can't figure out what is wrong with new build

[trickyric]

I recently built a .308 rifle with a Remmington 700 sps AAC-sd action and barrel, an AI stock and Jewell trigger. I put a Leupold Mark 4 sight on it and a Quicksilver .308 suppressor.

OK here's the problem:
after about 40 rounds on 3 different range sessions the gun starts to lose zero to the point of almost a 2 feet.
I have sighted in the rifle and locked the zero, moved the dials and then returned to zero and it works. We have tested with the suppressor on and off and it works.
I am getting very frustrated and any ideas would help.
The rifle is plenty hot after 20 rounds but it takes between 40 and 50 to go instantly way off.

 

[jbell]

Re: can't figure out what is wrong with new build

Is the shift the same direction by about the same ammount (approx) each time?

 

[trickyric]

Re: can't figure out what is wrong with new build

it has been consistent as to where the new zero is but since it's only been a few sessions I am not sure if the problem is always in the same place.

 

[maccrazy2]

Re: can't figure out what is wrong with new build

If the mount and rings are tight and nothing is moving, try another scope

 

[Cologgi]

Re: can't figure out what is wrong with new build

Have you checked the barrel to see if its free floated? I would think it is something to do with the barrel. Also, I would make sure the crown is good.

 

[ColbyLang]

Re: can't figure out what is wrong with new build

My BIL had a similar problem with his Mark 4. His was a turret problem though. The further he cranked from zero, the reticle actually moved to the left. When he would return it to zero, it was off. He sent it back to Leupold, no questions asked, they replaced it. Oh, and he bought it used too

 

[jbell]

Re: can't figure out what is wrong with new build

It more than likely sounds like a scope issue. Inless if you let the rifle sit and cool very well after the shift and it then returns back to zero then it could be a barrel not floated (or something like that).

 

[trickyric]

Re: can't figure out what is wrong with new build

I think it's a scope issue myself. Since all the parts are new it's gonna take time to figure it out.
I am going to shoot the suppressor on a another rifle Wednesday. If that isn't a problem I will try a different scope on my rifle Friday.
After that I am going to have to get the entire build checked.
It's an Accuracy International stock and a Remington action. That is pretty much a drop in with 2 screws and aluminum bed.
It's frustrating!

 

[trickyric]

Re: can't figure out what is wrong with new build

The weird thing is we checked the Zero.
We set the zero, cranked the dials, returned to zero and they worked.
After it moved, we did it again with the new zero point set and it returned to the new zero point.
ughhh!

 

[Engine 22]

Re: can't figure out what is wrong with new build

How does it shoot without the suppresor? Does it stay on zero or shift also? Do you have a different scope to try on it?

 

[trickyric]

Re: can't figure out what is wrong with new build

It held zero without the suppressor but at a different point of impact. We checked the zero without the suppressor, moved the dials and then moved them back to zero and it held. We then put the suppressor back on and it held zero in a different impact spot on the target with a good group.
Weird!

 

[trickyric]

Re: can't figure out what is wrong with new build

Ok,
Tried the Suppressor on a friends rifle. It worked perfectly so the that is not the problem.
Next step is to try a different scope.

 

[Engine 22]

Re: can't figure out what is wrong with new build

What scope base and ring set-up are you using? Have you properly torqued the screws on the mounting system? How about the action screws- torqued?

 

[trickyric]

Re: can't figure out what is wrong with new build

Ok problem solved.
We took the entire rifle apart and put it back together. All we can think of is one of the screws wasn't quite seated straight.
But after shooting 100 rounds, testing the dials and the suppressor we are all good.