Wow! Lots of info!

[elarges]

The bench issue came up because of the location of my groups. I hold pretty tight groups, but they tend to be slightly high and left. I wanted to shoot from a bench to see if it was the sights, or if it was my trigger squeeze or follow-through.
The problems arose when the groups I shot from a bench were all over, with no rhyme nor reason for their pattern.
If the groups continue to be tight, but high and left, shooting offhand...I will probably just bag the bench-shooting (no pun intended), and adjust my sights per my offhand grouping.
Sound like a plan?
:hmm:

 

[Landngroove]

Are you saying that your shots were all over the place, or grouping high and left, from the bench rest?

 

[elarges]

The bench gave me shots that I could barely keep on the paper. Offhand gave me the tight groups I was looking for, but a touch high and left.
At 30 yards, the balls might stay tight enough to keyhole, but the group is about an inch and a half high and the same distance to the left.
I'm not sure if it's my trigger queeze and follow through, or if my sights are off.
Being as the location of my groups is pretty consistent, I'm thinking about adjusting my sights, even if it IS because of the way I shoot.
Who knows?!?!?!

 

[davy]

The bench gave me shots that I could barely keep on the paper. Offhand gave me the tight groups I was looking for, but a touch high and left.
At 30 yards, the balls might stay tight enough to keyhole, but the group is about an inch and a half high and the same distance to the left.
I'm not sure if it's my trigger queeze and follow through, or if my sights are off.
Being as the location of my groups is pretty consistent, I'm thinking about adjusting my sights, even if it IS because of the way I shoot.
Who knows?!?!?!

How are you holding your rifle on the bench? IMHO you should hold your rifle in the palm, while supporting the back of the hand on the bench, same support as offhand. NOT resting your barrel/forearm on the bench sandbag.

Ina a nutshell ... If you change your holding pattern between bench and offhand ... you will run the risk of changing your point of impact IMHO.

Davy

 

[Pittsburghunter]

If you do rest the rifle on a sand bag make sure you rest it on the forearm and not the barrel. Resting the barrel can cause some pretty bad shooting with a rifle who's barrel naturally floats somewhat.

 

[Landngroove]

I would think that from the bench, If you are using a good benchrest set-up, you should shoot pretty consistant, and off hand you would see inconsistantcy. I know, that being right handed, even though I have a pretty good benchrest set-up, if my trigger pull is hard, it is easy to move the gun ever so slightly right when firing. I try to be totally aware, of any movement I could make, when shooting from the bench. If you are sure there is no movement, in your bench set-up, then you could adjust the sight. Good Luck!

 

[JOHN L. HINNANT]

Greetings Ericlarges,

The typical ML hunting rifle, for what ever reason, does not always shoot well off of sand bags or a similar rest.

All of my rifles require that the forearm be rested in my hand, and the hand rested on top of the sand bags.

This method of holding also produces a zero that is the same as an off-hand hold.

Try this method of holding the rifle on the bench and see if your groups improve and can be adjusted the same POI with both bench and offhand position.

Best regards and good shooting,

John L. Hinnant

If you are not an NRA Member, why not? I am carrying your load.

 

[paulvallandigham]

John: I think this depends on how and where you rest the gun on the sandbags. For instance, I found that siting in my .30-30 Winchester lever gun only works if I rest the gun on the front part of the action, and not on the fore-end stock. If I do this, I get consistency, and no variation in POI from when I shoot the gun off-hand. If I rest the gun on the forestock, the groups shoot high.

I have found the same thing with some half-stock muzzleloaders. The closer to the trigger guard you place the rest under the gun, the more consistent the groups, and POI. I have tried to glass bed the barrels on guns and checked to see if this eliminated this, and it helps, but has not eliminated the differences you note. I believe we are dealing with the Harmonics of the barrel, ie. the vibration waves in the barrel as the projectile moves down the barrel. Just like plucking the string on a harp, or a taut rope, you get waves of vibrations. That is why muzzle weights that can be adjusted are so useful to "Tune" modern gun barrels for small groups. If you interrupt those waves by putting a stop somewhere along the barrel, your POI is Likely to change.

 

[JOHN L. HINNANT]

Greetings Paulvallandigham,

All of your comments are quite correct. Too many shooters are not aware of all of these things.

Another factor is weight of the rifle. The lighter the rifle weight, the more attention has to be paid to consistently hold the rifle the same way for every shot.

Over the years, I have witnessed many shooters take a fine shooting light weight centerfire rifle and turn it into a 3-4 inch grouping rifle at 100 yards. All because of poor benchrest techniques.

Once had a fellow swear that rifle from a fine gunsmith was no good, and he wanted me to "fix it". To make a long story short, this 11 pound varmint rifle would easily shoot half minute angle groups at 100 yards for me, but only 1 to 1-1/4 for him.

Never was able to convince him his bench rest technique needed improving.

To this day, he thinks the first gunsmith knows nothing and I am an idiot.

Of course, my wife agrees with the second part, but she also does not shoot well off of the bench. (No seconding of that Davy or Rabbit03)

Another factor concerns resting the barrel or the forearm on the sandbags. There is a major difference in those harmonics here and a big difference in POI between bench rest and offhand shooting. In most cases, if the rifle is bench shot with the barrel resting on the sand bags, the offhand POI will be quite different.

I also think it is more difficult to get good accuracy if the barrel is rested on the sandbags.

When working with my cross-sticks rifles, I shoot off of a stubby set of cross sticks mounted on my shooting bench. In this instance, this is a major POI difference between the cross sticks rest and the sand bag rest.

As you say, harmonics, they can not be ignored. Your post is a good one with good points.

Best regards and good shooting,

John L. Hinnant

If you are not an NRA Member, why not? I am carrying your load.