I have a Sako TRG 42 338 Lapua with a NightForce 5.5-22x50 scope, which I shot with the muzzle brake removed, so recoil is heavy but very managable. Today I setup at 400 yards and took my first cold bore shot, and to my amazement the shot hit 8 inches high! This never happens, I've got this rifle dialed and I shot it a few times a week. The rifle is zeroed at 400 yards, so lots of shots have been taken at this range. So I dialed the MOA down 1 and took a few more shots, and now its hitting low of the POA. So I dial up 1/2 MOA and its hitting good again. I shot a few groups and decided to dial up another 1/4". The next shot went 8" high!! So I dialed back 1/4 and its back down 8". Dialed up 1/2 and its way up there again. Does this mean my scope is pooched, and its time to send it back to NightForce for some surgery? This is very disappointing, I figured this scope would hold up to the heavy recoil...has anyone else had this type of issue with a high end scope. Any advice is much appreciated. Thanks guys.
Strange issue with my Sako 338 Lapua and NF 5.5-22 x 50 scope
- Thread starter datatools
- Start date
ultimate_monkey
CGN Ultra frequent flyer
- Location
- victoria BC
best way to check the scope would be come back down to 100yds, fire 5 shots poa/poi. then dial up say 4moa reapeat and so on while keeping your POA the sameyou should end up 4/5/6 (how ever many groups you fire) distinct groupings, if you have groups mixing in with each other, and you end up with what just looks like 1 big viritcal sting, you may want to look at having the scoped check out by NF
also as weird as it sounds check your action screws, it might explain some of the irational shooting iregularities
also as weird as it sounds check your action screws, it might explain some of the irational shooting iregularities
What changed from the time you shot the rifle last, to the time you shot it and had these issues? Cleaning? Disassembly? Something must have changed. If you did nothing, and I mean absolutly nothing, since the last time you shot it, then do as recommended above to see if your scope has sh&t the bed. I find it unlikely, but it is possible that your NF has issues.
R.
R.
Your scope check method sounds good, ill give this a try and see what happens. I highly suspect the scope is pooched, but I'll confirm. The last time I shot the rifle it was about minus 10, today it was minus 2. The cold bore shot is usual the high one, but never anything this drastic. I checked the action screws and all is tight, scope rings and base are all tight too. I'll be disappointed if it turns out to be the scope, maybe time for an upgrade, but to what? What is better/more durable than a NightForce??
S&B maybe. Have you checked the impact with the brake back on? - dan
ultimate_monkey
CGN Ultra frequent flyer
- Location
- victoria BC
have you been hand loading?
and if so at what tempiture did u develope the load? and with which powder? as we all know some powders are more tollerable of tempiture changes then others, so if it was say -15 when u came up with your loads now its up to almost 0 that 15* can drastically change the way powders act..
and if so at what tempiture did u develope the load? and with which powder? as we all know some powders are more tollerable of tempiture changes then others, so if it was say -15 when u came up with your loads now its up to almost 0 that 15* can drastically change the way powders act..
I didnt clean the rifle or make any changes to it since shooting it just a few days ago. I then cleaned the rifle and tried it again with similar results. The scope has approx 1500 300 WinMag and 500 338 Lapua rounds under is belt.
I've been shooting my Lapua on a regular basis and have not changed my load (I handload with IMR4350 83gr Sierra 250gr HPBT). I've been testing to see how temperature changes the POI from minus 25 on up. The last few weeks have seen about 200 rounds through the rifle with regular cleaning intervals (about every 30-40 rounds). I shoot on a regular basis and have not experienced a problem like this yet, today was a surprise.
This is my only Sako TRG, and the scope mount is the Sako one piece unit and I have 3 rings attached (the rings have a plastic insert in them to reduce the size I guess??). Its a beefy, heavy duty unit
I dont think the base or rings or action screws are to blame because it shoots great groups until I adjust the MOA up/dows a 1/4" within my zero zone. As soon as I get out of that area its seems to work OK, but I need to test more to draw a conclusion. If I get time tomorrow I'll try shooting the box and post my result.Mystic Precision
CGN Ultra frequent flyer
- Location
- Summerland, BC
I am no way trashing NF. It is a machine and machines break.
Get it warranteed and odds it will not happen again.
All scopes can have mechanical failures.
Jerry
Get it warranteed and odds it will not happen again.
All scopes can have mechanical failures.
Jerry
Thanks very much Mystic. I will contact NightForce today and determine how to send the scope back for warranty work. Just out of curiosity, is this a common issue to happen with a NightForce scope? I would very much like to have a failsafe scope, and am now considering an upgrade to S&B??
That does not sound like nightforce at all. But as mystic said, its a man-made product. It doesn't matter how much money / time / effort you put into a product, it can still have a flaw and fail.
I don't think switching brands is going to get you any further ahead. If you were looking for an excuse to upgrade, then I guess you have found one. Otherwise, confirm the error and get warranty.
I don't think switching brands is going to get you any further ahead. If you were looking for an excuse to upgrade, then I guess you have found one. Otherwise, confirm the error and get warranty.
