Simrad 253 scope selection process?...

PlinkIt

GunNut Extraordinaire
Belligerents
Mar 30, 2014
609
83
34
Virginia / North Carolina
I've seen several threads here about the simrad units and appreciate all the info.

I've seen threads showing various ways to modify the 253 & 203 unit to allow use with larger objective or longer scopes than they were interned for example

But

Even though I've noticed several comments stating something to the effect of "once I learned which scopes to use with the simrad it was great".... I've never actually seen much info just listing out the scopes or scope types that work well with these units.

Anything to specifically look for, or look to avoid?
Or lessons learned?
Advice even?
Like magnification ranges that go well with a 253?

Thanks
 

wigwamitus

Sergeant
Belligerents
Jan 5, 2014
2,097
671
219
Wabaunsee, KS
I don't know everything ... but here's what I know so far ...

kn253/kn203 manual says run day scope at 6x to 8x ... says best resolution obtained at these power settings.

I've found the 253 is equally clear up to 12x on the day scope. I've shot it at up to 18x ... it is a bit fuzzy above 12x but I was able to hit 3/4 dots at 100yds.

I'm sure I have not stretched the 253 to the maximum extent of what scopes it can work with.

But I've gotten it to work with the L&S mk6 3-18x T3, the NF 2.5-10x MIL-R and the NF 4-16x T3.

==
Are you trying to decide whether to get a 203 or a 253 !!??

Here are some differences I'm aware of:

253 weight 2.5 pounds
203 weight 3.5 pounds

253 offset 2.75 inches low
203 offset 3.75 inches low

253 max supported day scope magnification 12x (more if you accept some fuzz)
203 max supported day scope magnification 16x (more if you accept some fuzz)

203 has its own rail section on which you could mount an illuminator like the ELIR-3

203 has more flexibility in mounting on larger scopes

==
If maximum flexibility to mount on large scopes is a priority for you, then you would probably prefer the 203.

I like the 253 over the 203 and the PVS-30 due to its lower weight, smaller size and improved ergonmics. I could not reach the PVS-30 focus ring while keeping my eye behind they day scope. That was probably the single most irksome issue for me and the PVS-30. The PVS-30 was also very large and heavy. As large as the 253 looks ... it is smaller and lighter than the PVS-30. The focus knob is very close to the shooter, on the rear of the unit as is the scintillation adjustment knob ... on the rear of the unit, easy to reach.

Of course the main plus over the inline NV clipons like the PVS-30 and PVS-22 is you can move them from gun to gun with no adjustments. Can't do that with the SIMRADs. Set the SIMRAD up for a gun, then you can take it off and remount it to/from that gun. But, if you want to move it to a different gun, then adjustments required. I'm ok with this as long as it is repeatable for the one gun I've set it up for ... and that has been my experience.

Keep asking away, hopefully the experts will show up and help! But the more questions you can ask the easier it will be to help :)
 

PlinkIt

GunNut Extraordinaire
Belligerents
Mar 30, 2014
609
83
34
Virginia / North Carolina
I'm 100% on the 253 at this point, as I don't want the extra size and weight. I know I'm giving up some ability in that decision.

I don't need to go on different guns on a whim, I'm good with the adjustable collimation being required. I might even list that as a bonus after having tried the atn after you guys tried to tell me not to lol

I tried to find a copy of the manual online somewhere that was easy to download, but either my Google sucks or it's not a popular item on the interwebs. Would be good to just read the entire manual before getting my hands on one of them.

Ok so looks like you are sticking around the 40-44 objective

Ok so top end magnification is going to be in the 10-15 range. That's more than enough for anything I'll ever need.

In honesty the 6-8x it says is the ideal is likely all I'll ever need around here.

Is there really a bottom end magnification to these units? I mean can you run it on a 1-8 scope? Or does it really need 1.5-2x for the optical system to come into function
 

wigwamitus

Sergeant
Belligerents
Jan 5, 2014
2,097
671
219
Wabaunsee, KS
PM with manual sent.

I haven't tried anything lower than 2.5x but on any clipon, worst case on 1x .. the clipon image just won't fill your day scope FOV, but otherwise will be totally usable.
 

cake5150

Private
Belligerents
Jan 7, 2014
147
26
34
Fort Wayne, Indiana
I've been using KN203 SIMRADs for about 17 months now. I read a bunch of stuff on them before getting one and have learned some things from experience. First and foremost, I found out pretty quickly that I preferred my KN203 over my PVS-30 so then sold the 30 and bought more SIMRADs. This was mostly because of better passive image performance and easy focus control. Boresighting the SIMRAD and accounting for the height over bore is not difficult. The only part of the manual I don't follow is the last step of zeroing where the user dials out the 3.75" (this is for the KN203) come-up into the dayscope at 100 yd. I leave it parallel and just add 3.75" to my angular solution. For quickness, I just add 4 MOA out to 100 yd, 2 MOA out to 300 yd, then forget about it unless it is a small target. You can also just set up a profile in your ballistic calculator for a SIMRAD equipped rifle, I did that for one of mine.

