Home Forums Hunting & Shooting Ask The Gunwriters Rifle Accuracy

While playing with a new rifle, and fighting some accuracy issues, it's made me really think about what makes a rifle accurate? By accuracy, I mean relatively small groups, which is really just consistency. Getting the same result each time the trigger is pulled. Leaving the shooter out of the equation for this discussion, because I have a good idea of how much of the inaccuracy is due to me.

What can move a rifle from a 1.5-2.0" shooter to a ~.75" shooter?

What makes a barrel accurate? What is it about the construction that will allow it to respond differently, or impart some inconsistent force on the bullet?

Inconsistent contact on some part of the barrel, or even action, is an easy one to see. Bedding and ensuring no contact on the forend should prevent that. Likewise ensuring the mag is not doing anything weird would be important.

Bolt lug contact. What if both aren't touching? Even that seems like it would respond the same each time. Apparently not?

What about the bolt face? I hear about squaring the bolt face. Savage uses the floating bolt head to ensure it aligns each time. What if a bolt face is a bit off?

What else?

are you shooting factory ammo or handloads?

if handloads, try shooting a "known load" - for me in general I like Sierra Game Kings and H4350/4831...generally one or two grains off max.

Run the OAL 2/1000's off the lands (*cup and core only...not mono metals)...

If that doesn't work, then try bedding the action.


If that doesn't work, consider selling it.

Shooting factory. .308 Federal Gold Medal Match, 168gn.

I understand variables in hand loading impact accuracy. I guess I want to better understand the 'why' behind the hand loading variables, but also the rifle itself.

As for bolt lug contact. Savage 340's only had one lug. I've had 4 of them in .222, .223, .225 and .30-30. All were capable of sub MOA accuracy.

Proper glass bedding should be the first step. Freefloat the barrel or some rifles like to be FL bedded. This may require a little experimentation. Hand load your own ammo. Consistency in and dialing in your handloads is a key ingredient to ringing out every ounce of accuracy. You don't need to shoot match grade bullets/ammo to get excellent accuracy out of your rifle (hint).. Minimize TIR/runout in your ammo. Chamber dimensions, rifling, lands, bore dimensions, crown and overall health of your bore affect accuracy. Consistency in everything (including shooter skill/form/habits) has an influence in accuracy...

I've seldom seen glass bedding markedly improve accuracy.

You don't know how to properly glass bed a rifle then..

That's a real group.

I've built custom rifles that sold for 3500.00 and my customers were satisfied. I currently build custom 1911's that sell for 2500 - 4,000.00. My employers apparently think I know what I'm doing as they keep paying me every week. I think there's a good chance I can bed a rifle about as well as anybody.

I have.....and I do mean markedly!

I did say seldom. Not never. It has been rare.

A good trigger adjusted right is the first thing I'd do. I don't agree with the advice to seat bullets .002" off the lands. That's close enough so that some could be in the lands, and others not.

prm this may be an over simplification but I feel a gun that has been #1 bedded correctly w/#2 a good crown and a #3 a good barrel should shoot around a half inch w/several different loads. I have only 1 rifle of a cabinet full that will do it. To me, time of bullet in barrel and consistent barrel vibrations w/the bullet leaving the barrel at the same key point each time matters...a bunch. I think some people are lucky and get a shooter doing some of those things but not many. It does start in the bedding to me. When one realizes how little a rifle has to move to pull a shot an inch at 100yards he'll be well on the way to getting accurate, consistent shooting. Of course hand loads that have .002 or less run out is a must as well. powdr

A good barrel,good bedding and good construction.If it's not built correctly,a rifle will not shoot well.

I agree that with a good barrel and bedding a hunting rifle should shoot three shot groups in the .5"-.75" range. Maybe a bit more if limited to factory ammo. But what is it about a barrel that makes it good? As a barrel maker, what are you paying attention to when making the best barrel possible? What aspects of the construction does a competition bench rifle maker focus on?

Being much lighter and fired off basic bags using factory ammo I certainly don't expect bench rifle results, but I want to do what I can to make improvements.

This is not an apples for apples discussion.
There are vatrious groups of opinion here and they are independent of each other in requirements.
1. Handloaders
2. Factory ammo
3. Accurised rifles
4. rifle platform

1 - Handloaders want the best accuracy and the top velocity
2 - Factory ammo likes accuracy but compromises on velocity
3 - Accurised generally means within the capability of the user or check book
4. Rifle Platform is more attuned to rifle sum part component specs.

Accuracy can be a fluke and it can be created. I have seen factory rifles out shoot customs, most of us have.
I have made accurate rifles by building them to a spec.
I have tweaked both factory and built rifle to gain accuracy improvements or as some would say, consistency in the best accuracy obtained, simply meaning reliably in uniform groups.

The rifle itself is a torqued platform consisting of layers that each can have detriment with accuracy.
layer 1 - action screws
layer 2 - floor plate
layer 3 - stock
layer 4 - bedding, both action and barrel and trigger cut out and bolt recess and tang mortise.
layer 5 - barreled action
layer 6 - Magazine box
layer 7 - scope bases
layer 8 - lower rings
layer 9 - scope tube
layer 10 - top rings
layer 11 - top ring screws.

Everything is torqued and while attention is given to bedding and barrel floating, all else can be troublesome and create a binding or torquing within the lock up that can tension the stresses within the lock up.

After all this, we have the variables like muzzle crown, barrel profile in relation to the cartridge, trigger settings, ergonomics of the stock design, shooter stance or pressures applied to the stock and rifle platform during the shot and the big one.........scopes.

Be prepared to toss an expensive name brand scope in the trash and accept what is, as money doesn't guarantee what you thought you would receive.

Notice I have not mentioned the load yet.........

How much accuracy do you want? an MOA rifle is a good rifle to some and inadequate to others.
Most accept .75 MOA but would like .5 MOA. Are you good enough to shoot that well?
If you want better than .5 MOA, be prepared to spend money and not stop until you get there and then that achievement is only as current as that particular barrel wear on that particular tube.

It is as hard or easy as you make it remembering that in most instances, the majority on here are talking about hunting rifles, not bench rest rigs.

prm,

If you can borrow a copy of RIFLE ACCURACY FACTS, by Harold R. Vaughan, it will tell you more about what actually affects accuracy than asking questions on the Campfire for a year. I wrote "borrow" because they're rare and expensive. Vaughan is an actual rocket scientist who did extensive technical lab work to put the book together.

There are some other good books that provide good information, including several on modern benchrest and target shooting, because they not only address the rifle itself but the realities of how shooting technique can affect accuracy. Three that come to mind are THE ULTIMATE IN RIFLE ACCURACY by Glenn Newick, EXTREME RIFLE ACCURACY by Mike Ratigan, and THE RIFLE SHOOTER by David Tubb.

In addition there's some good stuff to be learned from Warren Page's old reference work, THE ACCURATE RIFLE, and most of the books by Bryan Litz, though they involve exterior ballistics (especially at long range) more than the rifle itself.

I am quite pleased with .75 MOA from a hunting rifle shooting off of simple bags at the range. Some days a bit better, some days worse.

Mule Deer, Thanks for the recommendations, they appear to be exactly what I'm looking for. I really want to better understand the 'why' behind what is happening.

A barrel makes or breaks a rifle in my opinion. I half agree with Blackheart...bedding only helps if there were a bedding issue prior. I have several factory rifles that are not bedded and shoot lights out. If an action is a poor fit for the stock, then obviously bedding will make a difference.

Don't forget the Book of Rifle Accuracy by Tony Boyer. The most winning shooter in benchrest history.