Sighting in Issue

[trolson90]

I’m at a loss so hopefully someone here has the answer. I was shooting my Ultralite in 28 Nosler today attempting to zero in at 200yds. I was on paper and finally had a group starting where I wanted it when I threw a flyer about 7 in low. I figured it was me so I shot again and didn’t even hit paper. Same with my next two shots. I then had my friend shoot and he couldn’t hit paper either. We went from a 3 shot 1in group to not being on paper in 3 shots and 4 min. We had let the barrel cool off but it was hot. I was running the Omega can from SilencerCo. All screws and bolts were tight on gun and scope. I did notice the bolt was hard to bring back but that was happening all day. I don’t even know where to start. TIA

[Alleycat72]

It's the stock. It flexes quite a bit. When you put the suppressor on, it will cause vibrations in the direction you moved the gun last. Do this, put your scope on It's highest power. Look through the scope and tamp the rear othe stock in the sandbag. Watch the crosshairs move up and down in a harmonic cycle 5 or 6 times.

[CFJunkie]

The only time I ever experienced anything like that was when I had a failure of the scope reticle.
It only ever happened once many years ago and it was with a pretty cheap optic back in the day when I couldn't afford expensive optics and was trying to find bargains.
I was also shooting loads close to Pmax back then and that might have exacerbated the problem.

I normally would have told you to check the scope rail screws (you might not have checked them yet since you would have to remove the scope ring), the ring mounting screws, and the ring screws holding the scope in the rings, but since you said the screws and bolts were all still tight, it sounds like a failure of something internal.

A hot barrel won't result in a 7 inch drop, even at 200 yards. A 40 deg. change in barrel temperature on my 6.5mm barrels will only cause about 1/4 inch drop at 100 yards at most.

[Robinhood]

What scope?


EDIT: I didn't see CFs post as I was posting mine but everything he said is spot on.

[Dave Hoback]

Same question I have.... what scope? And I agree with CF... only thing I’ve ever seen cause a 7” poi shift is the scope.

[trolson90]

I've got a Vortex Viper PST GenII 5-25x50 on it. I'm definitely leaning towards a scope failure. I'm planning on mounting another on it and trying again. I haven't had the chance to test out what Alleycat72 was saying, but if the stock is that bad then I would think I should have never been able to put a group together.

[trolson90]

When I got home I took everything off and checked all screws. Everything was torqued to recommended levels. I’m running a Viper PST GenII 5-25x50 and shooting Hornady PH 162gr. I’ll mount another scope on it and see if I can replicate the issue.

The only time I ever experienced anything like that was when I had a failure of the scope reticle.
It only ever happened once many years ago and it was with a pretty cheap optic back in the day when I couldn't afford expensive optics and was trying to find bargains.
I was also shooting loads close to Pmax back then and that might have exacerbated the problem.

I normally would have told you to check the scope rail screws (you might not have checked them yet since you would have to remove the scope ring), the ring mounting screws, and the ring screws holding the scope in the rings, but since you said the screws and bolts were all still tight, it sounds like a failure of something internal.

A hot barrel won't result in a 7 inch drop, even at 200 yards. A 40 deg. change in barrel temperature on my 6.5mm barrels will only cause about 1/4 inch drop at 100 yards at most.

[Robinhood]

You need something recoil tested or resistant. The Vortex scopes have been taking a beating lately with regards to durability.

[Fuj']

Not a fan of Vortex myself, but i'd tell you to leave it on, pull that Silencer, and do a proper
100 yard zero. Shoot 3 and let it cool.

[Rifleman#1]

My buddy had a vortex one of the crosshairs fell off completely

[Orezona]

I have one (Viper HS 4-16x44) on my .223 precision carbine. The first one out of the box had no horizontal travel. The second has been great and was simple to swap for at the store. I wouldn't put one on a rifle for an important large game hunt. For that, I'm Zeiss all the way. My personal theory is that Vortex lifetime warranty wouldn't help me on a quality hunt.

[Dave Hoback]

My buddy had a vortex one of the crosshairs fell off completely

Who... your buddy 99 K 30-30?? Or Larry Root?

[Fuj']

My buddy had a vortex one of the crosshairs fell off completely

The scoped in question has an etched glass reticle.

[trolson90]

I’ll try this too. My only hesitation for this being a fix is the fact I had a 1” group at 200yds with the silencer on already. Right before I started throwing shots. I should also add, right before this I had the gun on paper at 100yds without the suppressor. Not grouping since I was waking out to 200 but I was there no issue. This shows consistent shots with and without the suppressor before the failure.


Not a fan of Vortex myself, but i'd tell you to leave it on, pull that Silencer, and do a proper
100 yard zero. Shoot 3 and let it cool.

[Dave Hoback]

The scoped in question has an etched glass reticle.


Was thinking the same thing Fuj. But hey....why not bring up one of Vortex’s lower line of scopes, a COMPLETELY different model
from the PST the OP mentioned??

[Orezona]

I'm out. This thread is too serious for me. I retired to be able to enjoy shooting and reloading again.

[charlie b]

Solving a mystery is always good. :)

[want2ride]

The only time I ever experienced anything like that was when I had a failure of the scope reticle.
It only ever happened once many years ago and it was with a pretty cheap optic back in the day when I couldn't afford expensive optics and was trying to find bargains.
I was also shooting loads close to Pmax back then and that might have exacerbated the problem.

I normally would have told you to check the scope rail screws (you might not have checked them yet since you would have to remove the scope ring), the ring mounting screws, and the ring screws holding the scope in the rings, but since you said the screws and bolts were all still tight, it sounds like a failure of something internal.

A hot barrel won't result in a 7 inch drop, even at 200 yards. A 40 deg. change in barrel temperature on my 6.5mm barrels will only cause about 1/4 inch drop at 100 yards at most.

This is what makes sense to me. It just sounds too much like a scope or related failure to me.

I personally shoot a Blackhawk Wrath (9" .338 LM rated silencer) on my two Ultralites (one is a 28 nosler) and i never had an issue with the stock doing anything that unexpected. I also shoot off bags almost all the time, and rarely a bipod and that may be why i have less of a problem, but it is just a guess. but i don't plan to use a bipod while hunting so that is how i practice. I realize that the stock is the weak link in the rifle, but it just sounds more like a scope issue to me.

[Rifleman#1]

Just making a point. you guys are a piece of work. wont say what i really think because i cant. do you jump on everyone when they say something. makes you look soo smart. who cares what quality the scope is. just sharing a example good day. Maby Dave needs a hug!

[Rifleman#1]

O by the way finally found some Chuck Norris Pee for sale.