New Scope fore my Benjamin Regal NP

[Redharris]

I have a Benjamin Regal NP in .22 cal.
It is a nice rifle, that is quite accurate. I have even learned to deal with the Crappy stock trigger.
However, the Center Point 4x scope that came with the gun has been a Thorn in my side since day one!
Today. I took the  rifle out to my backyard Range and shot 2 Five shot groups at 20 yards that could be covered by a Nickle.
The next 5 shot group inexplicably dropped 4 vertical inches, but the group was still the same small size.
This is a regular occurrence with this Scope. I readjusted for elevation and tapped the scope a couple times to settle it, then shot 10 pellets to let the scope stabilize.
I then proceeded to shoot some pretty decent groups for about 15 minutes, at which point the rifle started to shoot  about 3 inches High........
Sigh.....I am Done with this scope.....Time for a replacement.

I have this spare scope that my Brother Gave me. The MFG is NikkoStirling. It is an inexpensive 4x32AO scope that is mounted on my Savage .22lr Rifle. I use it to punch paper the the Range, and it works just fine on my Rimfire Rifle. My question to you guys is this..... Will the recoil of the big Nitro Piston rifle Kill this scope? I Know that Springer Rifles are hard on scopes due to the double recoil they have going on , but what about Nitro Piston guns? Here is a LINK http://www.webyshops.com/brand/Nikko-Stirling-Mountmaster-Rifle-Scopes-brand/NIKKO-STIRLING-Mountmaster-4x32-AO-Rifle-Scope-Illum-Mil-Dot-Reticle-w-Rings-NMMI432AO.html to the scope. Anyone have any experience with this Scope?

[Roadworthy]

First of all, why do you think it's the scope?  I had a Nitro Venom pulling that stuff and Crosman had me return it under warranty.  They paid the postage, sent a new gun, and a new scope.  You have quite possibly got a problem with repeatability on your barrel lockup.

If you choose to go the scope route first, check with Nikko Sterling to confirm whether the scope is satisfactory for a springer.

By the way, I got so fed up "knowing" it was the scope I purchased a new scope to solve the problem.  It didn't.

[Redharris]

Your Question is Fair.....Why do I think my problem is the scope?
If I had a barrel lock up problem, I would expect Flyers in various different directions,,,, wouldn't I?
 My groups are consistently small. For the most part, it is the GROUPS that move around, not the individual shots.
Also, the rifle chronographs consistently right around 700fps with Crosman Premier pellets.
That seems to indicate that the Piston is working in a Healthy manner and that the seals are not faulty.

I wish the rifle came equipped with Iron sights. That would allow me to remove the scope and troubleshoot my problem a bit easier.
But alas the shrouded barrel leaves no way to mount iron sights. My best guess is the scope.....

[Topend Yobbo]

The mountmasters are designed for air rifles.
Weather or not an XL will destroy it is only something time will tell.
Good luck trying to sort out the problem.

[Roadworthy]

Regarding barrel lockup, the alive jam locks the barrel into position.  If there is anything preventing a proper lockup you can get a vertical dotted line as a group.  All may be in line horizontally but move vertically.  Other things can permit vertical movement as well, to a greater or lesser degree.

You can even have a sloppy fit of the wedge piece itself in its hole, allowing sticking.

If your pivot has a problem it can cause horizontal and vertical movement.

[Bullit]

The Crosman breakbarrel hinge and bushings, has to be paid more attention to the consistent breech sealing issues, than the fixed barrel rifles...as well as barrel position.  Over adjustment of the scope turrets,vertically or horizontally, will also give you problems for consistency. The erector springs (both of them to keep tite), need good pressure, to hold it (erector tube) in place.   Checked Droop?

[Redharris]

@t Bullit.
I have considered that I may have adjusted the elevation so far as to remove proper tension the erector springs. Not sure how to Definitively KNOW that, or what to do if that is the case. Have HEARD of "droop," but not sure EXACTLY what it means. Is there a practical way for me to Check for droop? If so, how do I go about it.

@ Roadworthy
My barrel seems to lock into position quite firmly. When cocked, there is absolutely no play between Barrel and Breech. All is Tight.  The cocking mechanism/lever looks to be in good condition. There is no interference between the cocking mechanism and the Piston tube or the barrel. The lever itself is straight and there is no excessive wear or looseness that I can see. It looks good to me......

[Redharris]

So, I have been thinking on my problem after considering the comments/advice I've gotten in this thread.
Did some research about Droop and checked my rifle. Cant find any Measurable droop. Took a 3 foot metal straight edge to the rifle and Barrel lines up with breech just fine.
Barrel certainly does not LOOK bent, but as my rifle has a fully shrouded barrel,,,,,who KNOWS what is going on Inside the shroud. Seems OK though.

