Is this Vertical Stringing

[zerobarrier]

Hello all,

I shot my new rem 700 today and these are my groups: Specifics below pic

My question is, is this vertical stringing? If so how do I fix it? I did a search on it and it seems it can be mechanical or poor shooting technique. The first target was me sighting in. Target 4 and 5 are pretty much a straight line. I am rather new to precision rifle shooting, so my technique may suck. I used a bipod with no rear bag. It is a heavy barrel free flated in a bell and carlson A5 stock. The rings are torqued to 15 in/lbs on scope and 50 in/lbs to bases. Bases are torqued to 50in/lbs and the action screws are torqued to 55in/lbs all with blue loctite. Any opinions or advice is welcomed. Thanks

 

[Joshua M. Smith]

Hello,

Yes, it is.

Is the barrel contacting the stock? Bull barrel or standard? Some Remmy 700s have pressure pads on the stocks near the end to tame down barrel harmonics.

Shooting one with that pad without letting it cool will cause what's happening.

Regards,

Josh

 

[back40]

how quickly were the groups fired? group 4 and 5 definitely look like vertical stringing, however the others just look like you need a little more time with the rifle. how accurate are your powder charges? get yourself a rear bag, they work quite well.

 

[Vern Humphrey]

First of all, wrap a thin piece of paper, like a dollar bill, around the barrel and slide it down to the receiver. If it will slide all the way down to the chamber reinforce, the barrel is free-floated. It won't, the barrel is not free-floated.

If the barrel is free floated, take a piece of cardboard, like a business card, and put a bit of it in the barrel channel, then tighten the screws. If this improves your groups, either leave it like that, or use a bit of bedding compound to make a pressure pad where the card was. Some people like two small pressure pads, one about 4:30 and the other at 7:30, forming a sort of V-block.

If the barrel is not free floating, try free-floating it -- use a dowel near barrel size, wrapped with coarse sand paper and work until your dollar bill passes all the way down to the chamber reinforce.

 

[Walkalong]

Differences in shoulder pressure will cause vertical stringing.

 

[zerobarrier]

I can slide a piece of paper all the way down the barrel to the chamber. The Bell and Carlson stock has an aluminum v-block bedding. I fired al 20rds within 20 min. While firing each group I shot, ejected brass, inspected brass, loaded 1 round, took 2-3 breathes, then breath hold, then fire.

 

[zerobarrier]

It is a bull barrel, Rem 700 AAC-SD, powder charges good, I use a new dillion electronic scale to check the weights

 

[strambo]

Probably shooting technique, try using a rear bag.

 

[Casefull]

You did not mention caliber...also I would try some groups without the bipod. A firm grip on the fore end with a support under your hand. Also try moving up and down with powder loads. I was surprised recently with my 300 wsm. It started grouping decent with the hotter loads.

 

[taliv]

next time you shoot, right before you take a shot, when you are settling in and getting ready to pull the trigger, pay special attention to the reticle movement. is the reticle moving mostly up and down? is it moving in a pattern? (i.e. with your breathing, or with your heartbeat) or just kind of randomly wandering?

 

[Joshua M. Smith]

Dumb question:

Has it always done this, or did it just start? Or is it a new build?

Regards,

Josh

 

[Joshua M. Smith]

Even dumber questions:

Does the recoil lug bottom out?

Does the recoil contact make firm vertical contact with the stock?

Is the chamber area floating?

What happens if you cut a couple, say, 20 thou shims and move the action up a bit, then fire a couple strings? Does it settle down?

What are you taking the screw torque to?

Josh

 

[243winxb]

used a bipod with no rear bag.

Bags front and rear is how i would test.

 

[zerobarrier]

Josh it is a new build. 55in/lbs for action screws. I do not know the answer to the rest of your questions.

 

[zerobarrier]

Taliv the reticle moves around almost in a circle pattern, I can't seem to get it perfectly steady

 

[zerobarrier]

it is a 308 winchester. I am starting to think it is my technique. Like I said I am new to shooting from a bench trying to get groups of 1 moa or better. I think I may just need practice.

 

[back40]

there are some great articles out there on marksmanship. natural point of aim, breathing, trigger control, etc. if you have a .22lr, it can be a great aid in getting you to practice proper technique.

 

[rcmodel]

used a bipod with no rear bag.

Theres your problem.
Use a rear bag so you can't move the gun.
Get square behind the scope so your eye is perfectly centered in the image.
Hold it the same every shot.

This will stop that vertical stringing foolishness.

rc

 

[bullzeye8]

Yeah watch your trigger control and also breathing. Breathing affects your up and down a lot. Inhale then exhale halfway and stop. Take your shot. Then finish exhaling. This way you have a few seconds that your body is not trying to get oxygen or get rid of it so you can be the most steady.

Also try some different charge weights because maybe that charge had a higher extreme spread for speed causing that so try a couple different charge weights and maybe one will settle a bit better

 

[Steel Horse Rider]

This pattern is related to breathing and body position, horizontal stringing is due to flinching or pull problems. Practice is the answer to both problems.

 

[GLShooter]

Not only technique but it is often the load wanting ac tad more velocity. I have had the same results and bumping the charge helped tighten things up nicely.

Greg

 

[zerobarrier]

Ok thanks guys. I think I will just need to practice. I was worried it might have been a problem with my rifle or scope. I think the charge weight is good. I went from 40grs-43grs in .3 increments and at 42.7 grs I shot a .5in group twice.