Home Forums Reloading Big Game Rifles Loading for light barrels

Do light barrels benefit from reduced power loads?

I picked up a Howa Super Lite and was wondering if lighter loads would be better

No, not IME.

A lightweight barrel is no different than any other barrel in regards to handloading. Work up your load, and let the rifle tell you what it likes. That is true for every rifle ever made.

I’m going with “NO”! The reduced loads may help keep the barrel cooler for a longer shot string before the groups open up!


In a hunting scenario, where light barrels (rifles) shine..…I really try not to shoot long shot strings! memtb

Light Bbl's benefit from reduced strings and frequency.

3-5 shot groups, and then let the Bbl. cool.

Prefer single-base powder as well.




GR

Yes sir, three shot strings and let the barrel cool off in between, bring out few rifles and rotate.

Just to consider the physics involved, a light barrel will move/deflect more than a heavy barrel for any given force. It is generally acknowledged that barrels vibrate/oscillate in a pattern somewhat like a tuning fork when fired. Heavier loads will generate greater forces and therefore cause greater vibrations/ oscillation than light loads.

Thus it would follow that groups from a light barrel will be smaller with light loads on average than with heavy loads as the maximum excursion induced in the barrel harmonics will be reduced.

The period, amplitude, and even the exact shape of the oscillation may vary, but the fact remains, whether with a light barrel or a heavy one, that groups shrink when the bullet exits at the anti-node of the oscillation.

Sorry, but that is a load of bull.

I've got three light barreled rifles (7-08 & 30-06). All three will put two shots almost touching and the. third anywhere from two to five or more inches away. Seems worse with heavy bullets. Resting the barrel seems to help, maybe(?), but I can't shoot even a three shot string. Frustrating because the first wo shots routinely are subMOA. This phenomenon occurs across five or six powders and three to five different charges of each powder. Thoughts?

Free-floated barrels?

Fliers usually indicate bad bedding, a bad load, a bad scope, or a bad barrel. Not a light-weight barrel.

Seems like fliers due to these things you mentioned would occur randomly. That’s not what is happening. Two shots touching to near so followed by a “flier”, over multiple combinations of powder and charge and three rifles.

This is quite clearly true. I did not say that light barrels could not be tuned to shoot well, only that a heavier load would by the nature of physics impart greater excursions in barrel vibration amplitude and therefore would be more critical of tuning or more difficult to tune than a similarly well developed load using a lighter bullet or load generating less force.

Should you doubt this to be true, short range bench rest competitors for example, almost without exception, use light for caliber bullets. I suspect if heavier bullets were as easy to tune they would be used to provide what minimal advantage in wind drift they would provide- even at short range.

There are many factors at play, and no one is saying you can not tune a light barrel to shoot well with a heavy load- only that it is easier to develop an accurate load if the forces generated by that load are less. Reducing a load in of itself would not make it more accurate it still needs to be tuned.

Not necessarily. Bad barrel bedding can cause a variation in pressure on the barrel as it heats up, for example. A bad scope might hold zero for a couple of shots, and then shift internally, causing double grouping. Etc.

I would be surprised if you are consistently getting shots 1 and 2 nearly touching, and shot 3 a flier. Are you sure of that consistent ordering of shots? And it's the same in all rifles?

Random fliers are really just a statistical indicator of the larger group size that is characteristic of the mechanics and load. If you shoot enough shots, you'll see that the random fliers make up a larger cone of holes.

I think you may be confusing the pressure of a "heavier load" with bullet weight. The oscillatory amplitude is dependent on pressure (and therefore force), but not directly on bullet weight. I think you may also be overestimating the difference in amplitude between a load that generates, say, 65k psi and one that generates 58k psi. The difference in the resulting barrel oscillations may be small enough to get lost in the noise.

The example with BR competitors doesn't necessarily support your statement, as there may be other reasons to use light bullets instead of heavy ones. Another possible explanation could be that longer bullets require faster twist rates, which induce gyroscopic deviation from the macro path of the bullet, due to internal bullet eccentricity, which opens up the group enough to matter in the BR game.

I do not disagree with anything you are saying Jordan. However, if you were to choose to tune ten .243s and ten 6 x47s/Dashers/6XCs/6BRs with the same bullet - which do you think would would do the best? Even given components of the same quality I don't think the .243 would come out on top. But I do think the .243s would probably do better than 24 Noslers or 240 Weatherbys on average.

Many factors at play but in my experience I can generally get a fussy rifle to shoot better groups with a light bullet and a fast powder at a moderate velocity than the same rifle shooting a max load (either max velocity or heavier bullet or both)

YMMV

Also, in short range BR the BC of the projectiles may not matter as much as for long range competition. So shorter/lighter projectiles also generate less recoil which aids shot to shot consistency on the bags.

Major mechanical issues.

A thought from someone, that’s not nearly as educated on this subject as many of you! So please humor me.

Could a light barrel benefit from “full-length” bedding, in that, with the much shorter barrel being unsupported by the stock lower the amplitude of the barrel? In other words……smaller barrel cycles, due to a much shorter section of unsupported barrel, which may help smaller groups as the barrel heats! memtb