Barrel harmonics obstruction

[17remhunter]

I read that when working up a new load at the bench you should always use a front rest bag and never a bipod mounted in your rifle because the bipod with interfere with the harmonics of your barrel has anyone heard this?

 

[44hunter45]

Is the bipod mounted to the barrel or to the forend sling stud?
Do you intend to have the bipod on when hunting?
Are you going to have the stock off and re-torqued after you work up your load?
Do you use a MagnetoSpeed?
What is your barrel contour?

I think there are lots of things that can effect your nodes, but you can get lost in an OCD meltdown trying to manage them all.

 

[Mallardsx2]

I think there are lots of things that can effect your nodes, but you can get lost in an OCD meltdown trying to manage them all.

I have found this to be the case. Personally, when I stopped worrying about a 1 inch group at 100 yards I started enjoying my life a little bit more. Lol

 

[Addicting]

If your barrel is free floated then a bipod is a non issue. I’ve done a ton of load development and always use a rear bag and Harris bipod.

If your barrel isn’t free floated then there is a whole mess of harmonic issues that you need to deal with.

 

[Wind Gypsy]

Bags vs bipod can impact your groups or POI because of recoil management. If a bipod is loaded pretty hard vs shooting off bags is where i've seen the biggest difference. Some times shooting with a bipod can result in bouncing under recoil. Like others said, if a barrel is free floated i would think it's less of a harmonics thing and more of a how your gun moves under recoil before the bullet exits thing.

 

[jpc01101]

Two times now my Dad has called me to come to the farm because a gun that has previously been stacking bullet holes was shooting crazy. Both times he was sitting there with the barrel laying directly on a bag...don't do that. As long as you are resting on your stock all should be very similar. Also, although you didn't ask. I have a Browning X-bolt that is an absolute tack driver that when I put on a suppressor after the initial 3.5 MOA Adjustment it won't group near as well as without the suppressor. That is not an issue with my Christensen w/ carbon barrel. I can only assume the can is throwing off the harmonics of the barrel.

 

[Brian in Montana]

If the bipod is attached to the forend of the stock, not the barrel, there's no reason to believe it is changing the harmonics.

 

[17remhunter]

Is the bipod mounted to the barrel or to the forend sling stud?
Do you intend to have the bipod on when hunting?
Are you going to have the stock off and re-torqued after you work up your load?
Do you use a MagnetoSpeed?
What is your barrel contour?

I think there are lots of things that can effect your nodes, but you can get lost in an OCD meltdown trying to manage them all.

Yes, I use a Magneto Speed. Will that interfere with my nods and affect my groups??

 

[17remhunter]

I never thought that maybe my Magneto speed chronograph might interfere with my barrel harmonics and has an impact on my group size

 

[17remhunter]

I reload for my 17 Hornet and my 17 Remington. The 17 Hornet is a unaltered CZ 527 it shoots in the high .3’s Every CZ 527 Ive owned are incredible out of the box shooters. All loads were worked up using a front bipod attached to the sling stud

 

[Brian in Montana]

Yes, I use a Magneto Speed. Will that interfere with my nods and affect my groups??

Yes, the MagSpeed will change barrel harmonics and point of impact.

 

[Brian in Montana]

I use a Magnetospeed a good bit, but you can't really shoot groups to test accuracy while that bayonet is attached. Just use it when you need to get muzzle velocity. I sometimes use it for a 10-12 shot string for a ladder test, but then shoot some groups, without the MagSpeed, based on the results of the ladder test.

It's a useful tool, but it has some limitations.

 

[Addicting]

I never thought that maybe my Magneto speed chronograph might interfere with my barrel harmonics and has an impact on my group size

Never group with it. It is just for velocity. Map out your velocity where there is a flat spot in speed over .3-4 grains. Remove the magnetospeed, Load in the middle of that node, and adjust seating depth to adjust group size.

 

[17remhunter]

Two times now my Dad has called me to come to the farm because a gun that has previously been stacking bullet holes was shooting crazy. Both times he was sitting there with the barrel laying directly on a bag...don't do that. As long as you are resting on your stock all should be very similar. Also, although you didn't ask. I have a Browning X-bolt that is an absolute tack driver that when I put on a suppressor after the initial 3.5 MOA Adjustment it won't group near as well as without the suppressor. That is not an issue with my Christensen w/ carbon barrel. I can only assume the can is throwing off the harmonics of the barrel.

The barrel was on the bags but if the forend of the stock was on the bag thats ok. My original question was the difference between using a bag with the f

I read that when working up a new load at the bench you should always use a front rest bag and never a bipod mounted in your rifle because the bipod with interfere with the harmonics of your barrel has anyone heard this?

so their is no confusion. The LR author stated that when working up a load never use a bipod attached to the forend of your rifle stock. Alway rest your forend of your stock on a bag because a bipod mounted to your stock will affect your barrel harmonics

 

[Brian in Montana]

There shouldn't be any functional difference between a bipod or bags in terms of barrel harmonics, as long as its just the forend of the stock. In both cases the forward weight of the rifle is supported by the forend resting on something. Barrel harmonics aren't effected unless something is physically contacting the barrel itself.

 

[Wind Gypsy]

Two times now my Dad has called me to come to the farm because a gun that has previously been stacking bullet holes was shooting crazy. Both times he was sitting there with the barrel laying directly on a bag...don't do that. As long as you are resting on your stock all should be very similar. Also, although you didn't ask. I have a Browning X-bolt that is an absolute tack driver that when I put on a suppressor after the initial 3.5 MOA Adjustment it won't group near as well as without the suppressor. That is not an issue with my Christensen w/ carbon barrel. I can only assume the can is throwing off the harmonics of the barrel.

Might be harmonics. A little extra weight out front might induce barrel contact on the stock too? I know my xbolt stalker shoots well but that tupperware stock is quite flexible and can be sensitive to how i load it on a bipod.

 

[ropeup79]

I think it was already mentioned but using a bipod on a hard surface like a bench/table can cause weird bouncing during recoil.