Rifle Scopes USO EREK knob

L

Longshot38

Gunny Sergeant
Full Member
Minuteman
Mar 1, 2009
1,121
1
43
Montgomery, TX
#1
I've been considering a purchasing a US optics SN-3 5-25 TPAL w/ the EREK knob. From what I have read on the EREK knob it allows for a maximum of about 80 moa of internal adjustment. With this being the case is there a need to pay the extra for the 35mm tube and will the larger diameter tube allow for more then the advertised internal adjustment?

My train of thought says I'll need the larger diameter tube to get all 80 moa out of such a high magnification scope. However with my limited experience with USO I really have no basis for this. Anybody got any thought on this?
 
#2
Re: USO EREK knob

What's the scope going on? I've never had a problem with not having enough elevation in mine, even on my slow moving .308. Had to do over again, I'd probably go with a bigger tube though, just b/c it's not that much more, and it's not, like you can have too much.
 
#5
Re: USO EREK knob

I would not just look at buying the largest tube possible unless there is good reason for it.

Depending on whose rings you choose and how far forward, how close to the EREK the rear ring is mounted, the ring can start to obscure viewing of the knob markings and revolution marks on the turret housing. The larger the tube, the more pronounced this issue can become. I love how low the EREK is, but it's height can have a cost in the wrong situation.

Call USO and ask them to clarify.....they are very helpful people! Base your decision on what they say and what you need. I have a 3.2-17 with 30mm tube mounted on a 20MOA base on a 308 and have way more elevation than I need to zero at 100 and easily dial for 1000 yard adjustments.

I am not bashing, just an observation. USO is my first choice in scopes for a great many reasons that are heard over and over. These include durability, highly customizable features, exceptional customer service. I have not found a negative in the two USO's I currently own. I have no doubt it will be three, one of these days.
laugh.gif
 
#6
Re: USO EREK knob

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Longshot38</div><div class="ubbcode-body">Right now I'm scope shopping for my ELR platform. It is a 338 Lapua that I will be using to ring steel beyond a mile.</div></div>

A 30mm should work but I would recommend going with a 35mm.
 
#8
Re: USO EREK knob

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: JRose</div><div class="ubbcode-body">Zeroed on a 20 moa rail @ 100y, I have a little over 12 mils before I'm out of travel on my SN-3, 30mm tube. </div></div>

Good intel JRose. That is really helpful. I've got a 40 moa base and am looking at a 600 yard zero. That should give me enough reticle to hold-under below 600.
 
#10
Re: USO EREK knob

I just went and checked my ST-10. I have 15 MOA down and 115 MOA up with a 1/2 MOA EREK. Thats a 30mm tube too. Can't imagine needing much more than that for a fixed 10x to 1k.
 
#11
Re: USO EREK knob

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Rafael</div><div class="ubbcode-body">
Call USO and ask them to clarify.....they are very helpful people! Base your decision on what they say and what you need. </div></div>

While there is a wealth of knowledge here on the 'hide, its all anectdotal-the best bet is what Raf suggested. There are real people at USO, and they actually know what they are talking about (I only suggest you call and bother them because the scope I was waiting on shipped today-I would have never suggested anything that may delay it one moment prior to finding that out
grin.gif
)

As well Raf is correct about the ring/marking issue. If the ring is close the best bet is to scribe, engrave, or some other way mark the top of the ring for an index. I painted a line on my 35mm tubed Erek.
 
#12
Re: USO EREK knob

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: sobrbiker883</div><div class="ubbcode-body">
Rafael said:
(I only suggest you call and bother them because the scope I was waiting on shipped today) </div></div>

You too!?!? I finally got the happy email today as well!!!
Click to expand...
 
#14
Re: USO EREK knob

Yup, Jeff shot me the tracking about 4pm Cali time.

I'm jealous, my 35mm only has about the same travel your 30mm does.....oh wait, that's because minr's <span style="font-style: italic">uber-especiale </span>and that was the SOCOM spec!
 
