Rifle Scopes Viper PST FFP - w/20MOA base, only 9 MIL left?

jtb33

jtb33

Full Member
Full Member
Minuteman
Jun 15, 2010
509
27
PHX, AZ - USA
#1
So I finally got my Vortex Viper PST 6-24x50 FFP MRAD on Friday (after over a year wait). Anyway, there are enough reviews on them, and mine looked great, so I proceeded to mount it on my Remington 700. It sports a Badger Ord 20MOA base and Badger Ord medium rings. Got it mounted per spec's, boresighted it and took it to the range to sight it in. Fired two shots @ 100Y, which showed that it was shooting about 3MIL low and 1MIL right. Made my adjustments and it was spot on after two shots to confirm it. Also checked my POI shift with my suppressor to record that.

I shot it a bit more and was really impressed with it. I put about 50 rounds downrange with it. So when I got home, I figured that I'd set the "CRS" Zero Stop it in. I read the manual, watched the video and put in the shims per the instructions. It needed all but two of the shims. So that's good, but now, I only have about 9MIL's elevation left from a 100 yard zero, which is only good enough to get me to around 825Y with my 168gr AMAX load - definitely an issue here. I see that the Viper PST's are supposed to have 19MIL of total travel. Did I get a bum scope, or does setting the Zero stop reduce the elevation I have left? If it matters, I am not able to get the turret back down to the "0" revolution mark when putting the turret back on after shimming it. My "Zero" is at the "1" rotation mark - if that makes sense.
 
#2
Re: Viper PST FFP - w/20MOA base, only 9 MIL left?

There seems to be something else going on here. I used mine to shoot 1000 yards with a 20MOA base no problem. Did you go through the full range to see how much elevation adjustment you actually have? Mine is precisely 19mils. I switched to the Badger 30 minute base, and I have 2.5mils to the bottom, with exactly 16.5 mils up. So, with my rifle, I had about 13.5 mils up before the switch. Then again, you could have got a lemon
smirk.gif
you never know, but you definitely need to check the full range of adjustments to make sure.
 
#3
Re: Viper PST FFP - w/20MOA base, only 9 MIL left?

Take one shim out, it's really hard to get it to stop exactly on the Zero like a NightForce where it stops solid. Mine goes a bit below but then you just turn it back to Zero. Sometimes it's nice to have it be able to go a bit lower just in case.

As far as you not having much verticle travel up left, no idea but am surprised you needed that many shims. I probably didn't use even half to set my 200 yard zero on my 260 XP but I did go with the 4-16 since it had 10moa more travel then the 6-24.

Topstrap
 
#4
Re: Viper PST FFP - w/20MOA base, only 9 MIL left?

I removed the shims and verified that it has just under 20MIL's of travel, total. However, from it's current 100Y zero, even without the shims, it still only has just over 9MIL of elevation remaining.

I wonder if there is something off in the erector, or... hmmm...

NOTE: I did verify that the rings are the same size (matching numbers on them). I did buy the rail second-hand. It was advertised as a 20MOA rail, and the part number on it corresponds to the 20MOA rail: 1005-306-06. Rail and rings are installed correctly.

Anything else I could be missing before I contact Vortex?
 
#5
Re: Viper PST FFP - w/20MOA base, only 9 MIL left?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: jtb33</div><div class="ubbcode-body">I removed the shims and verified that it has just under 20MIL's of travel, total. However, from it's current 100Y zero, even without the shims, it still only has just over 9MIL of elevation remaining.

I wonder if there is something off in the erector, or... hmmm...

NOTE: I did verify that the rings are the same size (matching numbers on them). I did buy the rail second-hand. It was advertised as a 20MOA rail, and the part number on it corresponds to the 20MOA rail: 1005-306-06. Rail and rings are installed correctly.

Anything else I could be missing before I contact Vortex? </div></div>

I would just give Vortex a call you sound as if you've got your ducks in a row, and they are generally very knowledgable and helpful with things like this. Let us know how it turns out!
 