As far as what day scope to use/not use, I've had good luck w/ all but one I have tried. In general, if the optic's max magnification is 10x or over, buy FFP not SFP so you can still use the reticle effectively. I really want to try a SWFA SS 10x fixed, but don't have one anymore and no family/friends have one either. Having parallax adjustment if magnification is 10x+ is helpful, IMO. MOA or mil based reticle trumps BDC due to having to take into account height over bore for the NV as well as all the reasons it trumps BDC during the day (particularly operative for small targets). Finger adjustable turrets are helpful also, but pretty much any decent scope out there these days will have that. You do not need illuminated reticles for these, I rarely use illumination w/ my SIMRADs. Bottom end of USEFUL scope magnification is ~2x to 2.5x from what I've found, below that you just get tunneling in the image (lower magnification w/o increasing FOV). Some notes are below on scopes I have tried.

Vortex Viper PST Gen 2 3-15x44 FFP: great performance, objective does not fit inside stray light shield (I removed mine anyways for more mounting flexibility). Looking forward to getting this one out to distance, so far only ~300 yd. Passively, good to at least 8-9x. Like Wig said, the manual states 6x-8x for use, but you can go higher depending on lighting conditions. I have found that 8x is about perfect for shooting passively, and realistically it is all I need anyawys. I can't overstate how much better the KN203 was passively than the PVS-30s I owned and used. Huge lenses gonna huge lens I guess.

Vortex Viper HS-LR 2.5-10x32 XLR: great performance, objective was really close on stray light shield, but that was eventually removed for the 3-15 anyways. Observed out to 1000 yd w/ it, shot out to 606 yd w/ it easily (as far as I had dope on that rifle at that time). I have three of these scopes on various rifles, I really like them.

Primary Arms Silver 1-8x24 SFP ACSS: even though it is Chinese glass, this little scope works shockingly well with the SIMRAD as far as image goes. No problem going to 8x despite the tiny objective lens. I don't like that I have no reference points in between BDC marks, but this scope is designed for getting hits on torsos. I know it does it during the daytime out to 800 yd, but haven't gotten to actually shoot this one long distance at night, only observation out to ~500 yd.

Weaver Kaspa Tactical 2.5-10x50: only strike out thus far, image was garbage compared to the others I have tried. I had this cheapo optic on a 22 LR, worked fine during the day but sold it anyways.

I have not tried it on any super high-end scopes, but after I was able to EASILY make out and even measure targets at the 1000 yd line w/ my Vortex 2.5-10x32, I decided I really didn't need to.
 

softcock

novice judgmental prick
Commercial Supporter
Belligerents
Mar 24, 2006
1,108
372
189
Oregon
for ideal scope size ( i thought ? ) they were originally layout for mounting on top of the Mk4 3.5-10 x 40mm , were the Obj would slide just sit inside the pvs9 stray light shield .

( me ) , I Run the simrad with the stray light shield Off, then use a foam beer cozy as a cover in between to keep Dew and dust out at night .
.
 

cake5150

Private
Belligerents
Jan 7, 2014
147
26
34
Fort Wayne, Indiana
One of my KN203 units has a factory accessory rail (I have it oriented to the left side) that is PERFECT for the Radius. Not all KN203s have this accessory, but lots sold in the last couple years do. It all depends on who ordered the unit originally and what options they wanted. The Radius, or any rail-mounted rangefinder that can be boresighted, is really what makes all of this quite compelling for shooting unknown distance, unknown dimension targets. The continuous ranging mode on the Radius paired with a SIMRAD on a suppressed rifle firing a high-BC bullet by someone who knows how to use it truly is something to behold. Honest to God, I don't find myself even wanting illumination the vast majority of the time. That huge lens makes for a bulky package (Ace Ventura reference), but it pays dividends on extremely dark nights.
 

Sixfivesavage

Sergeant
Online Training Access
Belligerents
Mar 30, 2013
1,222
295
189
Maryland
I run a 253 on a 4-16x42 ATACR/18" LMT MRP and a 203 on an AX with a K318I. I'll do some experiments with magnification when I get a chance between the two. Hopefully the humidity subsides soon around here.
 

