Horizontal stringing in .243

[CRNA]

Give the rifle a tune up, that is Glass bed the action with one inch of the barrel, free float the rest of the barrel and adjust the trigger pull at around three pounds. Pore groups are most often inproved after a tune up. Check the bolt locking lugs to see if each lug shows about the same amount of contact but only two of the rifles Iv worked on need the luggs lapped.

Thank you for the advice. Maybe she just needs a little TLC to really start to shine.

 

[sendero72]

I'm having the same problem with my little savage 243 testing 105 amax with Superformance powder. I have to allow at 3 minutes between shots or the sporter barrel will heat up very fast. The barrel is floating fine, trigger is Ok but nothing to brag about. There are 3 screws to set the barrel.....is there a particular order in tightening these screws to the stock???

 

[Bart B]

As for the 3-5 in the ground - it's to get your barrel heated up, you will almost always notice this on any gun, floated, blue printed, anything... when your barrel is warm is when you shoot your groups, to get the best groups.

There are hundreds (thousands?) of competitive shooters who know that's not true. I and others have shot super accurate rifles starting with cold clean barrels and putting 20 to 30 shots downrange and point of impact doesn't change. One test of such heating started with a cold barrel and 20 shots later, each fired at intervals of about 30 seconds, all 20 went inside 3.5 inches at 800 yards. Done the same thing with a 30 caliber magnum putting 30 shots inside 7 inches at 1000.

A friend put 57 shots fired from the same .308 Win. case into 1/3 inch at 100 yards starting with a cold barrel. Shots were fired about every minute as he was full length sizing the case each time and making measurements of it. That barrel may well have fried an egg if one was put on it.

Anytime point of impact changes after the barrel heats up the problem is usually in the receiver. It's face ain't squared up with the chamber axis. The high point puts more pressure on the barrel at that point when metal expands from heat causing the barrel to whip differently as more shots are fired.

The other probable cause is the barrel's not stress relieved properly. As it heats up, the stress lines cause it to bend. That makes the muzzle axis point somewhere else after heating than when it was cold.

Proper fitting and stress relieving of good barrels prevents zero changes as the barrel heats up.

 

[B-RAD]

We are strictly taking about a sporter barrel.

 

[Bart B]

We are strictly taking about a sporter barrel.

Don't care what type of barrel it is. They all perform the same when fit and stress relieved or not. Only difference is one shoots better groups than another.

There's two other reasons why shots string horizontally. One's the shooter's trigger finger is in or out too far on the trigger lever. Not enough pushes the rifle to the left (for right hand folks) and to the right if in too far. The other's called "finger flicking." The trigger finger's not held back fully until the rifle stops moving from recoil. A natural tendancy is to flick one's finger off the trigger as soon as they feel it break and the energy from doing that gets transferred to the rifle...horizontally while the bullet's going down the barrel.

 

[41mag]

I have to go with Bart on this,

During a load work up for a stock Sako Forrester in .243, the bottom two 5 shot groups were fired in 80+ degree weather at 100yds, one after the other only waiting long enough to rechamber, and reacquire the bull. I was specifically looking to see if it would change impacts as it heated up. The first three fell right in but the other two climbed out as the barrel heated. The spot on the right is for foulers, after cleaning. These were both shot with a cleaned barrel and one fouling shot prior to shooting the group. The barrel was ambient when we started.

I had swapped out the stock, with a newer factory one I got from a friend. I figured it might have to be relieved some, and since, it has been. I don't have newer pic's but it holds them all together now with this same load.

The barrel got hot enough from those initial five shots that we had to wait close to half an hour for it to get back to ambient. It would have been fine for most all hunting we do, but when we catch a bunch of hogs out in the open 5 shots goes really quick, and I wanted to be sure they all went where we were aiming.

 

[jerrschmitt]

I'm with Bart. In addition, I'd check the bedding. Slopping factory bedding, which is very common, will cause impact shifts.