#6
Re: Viper PST FFP - w/20MOA base, only 9 MIL left?

I would contact them regardless, they can also throw out some ideas that might be causing problems. They may also know the exact solution. You may have a lemon, but I can assure you that they will insure you don't have a sour taste in your mouth after dealing with them. They will set you straight, and when you get a good one, you will really like it for the price it is. I'm not in any way envious over shooters with higher priced scopes because mine tracks perfect, has pretty damn nice glass, and the clicks are great. Also, the thousands that aren't tied up in my one scope have bought me a new barrel, a new stock, and other upgrades.
 
#7
Re: Viper PST FFP - w/20MOA base, only 9 MIL left?

Thanks for the comments and suggestions. I mostly wanted to make sure it wasn't something dumb that I was just overlooking before I bothered Vortex support. I'll give them a call tomorrow morning and report back.
 
#8
Re: Viper PST FFP - w/20MOA base, only 9 MIL left?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: jtb33</div><div class="ubbcode-body">Thanks for the comments and suggestions. I mostly wanted to make sure it wasn't something dumb that I was just overlooking before I bothered Vortex support. I'll give them a call tomorrow morning and report back. </div></div>

I wouldn't have done anything differently or come to a different conclusion, not that that's saying much
laugh.gif
 
#9
Re: Viper PST FFP - w/20MOA base, only 9 MIL left?

This might sound stupid and I don't mean to insult your intelligence, but do you have the base installed backwards? I think this would be hard to do on a 700 because IIRC the hole spacing is different.

Also just check to make sure that you're going the correct direction with the elevation.

I just mounted the scope (also after waiting over a year) and using a 20 MOA base, it is set at about 8 - 9 mil from the BOTTOM.
 
#10
Re: Viper PST FFP - w/20MOA base, only 9 MIL left?

Is there a big gap between your barrel and the objective bell? If there is, try using a set of standard rings .823" instead of the medium rings 1". I had a set of standards on my FN with a NF 3.5-15 and there was at least 1/4" gap between my barrel and the scope objective. Hope this helps.
 
#11
Re: Viper PST FFP - w/20MOA base, only 9 MIL left?

Definitely not backwards (is that even possible?). Not a ton of space between the barrel and objective bell. I could probably get away with the low Badger Ord rings, but there isn't enough gap to concern me, really.

Here, this may help:

IMG_2350-1280.jpg
 
#13
Re: Viper PST FFP - w/20MOA base, only 9 MIL left?

What surprises me is that you were shooting low at 100 from near mechanical zero when you have a 20MOA base installed.

It seems as though it is not a scope issues as you have determined it is very close, if not excatly what the specs say.

My thoughts, and I may be wrong:
You didn't bed the base.

If you were to remove the scope and remove the rear screws on the base, I believe you will find a significant gap between the bottom of the base and the top of the reciever (if the base has not taken a set). Another way to check for this is to put a level on top of your base (while it is mounted) and see if it "rocks" back and forth.

Once you have properly bedded the base, you will gain all of the benefit from the angled base and also relieve a lot of stress on the scope tube.

Good luck and report back.
That is a fine looking stick there.
 
#14
Re: Viper PST FFP - w/20MOA base, only 9 MIL left?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: fdkay</div><div class="ubbcode-body">What surprises me is that you were shooting low at 100 from near mechanical zero when you have a 20MOA base installed.

It seems as though it is not a scope issues as you have determined it is very close, if not excatly what the specs say.

My thoughts, and I may be wrong:
You didn't bed the base.

If you were to remove the scope and remove the rear screws on the base, I believe you will find a significant gap between the bottom of the base and the top of the reciever (if the base has not taken a set). Another way to check for this is to put a level on top of your base and see if it "rocks" back and forth.

Once you have properly bedded the base, you will gain all of the benefit from the angled base and also relieve a lot of stress on the scope tube.