#16
Re: USO EREK knob

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: sobrbiker883</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Rafael</div><div class="ubbcode-body">
Call USO and ask them to clarify.....they are very helpful people! Base your decision on what they say and what you need. </div></div>

While there is a wealth of knowledge here on the 'hide, its all anectdotal-the best bet is what Raf suggested. There are real people at USO, and they actually know what they are talking about (I only suggest you call and bother them because the scope I was waiting on shipped today-I would have never suggested anything that may delay it one moment prior to finding that out
grin.gif
)

As well Raf is correct about the ring/marking issue. If the ring is close the best bet is to scribe, engrave, or some other way mark the top of the ring for an index. I painted a line on my 35mm tubed Erek. </div></div>

I am with you, sobr;

I hate to bother them and only call when I have to, but for someone wanting a new build a phone call can clear up alot of confusion quickly.

On the knob/turret mark viewing issue......
The USO boys would probably cringe at one idea a user came up with.
We clamped the USO ring-top in my mill and cut a reference mark in the ring, jut a small fore-aft slot with a small end-mill, very shallow. Works pretty well. JBW will probably kick my ass the next time he see's me.
laugh.gif
 
#17
Re: USO EREK knob

I was down at their shop the other day and noticed some funny lines on a customer scopes. Instead of small dots or short lines on the scope body for the click referance, they etched long lines that extended back towards the shooter basically back to the power ring. Thats not something I need but thought it was interesting, and was simply done at the owners request. They will etch lines on the scope or rings anywhere you like.

I have a 3.2-17 in a 30 mm tube with 20 mils of up from a 100 yd zero. It would have more but when you setup an EREK as a zero stop, you sacrafice some travel.
 
#18
Re: USO EREK knob

I didn't realize they would mark the tube, but I am not surprised they are open to almost anything.

I believe you are wrong about losing adjustment via the EREK.
Setting it to stop on your zero leaves you with the MOST elevation adjustment left over........which drops by the amount of adjustment slack you leave below your true zero.
 
#19
Re: USO EREK knob

Please don't call USO. It keeps them from finishing my scope!! LOL. All kidding aside, they are very helpful and a phone call to them would clear up any questions you have. They really are professionals. I'm just an amateur using a pros stuff...
 
#20
Re: USO EREK knob

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Rafael</div><div class="ubbcode-body">I didn't realize they would mark the tube, but I am not surprised they are open to almost anything.

I believe you are wrong about losing adjustment via the EREK.
Setting it to stop on your zero leaves you with the MOST elevation adjustment left over........which drops by the amount of adjustment slack you leave below your true zero. </div></div>

I knew you'd be the one to question that Rafael. I was thinking I have played with lots of their scope internals and right at this moment, i can't remember why it is so. I specifically remember talking to Arnold and him asking me over and over if i could sacrafice the elevation. I'll ask him and tell you what he says.
 
#21
Re: USO EREK knob

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Cpl Snafu</div><div class="ubbcode-body">I was down at their shop the other day and noticed some funny lines on a customer scopes. Instead of small dots or short lines on the scope body for the click referance, they etched long lines that extended back towards the shooter basically back to the power ring. Thats not something I need but thought it was interesting, and was simply done at the owners request. They will etch lines on the scope or rings anywhere you like.
</div></div>

May have been my scope you were looking at-ST10 ERGO with #3 turrets, index line and the windage knob on the "wrong" side?
I got FedEx info from Jeff prior to it being picked up late Wed afternoon, and it was on my doorstep yesterday!!!

The index line is something I really think they should do on all Erek's, esp the big tubed ones. If my prototype 5-25 sticks around it will be getting an index line. The line was a spec for the USO Canadian scopes and I think its a great addition.

 
#22
Re: USO EREK knob

Thats funny, it was on the shipping table, and it was Wed about noon. I promise I didn't get anything on it when I was humping it.

Seriously though, it was a simple no nonsense scope that stood out amongst all the wild stuff they have laying around there. I mean that as a compliment, i'll be ordering the 1.8-10 version shortly, but my windage will be on the right side, I mean the left side.
laugh.gif
 
#24
Re: USO EREK knob

I ran across this old thread searching for info, it is from 2007 so the facts may have changed, but is interesting:

http://www.thehighroad.org/showthread.php?t=174770

"Another note regarding the new erector - I had a direct conversation with Wendell at USO re: the new erector and reticle travel in the different diameter body tubes. He very clearly told me that you can use all the travel with a 30mm tube, that you did not gain any more travel with the larger tubes. He said the "hinge" is currently the limiting factor, not the erector, and until they change the hinge design this will hold true. If you inquire on this subject to others at USO, particularly in forums, you will get a much more vague response than I just posted here."
 