PlinkIt

GunNut Extraordinaire
Belligerents
Mar 30, 2014
609
83
34
Virginia / North Carolina
PM with manual sent.
Thanks, this gives me some reference. Not as much info in there as I expected though...
I'll read it again today and see if anything else sinks in

...I don't follow is the last step of zeroing where the user dials out the 3.75" (this is for the KN203) come-up into the dayscope at 100 yd. ...
seems like this is a popular method to avoid. I did try plugging the info into ballistic calculator and playing with the height over bore and low zero. Seems fairly straight forward... I'll likely just make myself a chart based on the simrad being attached. Maybe use glow in the dark tape and a marker on my sleeve....

... 10x or over, buy FFP not SFP so you can still use the reticle effectively....
I've already seen the light here. Anything I own higher than 6x at this point is FFP. I do have a 1-5 SFP though.


Having parallax adjustment if magnification is 10x+ is helpful, IMO.
I was already curious about how the focus of the simrad and parallax of the scope may play into one another... So do you mind expanding on why you bring this up? I also didn't notice anything in manual about parallax.

MOA or mil based reticle trumps BDC due to having to take into account height over bore for the NV as well as all the reasons it trumps BDC during the day (particularly operative for small targets).
only bdc items I have left at this point are 1-X items and (as of recently) I only have two Burris XTR2 units with the exposed elevation so I can dial them when I want anyway. They have wind references in mil (SFP on 1-5 & FFP on 1-8) so it'll works out I guess

You do not need illuminated reticles for these, I rarely use illumination w/ my SIMRADs.
that would be nice if the picture is so bright that I don't need illuminated reticle... The units I've tried before could still get the reticle lost when looking into tree lines and such. I do have one of the Leupold mark 5 3.6-18 shorties non illuminated I might could try this on then...

Primary Arms Silver 1-8x24 SFP ACSS... works shockingly well with the SIMRAD ...
This makes me think the xtr2 1-8 may be worth trying then


...I Run the simrad with the stray light shield Off, then use a foam beer cozy as a cover in between to keep Dew and dust out at night ...
Never remember anything referencing a beer cozy as a soft light shield... Thanks for that. This gives me more reason to think it's fine to pull the light shield

... when I get a chance between the two. Hopefully the humidity subsides soon around here...
Thanks, but don't stress it too much. Between humidity, biting flies, and mosquitos... That's why I'm on here and not outside either
 

cake5150

Private
Belligerents
Jan 7, 2014
147
26
34
Fort Wayne, Indiana
I can imagine the thoughts in cakes head

" ... hum ... for tonight should I take unit #15 ? Or maybe unit #7 with the pink panther logo on the side ??" :unsure:
Haha, yeah but I'm down to less than five now :) Funny thing is, I used to own a super nice AN/PAS-13G LWTS but wound up selling it since I moved back to the midwest and out of hog territory. I just didn't use it anymore. I now use these old SIMRADs no joke fifty times more than I ever used that thing. The picture is disproportionately fantastic for the $$ spent. Yep, it is much heavier but IDing and shooting what I am looking at beyond 500 yd is stupid simple with these. I've been "in between" thermals for over a year now but I am waiting on a great deal for a handheld with a decent sized lens. The 19mm fixed focus bullshit doesn't interest me after having the LWTS for four years.

The parallax can make a difference but usually not a huge one. I do not recall the SIMRAD manual saying anything about parallax either, but I know my PVS-30 manual did. Its guidance was to set the parallax to infinity. Going between the actual target distance and infinity on the parallax dial doesn't seem to affect image focus too much but it does allow you to "tweak" it a bit if you are shooting small targets. Here again is that huge benefit to the SIMRAD over a PVS-30, focus control w/o having to break position. I hated that about my 30, but liked it otherwise. Yes, I suppose a lit reticle may help if looking into shadowy areas, but I just RARELY find the need to use it in conjunction w/ a clip-on. My biggest use for a lit reticle on a FFP scope is at dusk when I am using low magnification, it makes the reticle "pop" when it would otherwise be a relatively small, thin, black set of lines. Bear cozies do indeed work great for stray light shields. I used an old Corona one on my LWTS thermal, it worked like a charm. I had a custom 1913 rail mount made for one of my KN203 units, that makes moving it from gun to gun a WHOLE lot simpler even though the boresight won't be spot on for guns other than the one it was boresighted for. For other guns, I just use the technique outlined in the manual for secondary shooters and that works fine. Tonight will either be 5.56 or 300 Blk subs, but not both... don't need any accidental nighttime kabooms :cool:
 
  • Like
Reactions: wigwamitus

softcock

novice judgmental prick
Commercial Supporter
Belligerents
Mar 24, 2006
1,108
372
189
Oregon
cake5150 said: Primary Arms Silver 1-8x24 SFP ACSS... works shockingly well with the SIMRAD ...
This makes me think the xtr2 1-8 may be worth try
softcock said: ...I Run the simrad with the stray light shield Off, then use a foam beer cozy as a cover in between to keep Dew and dust out at night ...
Never remember anything referencing a beer cozy as a soft light shield... Thanks for that. This gives me more reason to think it's fine to pull the light shield
-
I would just leave shield on unless it it in the way . I have it on right now on mine . but easy to take off when you need .
And the 1-6 and 1-8 by 24 Obj. scope do work surprisingly well . I running a 1-6x24 for long time . lightweight and my favorite day scope on the AR also .