Good luck and report back.
That is a fine looking stick there. </div></div>

This is pretty good advice on a stock Rem 700 the base definitely should be bedded, and in an extreme case I guess it could throw your base off a good deal.
 
#15
Re: Viper PST FFP - w/20MOA base, only 9 MIL left?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: fdkay</div><div class="ubbcode-body">What surprises me is that you were shooting low at 100 from near mechanical zero when you have a 20MOA base installed.

It seems as though it is not a scope issues as you have determined it is very close, if not excatly what the specs say.

My thoughts, and I may be wrong:
You didn't bed the base.

If you were to remove the scope and remove the rear screws on the base, I believe you will find a significant gap between the bottom of the base and the top of the reciever (if the base has not taken a set). Another way to check for this is to put a level on top of your base (while it is mounted) and see if it "rocks" back and forth.

Once you have properly bedded the base, you will gain all of the benefit from the angled base and also relieve a lot of stress on the scope tube.

Good luck and report back.
That is a fine looking stick there. </div></div>

Thanks for the additional info. I spoke to Vortex and gave them the same info I posted here. They just said to send it in and they'd look at it. It's even shipping on their dime - that's great service.

However, before I send it in, when I get home tonight, I will check the base using the level method you mention and see if the base is a bit concave so that the level "rocks". Perhaps I'll also take out the SS 10x42 that I just bought for my Barrett and mount it on this rifle and see if it exhibits the same issues. Anyone know the full range of travel on the SS 10x42 (non-HD)?
 
#16
Re: Viper PST FFP - w/20MOA base, only 9 MIL left?

Like fdkay said it is odd that you were shooting that low out of the gate. As the scopes go out mechanically centered. I think what a lot of people for get about is that bases on Remington actions need to be <span style="text-decoration: underline">properly</span> bedded. If not the gun will almost always shoot low and to the right. This is caused by the way that Remington finishes/polishes their actions before they coat(blue/parkerize,etc..) them. Also on top of all this you still have to take into consideration of how straight the barrel bore was drilled and which direction it may or may not be throwing the bullets.

I will be more than happy to look at your scope when it arrives, but I am 99.9% sure that the action/base is most likely the culprit.


Feel free to contact me anytime.




Scott
 
#17
Re: Viper PST FFP - w/20MOA base, only 9 MIL left?

Thanks, Scott. Before I bother you with sending it back, I'll check the base and verify that it's set up correctly and also test it with the above mentioned scope. If it is indeed the base, then the other scope should exhibit the same issue.
 
#18
Re: Viper PST FFP - w/20MOA base, only 9 MIL left?

So I removed the Badger rings and used a carpenter's square (and level) to check the base and it is absolutely true and perfectly flat/even. Additionally, the base appears to be bedded using epoxy.

So took my SS 10x42 out of my M99 and checked the total elevation travel on it: 127MOA. I then put my SS 10x42 scope at mechanical zero. I put the rings back on the base and then put the Viper PST in the rings and set up my Leupold magnetic boresighter to verify the zero point on it (it's still set to my rifle's 100Y zero), left the boresighter on the muzzle and then swapped the scope for the SS 10x42. The elevation at mechanical zero on the SS in the rings was within 1MOA (one) of the zero on the Viper PST, as it was zeroed in @ 100Y.

I will be sending it back to Vortex tomorrow.
 
#20
Re: Viper PST FFP - w/20MOA base, only 9 MIL left?

Okay, noob question. I have a EGW HD 20moa base coming (part# 80002). I will be installing it on my Remington 700 short action, and have never heard of this bedding thing for the base.... Will someone please elaborate?
 
#22
Re: Viper PST FFP - w/20MOA base, only 9 MIL left?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: clj94104</div><div class="ubbcode-body">Okay, noob question. I have a EGW HD 20moa base coming (part# 80002). I will be installing it on my Remington 700 short action, and have never heard of this bedding thing for the base.... Will someone please elaborate? </div></div>

Here ya go:

http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=2402990
 
#24
Re: Viper PST FFP - w/20MOA base, only 9 MIL left?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: CSTACTICAL</div><div class="ubbcode-body">I tend to recommend 30moa bases for scopes that are 20x and above. The more magnification you have the less MOA in the scope.