#25
Re: USO EREK knob

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Cpl Snafu</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Rafael</div><div class="ubbcode-body">I didn't realize they would mark the tube, but I am not surprised they are open to almost anything.

I believe you are wrong about losing adjustment via the EREK.
Setting it to stop on your zero leaves you with the MOST elevation adjustment left over........which drops by the amount of adjustment slack you leave below your true zero. </div></div>

I knew you'd be the one to question that Rafael. I was thinking I have played with lots of their scope internals and right at this moment, i can't remember why it is so. I specifically remember talking to Arnold and him asking me over and over if i could sacrafice the elevation. I'll ask him and tell you what he says. </div></div>
Yeah, I gotta cause trouble that way...I am a pain in the ass.
laugh.gif


Choosing the EREK over traditional knobs may reduce overall travel. I am not real sure if the EREK has as much travel as the regular knobs. But...I am pretty sure I am right about the zero-stop regaining all of the "potential" use of the EREK, and that this was one goal of the design.

The EREK has a finite amount of adjustment to it...regardless of the position of the erector and center screw. If you don't zero it near the bottom of the EREK travel, then you will loose elevation adjustment. If you do zero it at the stop, you regain all of the EREK movement....up to the limit of the erector travel.

I am pretty sure about this....but it would not be the first time I was wrong about something.
laugh.gif


 
#27
Re: USO EREK knob

I think I picked up that bastardization here at the Hide.
laugh.gif

Some of the members here are quite brilliant with words, and some are damn near illiterate.
I hope I am near the middle of the pack, or better.
Correction noted and appreciated! I never completed the 9th grade, but I should know better.

Thanks, man!
 
#28
Re: USO EREK knob

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Rafael</div><div class="ubbcode-body">I think I picked up that bastardization here at the Hide.
laugh.gif

Correction noted and appreciated! I never completed the 9th grade, but I should know better.

Thanks, man! </div></div>

You never completed the 9th grade? In these parts we call that over educated.....regardless.

Bob
 
#31
Re: USO EREK knob

Alright guys just to clear up some confusion. I got an email back from Jeff the other day. What he told me is I would gain about 9 moa going from 30mm tube to a 35mm tube. Giving that particular optic around 69 moa of total travel. However Jeff also said it was possible to get around 90 moa out of the SN3 3.8-22. So it is a possibility however I was really wanting the TPAL option.
 
#32
Re: USO EREK knob

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Rafael</div><div class="ubbcode-body">I didn't realize they would mark the tube, but I am not surprised they are open to almost anything.</div></div>

Yup they sure will:
WINDAGE.jpg
 
#33
Re: USO EREK knob

I was just going to ask if someone could post a pic of the reference line because I just couldn't picture what it would look like. Thanks much brand692! My new USO is 35mm tube with EREK and I think a reference would be needed...

Sorry for thread-jacking, but could anyone who currently has a 35mm/EREK/reference line setup post a pic that show a view from just up and behind the scope, basically illustrating how the reference line "helps"? Thanks.
 
#34
Re: USO EREK knob

Pete, if its not done yet, I'm sure USO can burn a line on it no problem.
I added it because my last ST10 just had a very faint line on the turret itself. My new one I just got has a very bold index line, and numbered revolution indications.

I'll try to get a pic here shortly.
 
#35
Re: USO EREK knob

thanks sobrbiker, yeah my scope is not done yet so I'm trying to gather all info from others' experiences to see if anything else needs to be done prior to completion. It seems every day I check on SH I discover a new item of concern from experienced shooters using USO scopes, and then a customized solution provided by USO that is either already available or USO has no problem doing it... That's why I love this site and USO so much.
laugh.gif


I'm hoping my build is "delayed" (I know, someone wants their scope built late for a change) just enough to see the release of the 11 mil/rev. EREK knob instead of the current 9 mil/rev. EREK
smile.gif
 
#36
Re: USO EREK knob

Just spoke to USO, they confirmed that the EREK knob does NOT limit elevation but instead allows you to maximize the available elevation once the center screw has been adjusted.

I think the 11MIL rev. knob is already available. Unless I'm mistaken, when I was there on Thursday last week, they said if I ordered on now it would have it - likewise with their EREK Milestone (MTC) knob which felt very solid indeed.
 
