I’ve got a Atacr 4-16x42 mounted in 1.26” rings on a mk12 mod 0. I’m looking for an offset mount to use with a Holosun scrs. I’d like to find an offset that’s lower than the arisaka offset. So I’ve been looking at the Trex offset, the Strike industries ambush 45, and the pri rmr offset as possible options. Obviously I’d have to use a c&h 509t to rmr adapter.

Does anyone have experience with the trex, strike industries, or pri offset? I like the idea behind the strike, but not sure on durability.

If there is a direct 509t offset mount that I’m not aware of (other than the arisaka) let me know.

I realize now exactly what you're asking, but with ring height that short, I'd go top mount. Buy one of those RMR mounts that clamp around the tube of the scope and call it a day

The Arisaka sits higher as they made it align with the bore of an AR. It’s my understanding the T-Rex doesn't, causing complications with zeroing and hold overs. I haven’t tried one myself, but that was why I skipped it.

I wouldn’t buy anything from Strike Industries.

Interesting. I was under the impression it’s higher so it will match the 1.5” scope height so you don’t need to lift your head when repositioning.

Yea I’ve been hesitant on the strike purely due to all the colorful stuff in their line up. No idea on quality.

Well the problem is there is a lack of 34mm rmr tube mounts.  Essentially the taller larue is the only option… other than maybe doing a aimpoint pic rail.  

Another thing to note is that this is on mod 0, so it’s got a full length rail/riser that raises the receiver height up .450”.  So even with the lower offsets like the trex, strike or pri, it’s not like it’s going to be low per se.    so .450” of the rail + 1.26” rings = the scope being 1.71” over bore.. due to this a 45 mount really feels better and easier to use.

That’s part of it but I’d say the Arisaka could be trimmed down another quarter inch at least. I have a Poortex Venom which rides pretty low and I can still crunch down enough the dot can go out of view.

And having the ARMS riser sleeve I think the PRI might be your best bet. Didn’t consider the added height there which is going to mess up your bore axis alignment no matter what. So my biggest knock against the T-Rex isn’t valid here either.

Ordered the pri 45 and 509t-rmr adapter. I’ll update thread once they come in and I get the scrs mounted.

Update:  the C&H 509t to Rmr adapter will not fit the scrs using a rmr mount. It orients the sight backwards. .

See the pics below. The c&h plate is different on both sides of the ‘dove tail’ (one edge is straight angled and the other is slightly milled as it should be). The issue with it is that due to the c&h plate not having both edged milled off correctly the sight will only work in one direction and it is oriented backwards on a rmr mount.

Here is the c&h

Attached File
Attached File


Here is the stock Holosun mount. Notice how they aren’t milled to a point on both sides.

Attached File
Attached File



Guess I’ll call c&h tomorrow for a refund… probably have to return the pri 45 as well as I don’t know of any other 509t to rmr adapter available.

That sucks. I’d avoid doing business with C&H beyond this too. They’re selling rebadged Vector Optic stuff for massive profits. This looks like the same cut that comes on the Vector mail box red dots.

Would the plate that I received even work on a 509t and have it oriented correctly?

Yea it sucks. I’ll have to return the c&h.. take an ass beating returning the pri 45. Then find a lower 45 pic mount and buy a 509t to pic adapter.

I will say the SCRS is an impressive little sight.

Haven’t contacted c&h yet. I did mock everything up today just to see if the cant and height will work.. and man does it work great.

Going to contact c&h in the morning to see if this plate was a defect. If it is I’ll exchange, if it’s how they are I will return and buy the slightly thicker Holosun plate.

Nice! Hopefully they can get it worked out.

@-OdieGreen-   @Duck_Hunt  I've got the Trex offset for a holosun 508t for using with nods, I used it side by side with my buddy running an rmr on a arisaka & the rmr/arisaka seemed easier to pickup without ducking my head.  We didn't measure, but it felt easier.    That being said my holosun is zero'd for 50m for nods use only.  I know its not ideal, but with nods the odds of me shooting farther than that are pretty slim.  If you're willing  

Duck, check out reptilia as they offer mounts that clamp around the barrel & offer you full rotation of it.  Not sure how 1.26" rings works to MM, but they have options.   If you're willing to sell your current rings they also offer a scope base & a upper clamp that is set for assorted micro sights.

https://reptiliacorp.com/product/trijicon-rmr-rof-sar/

I actually had a reptilia.. but the 1.5” height plus the .450 height of the pri rail made it way too high.  

I almost went with the trex but decided not to due to it being 35 degrees as I was worried about it clearing the large windage turret on the Atacr especially since it’s mounted in 1.26” rings. When I mocked up with the PRI 45 it was absolutely perfect as the windage knob just barely misses the window of the scrs.

Started a return on the c&h and explained the issue on the form (they don’t take calls).. just waiting on them to ‘review’ now.

Here is the response from c&h.  

‘Hi,
Only one side is chamfered as it's designed for the 509T and not the SCRS. If you'd like to return it, you can get a return shipping label directly from our website here: https://chpws.com/gear/warranty-return-policy/‘

Sending back for refund.