Read some threads about Scope Mounting and Adjustment. Decided to tackle my problem from this angle and see what happens.
Step 1.) Mechanically centered my elevation and windage adjustments on the scope, then went out and shot a group at about 25 yards. This is what I got, (see picture).


As you can see, the gun is shooting about 5 inches high,,...and windage is pretty decent.
Step 2.) I removed the scope and shimmed the front mount. I used a paper Business card and trimmed to fit the scope mount. Tightened everything down and went out to shoot another group. This is what I got, (see picture).


Not bad at all. There are 7 pellets in that group, shot from about 25 yards using a sandbag rest. I STILL have not touched the elevation or windage adjust screws, since the original centering was done at the beginning of this post. Just got lucky, with the initial centering adjustment, I guess. Now I will have to see, over the next few days, if the rifle Holds this zero adjustment......In the Past, it has not done so. But, NOW the scope is mechanically centered and there SHOULD be good EVEN spring tension on the crosshairs.

[JR]

Looks like it is doing ok now, the scope might be the problem but I would also look at the rings. This power plant has a good amount of shock of these rings.

My now Trail started out life as a Regal and it shoots really well. I never used the original scope until several months later, but my scope and rings were not very good. I don't know that I would trust the rings to hold the scope on any gun with even a small amount of recoil. My scope had issues but the replacement is on a BB gun with different rings and it is doing ok.

[mpbby]

In Oct/2012, several stores by here were announcing the Nikko Stirling Mountmaster 4x32 AO mil dot as "airgun rated up to 27 joules" ("20" fpe).

My first one has got the windage turret stuck; in a month and with my Whisper X tuned for gas ram ("45"kg). 
Warranty.., the second brand new one had its reticle broken in a month with my other Whisper X ("50"kg).

In a "warranty deal", I'm still waiting (out of stock) for the model Gold Crown 4x32 AO mil dot, announced as "airgun rated up to 42 joules" ("27" fpe).

I still couldn't find out the technical source those "resistances" came from ..

As a recent information I've got, in both models the reticles are wired; source = Tactical Scopes (UK)

[Redharris]

Although still I have that NikkoStirling Scope that I referenced in the first post, after reading the responses I got, I decided to give another chance to my stock Centerpoint scope. I have shot quite a few pellets through the gun today, and it seems to be holding Zero, so far. I will continue to Test as the week goes by. I'll post my results next weekend.

[Redharris]

OK....I finished testing out my rifle/scope.....Fired it a few times during the week and just finished shooting again this morning.
Good News for me!. The Point of impact has not shifted all week. The scope is holding firm.

Originally my POI was shifting Plus/Minus approximately 5 inches up or down at 25 yards.
I figure that equals out to about +/- 20 inches at 100 yards. I figure I had the scope near its Maximum adjustment
for elevation and the reticle spring was probably not tight enough to secure it, hence my groups kept shifting around.

Long story short, The rifle/scope combo is functioning well as a SYSTEM and I am now happy.
In the last couple weeks I learned a lot about the particulars of scope mounting and break barrel pellet rifles.
Mounting a scope on a pellet rifle, and getting it to Work, can be frustrating. But if you do some research and approach the thing in a methodical manner you will have success.

[mpbby]

Research, method and perseverance.
Congratulations!

[Redharris]

New Update.......

After a couple weeks,,,,the POI  abruptly shifted again.
One moment the pellets were right on target, and then the next moment I was 2-3 inches off ........
After that,,,,POI was here, there, and Everywhere. AHHHHH!

Anyways,,,,I went directly to the Pyramid Air website and ordered a BKL one piece scope mount, and waited patiently for delivery.
A week later and $60 lighter, I installed the mount and scope on my rifle and went for a spin. Rifle shot Great! Very small groups at 25 yards and POI is not shifting about.

I did not Touch the scope adjustments. I just dumped the old mounts in favor of the new one piece, bolted the scope on, and went for a shoot. The rifle shot within about an Inch of POI and is holding steady. This leads me to suspect that my Rings were the Culprits,,,,, not the Scope. However,,,,I've been Fooled Before. So I will continue testing for a few weeks before I pat myself on the back....Lol.

On a side note: This BKL mount looks Very sturdy. It has BKL's patented one piece Pinch mount and 6 screws securing it to the dove tail. I dont think this thing is gonna move around on me. Here's a pic.