Ya foam beer cooler Cozy's are cheep and easy to trim/cut to fit and flexable as a go-between from NV to scope Obj. .
.
 

wigwamitus

Sergeant
Belligerents
Jan 5, 2014
2,097
671
219
Wabaunsee, KS
@Greensnake

Can you tell us more details please?

Is that the 10mm spacer ?

Looks like the 253 is mounted fairly far forward on the SIMRAD mount. Where there any mods to the mount ?

And looks like the light shade is removed.

Anything else involved ??

Thanks !!
 

Greensnake

All Your Base Are Belong To Us
Belligerents
Feb 17, 2017
82
12
22
51
Cleveland, GA
@wigwamitus

Scope is mounted as far to the rear in the Spuhr mount as possible without damaging the scope. It is a 10mm spacer. Sunshade removed. Does make slight contact with bell of scope when mounting, front not top, so I have to be careful and use a cloth or something between the two when mounting. Once mounted, makes no contact when shooting. It is a very tight fit.
 
  • Like
Reactions: wigwamitus

wigwamitus

Sergeant
Belligerents
Jan 5, 2014
2,097
671
219
Wabaunsee, KS
The Spuhr ISMS mounting system has a ZILLION optional attachments.

And for the SIMRAD (US) Mount there are both 4mm and 10mm spacers. These allow the SIMRAD mount to get up higher and allow the SIMRAD to "reach over" larger objective bells. Mile High is the USA distributor for Spuhr, so you can view most of the options there and also view them on Spuhr site itself. For the items that Optics Planet has, you can usually get a lower price with OP.
 

PlinkIt

GunNut Extraordinaire
Belligerents
Mar 30, 2014
609
83
34
Virginia / North Carolina
See I thought I was missing something about the mounts until you said that

Then it dawned on me after your post... The spacers you guys are referring to have nothing to do with the simrad mount

Trip back to mile high
4mm
10mm

So I see what you are doing now.

Does this offset give you guys any trouble?

Also I noticed the simrad mount references that it's for 34mm mounts... So I guess there is no option for a 35mm mount?.. I would have thought it would work with either
 

wigwamitus

Sergeant
Belligerents
Jan 5, 2014
2,097
671
219
Wabaunsee, KS
The hard case I have says "SPA Defense" and includes this website ...

http://www.spa-defense.com/

But that website has been "recycled".

So it looks like the US entity that made them has, hum, been "transformed". :)

So the answer from me is "no".

Is there a problem needing to be worked on ??

At these prices, perhaps when they get bad broke, we toss 'em in the trash and buy a new one ??
 

upSLIDEdown

Private
Belligerents
May 12, 2014
35
1
12
The hard case I have says "SPA Defense" and includes this website ...

http://www.spa-defense.com/

But that website has been "recycled".

So it looks like the US entity that made them has, hum, been "transformed". :)

So the answer from me is "no".

Is there a problem needing to be worked on ??

At these prices, perhaps when they get bad broke, we toss 'em in the trash and buy a new one ??
Lol yeah, I tried them a year ago or more with a number I found. Wasn't much help. Yeah, I've got one that's on the fritz. Semi-certain it's the power supply inside the unit. Sometimes it works. Sometimes it doesn't. Just didn't know if anyone in here knew of anyone that had been inside one.
 

wigwamitus

Sergeant
Belligerents
Jan 5, 2014
2,097
671
219
Wabaunsee, KS
Well @redneckbmxer24 and @Killswitch Engage are the two SIMRAD heavies around here, so if either of them show up, they'd be most likely to have been inside or know someone who has.

Power issue sounds at least mildly promising. I've had power issues on other sorts of clipons that have been solved. Have you tried to investigate the battery compartment as a possible issue source ?
 

upSLIDEdown

Private
Belligerents
May 12, 2014
35
1
12
Well @redneckbmxer24 and @Killswitch Engage are the two SIMRAD heavies around here, so if either of them show up, they'd be most likely to have been inside or know someone who has.

Power issue sounds at least mildly promising. I've had power issues on other sorts of clipons that have been solved. Have you tried to investigate the battery compartment as a possible issue source ?
Lol, yeah Killswitch has already had it and looked at it for me. He's a buddy of mine. It's had the battery box redone before. Just making sure there wasn't anyone new in here that might be able to help. Lol. Just wishing I didn't have a brick, really. 😭