All of this being said, a factory rifle, with a cheap scope and cheap ammo can't be expected to do much better than what your photo shows except on the internet where all rifles shoot 1/2 inch groups or better, all day long, if the shooter does his part.

 

[ken snyder]

It is not a single source problem. To me it looks like the rifle wants to shoot. When I see groups like this I tell the shooter to get more comfortable. The shooting position is causing too much strain, generally just bench heighth and the leaning angle that is necessary to get into the scope. An example: with your rifle in a firm rest and without touching it, look in your scope and move your head up and down then side to side, you will notice the crosshairs walking across the target. Get lazyboy comfortable in a position that promotes exact repeatability. It looks like your a good shot with good skills shooting from an uncomfortable position. Bet ya lunch that 1/3 of the grup size will go away.

 

[Bart B]

IIn addition, I'd check the bedding. Slopping factory bedding, which is very common, will cause impact shifts.

Well, I'm not sure about that. As long as the bedding holds the barreled action the same for each shot, zero shouldn't change.

Accuracy is all things being repeatable. Best accuracy's attained when the range of where things repeat their behaviour is very small.

 

[ken snyder]

Hello Bart. There is more happening than just comfort. Factory ammo, barrel temp, bed and all of the good tricks of the trade. My observation is that the group looks as if there is the real possibilty that he is shooting 2 different groups, each with the same concerns that need to be addressed. In the photo I saw a good shot with a rifle that needs some help to strut its stuff. And a shooting position that yields 2 different groups. The no cost remedy of comfort vs. accuracy. One of several things that bothers me personally is correcting a rifle and having it come back exhibiting the same but reduced problems. At this point we go shooting and with a little reminder to take a little more time to set up lazyboy comfortable, a large portion of the problem goes away allowing me to properly understand the rest of the story. It does not matter what my conclusions are, but this one is observable and free.

 

[CRNA]

It is not a single source problem. To me it looks like the rifle wants to shoot. When I see groups like this I tell the shooter to get more comfortable. The shooting position is causing too much strain, generally just bench heighth and the leaning angle that is necessary to get into the scope. An example: with your rifle in a firm rest and without touching it, look in your scope and move your head up and down then side to side, you will notice the crosshairs walking across the target. Get lazyboy comfortable in a position that promotes exact repeatability. It looks like your a good shot with good skills shooting from an uncomfortable position. Bet ya lunch that 1/3 of the grup size will go away.

I can understand what you are saying, but I just don't think that's the case. Here is a group I shot on the same day not more than a half an hour before I started with the .243. Shot off the same bench, same height, same target area, even the same bipod. (7mmRM)

 

[ken snyder]

It looks like I was correct about you being a good shot! The large grouping from the offending rifle looks like it is shooting 2 different points of Impact, each one seperate from the other, along with consistant rifle concerns. Kind of like 2 different people shooting the same rifle. However your dime sized groups with a different rifle, kind of blows my thoughts of bringing the group(s) together clear out of the water. ( you demonstrated its a non-issue for you). Still looks like the rifle can shoot wth a little help. I know you understand that I don't want to be like the car mechanic that replaces everything under the hood before he discovers its a clogged gas filter.

 

[jerrschmitt]

Well, I'm not sure about that. As long as the bedding holds the barreled action the same for each shot, zero shouldn't change.

Accuracy is all things being repeatable. Best accuracy's attained when the range of where things repeat their behaviour is very small.

That's my point. Sloppy bedding won't hold the action the same for each shot. Even in a light recoiling rifle like the .243 the barrled action can shift around in the stock under recoil.

 

[B-RAD]

Kinda funny... I'm almost in the same position..

Just bought a .223 Rem Tactical with B&C stock for 500$ at a gun show last week - Shot groups today, 5 shots total and I got more than 1 set of 3 shots in 1 hole and 2 shots in 1 hole, so there are 2 holes on the paper out of 5 shots... but... the "2 holes" are over .450" center to center apart... As today was the first day shooting. other wise I'm looking at .100-.200" 3 shot groups.. So I gotta figure this out... little ****ed..gun)