Mike @ CST </div></div>

That is not really a good idea Mike. If the scope has only 40 to 50 MOA (anything less than 60) of total travel you will probably not be able to get a 100 yard zero with a 30 MOA base.

I just bought a Valdada 36x benchrest scope from you and received it yesterday (THANKS!)

It has an advertised 40 MOA total travel (45 actual) and I have about 1.5 MOA of DOWN left after mounting with a 20 MOA base. A 30 MOA base would have totally screwed me for a 100 yard zero.
 
#25
Re: Viper PST FFP - w/20MOA base, only 9 MIL left?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: jtb33</div><div class="ubbcode-body">

So took my SS 10x42 out of my M99 and checked the total elevation travel on it: 127MOA. I then put my SS 10x42 scope at mechanical zero. I put the rings back on the base and then put the Viper PST in the rings and set up my Leupold magnetic boresighter to verify the zero point on it (it's still set to my rifle's 100Y zero), left the boresighter on the muzzle and then swapped the scope for the SS 10x42. The elevation at mechanical zero on the SS in the rings was within 1MOA (one) of the zero on the Viper PST, as it was zeroed in @ 100Y.

</div></div>

jtb,

I spoke with you on the phone about this problem. If I'm correctly understanding that you set the SS to the middle of it's travel range, the statement above seems to perhaps indicate that you actually have a flat base, not 20 moa. You are observing that both of these scopes are very close to their mechanical centers when rifle is zero'd at 100 yards. If the base is indeed 20 moa, the SS should not be near mechanical center at the 100 yard zero.

Paul @ Vortex
 
#26
Re: Viper PST FFP - w/20MOA base, only 9 MIL left?

+1 to Paul.

9 mils remaining on the PST is almost mechanical zero (.5 mil off). You may not actually have a 0moa base, but one way or another it sounds like your rifle shoots high.
 
#27
Re: Viper PST FFP - w/20MOA base, only 9 MIL left?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: VTXPaul</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: jtb33</div><div class="ubbcode-body">

So took my SS 10x42 out of my M99 and checked the total elevation travel on it: 127MOA. I then put my SS 10x42 scope at mechanical zero. I put the rings back on the base and then put the Viper PST in the rings and set up my Leupold magnetic boresighter to verify the zero point on it (it's still set to my rifle's 100Y zero), left the boresighter on the muzzle and then swapped the scope for the SS 10x42. The elevation at mechanical zero on the SS in the rings was within 1MOA (one) of the zero on the Viper PST, as it was zeroed in @ 100Y.

</div></div>

jtb,

I spoke with you on the phone about this problem. If I'm correctly understanding that you set the SS to the middle of it's travel range, the statement above seems to perhaps indicate that you actually have a flat base, not 20 moa. You are observing that both of these scopes are very close to their mechanical centers when rifle is zero'd at 100 yards. If the base is indeed 20 moa, the SS should not be near mechanical center at the 100 yard zero.

Paul @ Vortex </div></div>

Yes, I spoke to you, I believe. The SS's mechanical zero was within 1MOA of the 100Y zero of the Viper PST. The scope was sent out, so we'll see what you guys find, but unless this Badger Org base is incorrectly stamped, the part number stamped onto it indicates as much, and it's apparent forward cant is easy to discern from looking at it. It isn't shimmed in the front, either.

If there is something else I can check or take pictures of, I'd be more than happy to do so.

If you guys get the scope and say that it's all normal, well, we'll go from there.

I have a NF 3.5-15x50 that I can take out of another rifle and see what that one does... I'd prefer not to, but if you guys get the Viper PST and say it's all working correctly, obviously at that point it must be *something* on my rifle, base or rings...
 
