.

About a year-and-a-half ago I completed my build.  14-1/2" barrel with pinned flash hider.  10-1/2" MI SSM (low-profile) handguard.  This Christmas I received an Inforce WML and Magpul Offset Light/Optic Mount.  (I chose them.)  Went to put mount and light on, yesterday.  Oops!  Magpul MBUS Pro doesn't clear the mount and the back of the light is further back than I'd like.

Here's what it looks like:





I'm wondering if the Arisaka M-LOK Offset Picatinny Mount will allow me to move the light a bit down and forward, as opposed to what the Magpul mount does?  It looks like it.  Otherwise it's replace the handguard.  MI has discontinued that model, but, they pointed me to somebody that still has 12" versions in stock.  I'd prefer not to have to spend the $180 + shipping, though, if I can avoid it.

Thanks!

I don't think you are going to gain much with the Arisaka mount over the Magpul.  It might get the light to where it clears the sight, but it will still sit the light in roughly the same spot along the rail, assuming you want it more forward.  The Arson Machine Offset mount would get the light out a bit further and would probably also clear the front sight, but it is not a 45° mount so it would put the light in a bit different position.

Thanks for the follow-up, Sortafast.


Yes, I've been talking with Arson.  Not certain I like the position the light would be in with their mount.

I think the Arisaka would move it about as far forward as the Arson.  Here's a picture I culled from Arisaka's product page:



I calculate it'd more the light forward by about 1/2 inch?

And, as you noted, I think the Arisaka will allow me to move it far enough away from the top rail to get the MBUS Pro back in front... maybe?

It looks like the Arisaka would afford you the clearance for the front sight, but the Arson mount would put the light further forward and also clear the front sight.  With the Arson mount, the picatinny rail starts at the front screw where as the Arisaka it starts at the rear screw.  So the Arson looks to gain you roughly 2 slots more in forward placement, if that makes sense.  As for the angle between the 2, I couldn't tell you which is better.  Different strokes and all.

If you mount the front sight backwards, will that give you clearance?

It would seem that way, but, my contact at Arson seemed to be unsure of that.


In retrospect: I think you're right.  That's about another 1/2 inch.


That's the thing.  I'm not certain having the switch "up top," as it were, as opposed to at a 45° angle, would be better.  Trying to emulate what the handling would be like, with the light as it's currently mounted.  Seems awkward.  Arson states "Why 90°and not 45° you may ask?  In developing this mount we found it to be more comfortable to actuate the light as well as it places the light closer to the centerline of the host rail system."  I'm not seeing it.

Not with the current mount.  No.

You can always ask how Arson came to that conclusion.

Asked.

I suspect what they're claiming might be true of a light with a rear-facing switch, or with an external switch pad, but, with the Inforce WML that would place the switch on top.

It just occurred to me last night: I have a buddy that has his own machine shop.  He has a CNC and a bunch of other stuff.  He's always looking for things to make (outside of the regular contact work he gets).  Maybe I'll ring him up.  Point him to the Arisaka, Arson and Magpul products and tell him "It needs this feature from this product, this feature from that one, and this feature from the other?"  Give him my Magpul mount for dimensioning.

Check out the Monkey Bar:

http://www.unitytactical.com/shop/fusion-monkey-bar/

Instead of spending all that money to put a picatinny mount back onto a MLOK rail... why not just get a Scout and get a better light, clearance, and lower weight all in one swoop?

Thanks for the suggestion.

Looks like a lot of lever arm hanging off that one small attachment point.  Dunno.

"All that money?"  Spend maybe $50 for a solution for the light I have vs. spend $300 to $400 on a Scout?

Thanks for the suggestion, but, no.

Problem solved with a Magpul Cantilever Rail/Light Mount, Aluminum, M-LOK:



Ended-up looking like this:



It's a bit further off the rail than I'd like, but, being as it had to clear the forward QD socket: Not much could be done, there.  (As you can see: There's little clearance, as it is.)




It's about as far forward as I'd like. Any further forward and I'd start worrying about flash catching the lens.  (And the light clearing the underside of the barrel rest in the safe.)

Only down-side is I lose that forward QD attachment point for when I want to move the sling so I can carry the rifle on my back.  I'm sure I can work something out.

Thanks again, everybody, for your suggestions.