#37
Re: USO EREK knob

My convo with Jeff last week about the 11mil EREK is that it will be available somewhere around 8 weeks from now (maybe), and that if the knob is available before my scope is done it will be put on my scope. Right now I've only seen this EREK on the one-off prototype USO scope that Sobrbiker has.

I've heard little about their Milestone EREK, what is different about that EREK?
 
#38
Re: USO EREK knob

Milestone is good for 1 1/4 revolutions or about 15 mils total. The Milestone has the "More Tactile Clicks" every 10 clicks or full mil-radian.

This whole thread overlooks some very basic concepts of the EREK and USO's scopes.

One, the erector can be moved separately from the outer knob. Two, the EREK has been in now a total of 4 configurations counting the Milestone - 1 turn 9 mil, 2 turn 9 mil, 3 turn 9 mil, and now 1 1/4 turn 11 mil. The erector travel exceeds that of all variants of the knob, at least the current design of the USO erector.

As far as additional erector travel, not to be confused with KNOB travel, is concerned, I have not been able to get a solid answer as to the difference in travel amount for their current erector design when installed in a 30mm versus a 35mm tube. Given the amount of travel available in the 30mm tube, in excess of 90 MOA or 26 mils, what difference does it make?
 
#39
Re: USO EREK knob

9H;
Damn but you have a great deal of knowledge on the EREK, especially the new configurations! Have you another scope on order? That's right....you attended SHOT. Sorry I missed it.

In my defense; I did use the fact that the EREK knob moves independently....thus giving you the most "up" travel left over if you actually make your zero near the bottom. Accomplishing this REQUIRES use of the center screw.
IMO, that is the single greatest benefit the knob brings.
 
#40
Re: USO EREK knob

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Rafael</div><div class="ubbcode-body">9H;
I did use the fact that the EREK knob moves independently....thus giving you the most "up" travel left over if you actually make your zero near the bottom. Accomplishing this REQUIRES use of the center screw.
IMO, that is the single greatest benefit the knob brings.
</div></div>

What other benefits are there? I thought this was THE whole intent of the knob. If there are others, then great!
 
#42
Re: USO EREK knob

That, and the clicks are rock solid, more so than my NF for sure or any Leupold I've owned.

Its lower, its wider, and I think its the easiest to operate with gloves.
 
#43
Re: USO EREK knob

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: JRose</div><div class="ubbcode-body">For me, 9 mils in one rev without the clicks being so close together it sounds like a zipper when you turn it. </div></div>

same for me......
 
#44
Re: USO EREK knob

Other features I appreciate:

The fact that I can use it as a zero stop, and I do.
The low profile of the knob.
As JRose and others pointed out.....The large diameter makes for good labeling and clicks even though you get alot of adjustment per-rev.
The fact that you can have custom marked knobs made.

I am probably forgetting something in that list.
 
#45
Re: USO EREK knob

Hey Bob, I'm not trying to be too harsh on you and the likes so forgive me please if I came across that way. My mind is the type that likes to go back to basics, put the pieces together, and draw a conclusion on which direction to go.

I purposely left two things out of the previous post. One just has to take a look at USO's broader product line, not just the scopes, to better understand the system approach they have taken and why. Windage adjustable rings - how many other vendors provide them? Also, different base slopes. Yes, other vendors do provide those.

Combine all three- (formerly) limited knob movement in the 2 turn EREK, a base matched to a specific distance range you plan to shoot, and windage adjustable rings, and you get a system that allows you to tune the rifle to work within a broad but specific distance range. The other thing I left out was windage travel. Even though the erector has a bunch of erector travel, if the base slope, rifle zero, and static (via rings) windage adjustment are not matched up, then you won't have much windage travel at the place you need it most - long distance.

Until someone perfects square scopes with square lenses, total elevation travel, while an important element, is not the only element that needs to be considered when evaluating a WS's optic and mountings.

I know some of what I posted here pertains to other threads currently active here on base slope, so my responses are in context of those as well.

One scope I really like but do not own as I have not found enough of them to put on all the rifles is the S&B 3-12 PM-I. The PM-I knob has a zero stop and one revolution to go 14 mils along with enough erector travel to deal with a variety of zeros, base angles, and round trajectory combinations.

What would I like to see in the EREK? 10 mils/100 click per rev, two turns, MTC for the whole 2 revs, and LARGE numbers. I'm going to large number 9 mil knobs now. They will be manageable to keep track of where you are once you go past a full turn up, but the 10 mil would be a bit easier.