#28
Re: Viper PST FFP - w/20MOA base, only 9 MIL left?

We'll let you know quickly ! Certainly sounds like you've got canted rail, but it's a bit of a mystery with both scopes near mechanical center at 100 yards. There are other possibilities such as barrel/receiver alignment and bore/barrel alignment which could cause this.

Paul
 
#30
Re: Viper PST FFP - w/20MOA base, only 9 MIL left?

Although it is very hard to tell, I do not see any sign of bedding compound on the rear of the base. What type of bedding compound was used?
 
#31
Re: Viper PST FFP - w/20MOA base, only 9 MIL left?

Well, I put my NF 3.5-15x50 on there and used the boresighter to get the POI to be the same as what it was when the Vortex PST was on there. Once "zeroed", I had 17 MLIS of up elevation left on the NXS and 15 MILS of travel downwards left.

So at this point, I doubt it's the base, and I doubt it's the rings. Perhaps it's just how the barrel was installed to the receiver or something. It's a VERY accurate rifle - best I've had - and had it holding .75 MOA 5-shot groups @ 100 yards w/168gr AMAX.

At this point, I'm fully expecting Vortex to say that the scope is perfect. It should arrive there on Monday.
 
#32
Re: Viper PST FFP - w/20MOA base, only 9 MIL left?

Sounds like you need to get yourself a 40moa base now, really nothing you can do about where the rifle wants to shoot.

Just out of curiosity, how mechanically centered is the windage?
 
#34
Re: Viper PST FFP - w/20MOA base, only 9 MIL left?

Just to let everyone know. I received this scope on Monday. The reticle and erector tube could not have been more centered,and the problem is being caused by the gun, which is what everyone was kind of figuring by mid thread including jtb33. So I just thought I would fill everyone in on what the conclusion to this was and what I found after looking at the scope.

Unfortunately this is very common with factory barreled guns and as our sport grows we see it more and more. There are two ways to fix/remedy this issue. One is that you can just get a steeper canted base and the other would be to get your gun re-barreled by a competent gunsmith. If you choose the latter I would highly recommend getting the action trued up also. A competent gun smith would also advise this in most cases.


Feel free to contact me or anyone here at Vortex anytime.


Best Regards
Scott
 
#35
Re: Viper PST FFP - w/20MOA base, only 9 MIL left?

Again, thanks Scott!

Since the gun is very accurate and this issue only seems to involve elevation rather than windage, I just purchased a 1-piece Nightforce 40MOA base. So hopefully this will address it and I can continue to use this PST on that particular rifle. It's definitely a great scope and has the perfect magnification range for that Remington.
 
#36
Re: Viper PST FFP - w/20MOA base, only 9 MIL left?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: jtb33</div><div class="ubbcode-body"> Additionally, the base appears to be bedded using epoxy.
</div></div>


I'd think that'd be the culprit before the barrel, but I don't know anything about anything.

Third Saturdays of the month at PRGC, 7am bring that puppy and 50 or so rounds out and shoot!
 
#38
Re: Viper PST FFP - w/20MOA base, only 9 MIL left?

How many other scope manufacturers will chime in on boards like this and not only give someone advice, but tell them to send the scope in for a checkup. And, after all that post the results from that checkup. Vortex is a great company, thanks for the support Scott!
 
#39
Re: Viper PST FFP - w/20MOA base, only 9 MIL left?

I may be wrong, but something looks wrong with the rings if they are medium. I have the 6-24x50mm PST FFP MOA scope mounted with Burris Extreme Tactical rings on top of a EGW 20 MOA Picatinny rail. The rings are 1/4" thick from the bottom of the scope to the bottom of the ring and only gives me a 3/16" gap between the scope and the barrel. Yours should have more of a space there I would think.(?)
I shoot a 6mm Norma BR. at 1,000 yds. and have quite a bit of up left.

