Vertical Stringing!

[Kedron]

So, I took my rifle to the range yesterday and was pretty disappointed. At 100 yards it printed groups between 1.5"-2" that were pretty much straight up and down. In fact the horizontal group size was only slight larger than caliber. It hasn't done this one before so I am clueless as to where to start in correcting this problem. I was hoping some of you could help me with an order of things I should check while troubleshooting. Here are the specifics on my gun/load and shooting conditions. The gun is a savage 10fp
with the factory 24" 1 in 10 twist barrel. It is set in a Bell and Carlson Duramaxx stock that was my first attempt at bedding but has shot well in the past. I was shooting prone with a harris bipod. The load was a 168 smk over 44 grains of varget. This load usually groups .5-.75 moa in my rifle. I know there are probably a million things that could be causing this but I need a starting point. Any help would be greatly appreciated.
Thanks,
Kedron Thomas

 

[royinidaho]

Hmmmmmm, interesting,

Assuming (which can be a bad thing) that nothing has changed with the load and COL or the rifle, I'd check the following:

Bipod on tight
Bipod on solid dirt
Shooting position consistent from shot to shot. (This one drives me nuts)
Using a rear bag though my son outshoots me and he doesn't.
Elbows set properly for you
Pull the stock back into the shoulder with the trigger hand consistently.

I kind of flock shot here, as you said that it has done well in the past, I assume from the same position.

If the shots were progressively higher from first to last then bbl temp may be a consideration. Am assuming its free floated. Check the float.

Hope this helps at least a little.

 

[JR]

You never mentioned a chronograph reading...or consistency of string, was it climbing for group?

JR

 

[Buffalobob]

Was this the first time on a bipod?


Check action screws for tightness

Check for any foreign object that might have got into the barrel channel and affectign the freefloat like some halloween candy.

 

[Aussie]

E.C.
Not uncommon when shooting off a bipod in my 20 years of experience with them . I always hold onto the fore-end as I would if shooting the rifle offhand and pull it gently into my shoulder . This way your point of impact stays the same when shooting from different positions and vertical stringing is eliminated (unless you have another problem) .

 

[Kedron]

Thanks Guys, After what you've said I suspect it likely is the bipod. I was resting the rifle legs in gravel and its probable that they couldn't get a good footing. Also I was letting it free recoil as opposed to hanging onto the forearm. I guess I'm gonna have to work on my prone technique. I'll probably try to find a benchrest and some sandbags to just make sure something hasn't gone sour with the rifle or load.

 

[Charles A]

[ QUOTE ]
Also I was letting it free recoil

[/ QUOTE ]

Baaaddd... Also I wouldnt hang onto the forend. Just get your body straight behind the gun, use your offhand under the buttstock to control the sandbag, "preload" the bipod by pushing foreward slightly into the buttstock with your shoulder and pull the grip into your shoulder using your middle and ring finger. How hard you pull the gun into your shoulder is up to you. Some like a gentle firmness, I like a HARD hold. Expirement and see what works for you.