I feel for the makers like USO; if you've been involved with the .mil machine and SOCOM for any length of time you know that they publish specs that sometimes make sense and sometimes don't, change them often, and rarely buy in quantity what they asked for. The scope Steve has is a perfect example of how USO busted their butt at considerable expense to meet and exceed the PSR scope requirements, and for that will receive no revenue any time soon. The 11 mil EREK was a part of that. I'd sure like to have seen them be able to direct that development $$ towards a 10 mil EREK, and no I didn't come to that conclusion because NF released a 10 mil/turn knob at SHOT. It just so happens to make a lot of sense. Will that stop me from buying more USOs? Absolutely not.

Love the EREK and so do most people that shoot mine, a correctly adjusted one, for the first time.
 
#47
Re: USO EREK knob

You were not harsh, Leo. Speak your mind.....I appreciate it.
I have been meaning to call you to hear more of what you discovered at SHOT. I regret that I could not catch up with you there. It would have been good to pick your brain over a few beers.

Lets see here.....

When it comes to the detent ring I am in a worse boat than you since my SN-3 has 1/4 IPHY elevation adjustments......so the 90 click detent leaves me with 22.5 IPHY per rev......at least you have a whole number to add on the second revolution.
laugh.gif
I would be happier with a 100 detent ring as well, would only need to add 25 for my second rev.

Like you, I would guess that the return on investment with a new detent ring has alot more potential on a contract scope than on just another option for the average Joe buying a USO. I have no doubt I would come to the same conclusion were I making the decision.

What is MTC? That is a new one for me.

I am bullish on USO scopes because I am very happy with the ones I purchased, as well as the support the company offers. I do agree that one should mate the scope with a base that squeezes out as much performance as possible.

I am not sold on the need for windage adjustable rings. If you do use the adjustment, you cannot remove and replace the scope via the rings without re-zeroing windage....unless this has been changed.
Honestly, if I am willing to spend this much on a scope, and I am, I would not leave it on a rifle that had such serious windage alignment problems. Either the base is screwed, or the action is whacky, or the barrel is....or someone screwed them up installing them. Also, I don't shoot anything that requires anywhere near the full travel of these scopes. If it were more than a 5 or 10 minutes off-center in windage I would look for and correct the problem with the action/base/rings/barrel/installation. Just my opinion, but then I can correct the problem at my home shop so I may not be the average user. Would you correct a 20MOA windage alignent issue with rings? Alot of those buying USO's put them on custom rifles.....do they just accept a large windage deviation?
 
#48
Re: USO EREK knob

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Rafael</div><div class="ubbcode-body">I am bullish on USO scopes because I am very happy with the ones I purchased, as well as the support the company offers. I do agree that one should mate the scope with a base that squeezes out as much performance as possible.

I am not sold on the need for windage adjustable rings. If you do use the adjustment, you cannot remove and replace the scope via the rings without re-zeroing windage....unless this has been changed.
</div></div>

My sentiments exactly.

The only gripe I really have with USO is the odd number of clicks per rev on their turrets. One of the reasons I chose to go mil/mil was taking a hard look at the moa (1/4 and not a bad, 1/2) erek dials.
 
#49
Re: USO EREK knob

That's why sf340driver's idea of 1/3 MOA or IPHY adjustments is so attractive. With the current 90-detent ring we would get 30 MOA/IPHY per rev. That would be pretty nice, and still be fairly fine.

If I had it to do over again, I would likely order 1/2 IPHY adjustments for that reason.
 
#50
Re: USO EREK knob

Actually you can take the scope off and put it back on without losing zero with the windage adjustable rings. Use blue loc tite on the right side screws and nail polish on the left side screws. If you have a need to use the rings to zero the windage, do so. When taking the scope off, just loosen the left side screws as you would with badgers. The right side ones will stay put. Another option is to just run one side in all the way, again with blue loc tite on the screws, and only loosen from one side.

MTC = More Tactile Clicks = Milestone option. Right now the Milestone is only offered in the 11 mil per rev variant of the EREK if my notes are correct from my talk with Jeff.

Agreed on large windage adjustments - problem lies elsewhere. I'm not saying they are great or saying they are bad - they are part of the system USO developed, so try to understand them for what they are is all I'm getting at.
 
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