Here are some pictures of mine mounted:

http://forum.gon.com/showthread.php?t=584687&highlight=

40gt
 
#40
Re: Viper PST FFP - w/20MOA base, only 9 MIL left?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 40gt</div><div class="ubbcode-body">I may be wrong, but something looks wrong with the rings if they are medium. I have the 6-24x50mm PST FFP MOA scope mounted with Burris Extreme Tactical rings on top of a EGW 20 MOA Picatinny rail. The rings are 1/4" thick from the bottom of the scope to the bottom of the ring and only gives me a 3/16" gap between the scope and the barrel. Yours should have more of a space there I would think.(?)
I shoot a 6mm Norma BR. at 1,000 yds. and have quite a bit of up left.

Here are some pictures of mine mounted:

http://forum.gon.com/showthread.php?t=584687&highlight=

40gt </div></div>

"Medium" ring sizes across manufacturers are not necessarily the same height and can vary somewhat significantly. Mine uses Badger Ordnance "medium" rings which measure 0.885”.

Likewise with scope bases. EGW bases sit fairly high, comparatively speaking. This one had a 20MOA Badger Ordnance base pictured, which I just changed to a 40MOA Nightforce base.
 
#41
Re: Viper PST FFP - w/20MOA base, only 9 MIL left?

New 6-24 PST on a savage with a TPS 20moa base and tps low rings leaves me 10.4 mils up. Sounds like this is just a normal situation for a factory gun. This savage 5R is freakishly accurate and I love the PST so I'll just deal with it. Reticle is good to get me past 10.4 if needed.
 
#42
Re: Viper PST FFP - w/20MOA base, only 9 MIL left?

I have a savage 10FP in 308 EGW 20MOA base and vortext 6-24x50. I had no trouble dialing up 36 MOA to hit at 1000yds. And had to dial down 4 MOA to be on target. Great scope for the money.I know that you are talking mil, I just wanted to show that I had plenty of elevation. I realy don't know how this compares to mil.
 
#43
Re: Viper PST FFP - w/20MOA base, only 9 MIL left?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: hogrider2003flht</div><div class="ubbcode-body">I have a savage 10FP in 308 EGW 20MOA base and vortext 6-24x50. I had no trouble dialing up 36 MOA to hit at 1000yds. And had to dial down 4 MOA to be on target. Great scope for the money.I know that you are talking mil, I just wanted to show that I had plenty of elevation. I realy don't know how this compares to mil. </div></div>

My estimation of my 10.4 mils would give me 37.44 MOA. Glad yours is working out. It's fine for me as I have plenty of loads that shoot well @ high velocity. Might be an issue for some though.
 
#44
Re: Viper PST FFP - w/20MOA base, only 9 MIL left?

I put a 4th gen IOR 3.5-18 on my 700 VSF using a EGW 20 MOA base. It put me about in the middle of the elevation adjustment range with about 9.5 MILS left up.

I did the math and ordered a 40 MOA base. It turned out to be too much, even though the math said it would work. Ended up going to a 30 MOA Badger base and it put me into about 15+ MILS left ^ with a 100 yard zero. Works fine now.

Point being, sometimes the math just doesn't work out to what what will finally work.

Ended up using the 20 MOA base on another 40XBKS with a Bushnell HDMR and it has plenty of upward travel left since the HDMR has a bit more travel in it than the IOR does.

Hope it works out for you.
 
You must log in or register to reply here.

Similar threads

R
Got my 5-25 Viper HD today.
Replies
6
Views
819
RMS65
R
J
Cheapish scopes
Replies
17
Views
799
jdulaney
J
O
Leupold MK IV LRT 8.5-25 x 50 turret issue.
Replies
11
Views
342
OldieBuddyGoodie
O
W
Rifle Scopes My ad hoc LPVO Comparision: SE, PST Gen II, SMRS II Pro, Vudu
Replies
4
Views
544
wcoats
W
P
Unexplained elevation shift, reason?
Replies
17
Views
586
Rodney65
Rodney65
Top Bottom
Back
Home
Forums
Merch
Alerts