Load development question with barrel tuner

[bllistc]

So I understand that muzzle brakes, silencers, etc will affect your load development and POI. But as far as getting consistent SD/ES goes, is that only dependent on the individual barrel?

I’m asking because I have a magnetospeed sporter that I usually use for load development but I put an ATS barrel tuner with a hellfire muzzle brake on my barrel so it will not fit on the barrel. Could I take the brake and tuner off and just work up a load with low SD/ES and then put the tuner back on to fine tune the POI? Intuitively I wouldn’t think the muzzle devices would have an effect on velocity deviance but I don’t know for sure.

 

[BLKWLFK9]

It doesn't. take the tuner off and run your powder charge ladder test, choose your powder charge, throw tuner on barrel, and either only tune the load with the tuner, or run seating depth ladder test with tuner on "0" then once you find a good seating depth, use the tuner to see if you can tighten it up even more. But a tuner will not affect speed's.

 

[marchboom]

I would get a chronograph that you shoot over. IMO, anything that you put on the barrel affects harmonics and group size. When I do load development I do it one time exactly the way I will shooting the rifle. Why shoot the loads twice?

 

[1moaoff]

Mount it to the stock or chassis

 

[BLKWLFK9]

I would get a chronograph that you shoot over. IMO, anything that you put on the barrel affects harmonics and group size. When I do load development I do it one time exactly the way I will shooting the rifle. Why shoot the loads twice?

That's why you don't shoot for groups when doing charge weight test. That's what the seating depth test and tuner test is for

 

[marchboom]

That's why you don't shoot for groups when doing charge weight test. That's what the seating depth test and tuner test is for

Maybe the way you do it.

When I do load development I start out with trying different charge weights and see what groups the best. I can eliminate charges the don't group well. With the remaining charge weights that did group well, or show promise, I do testing of seating depth.

 

[John Glidewell]

When running a tuner I don't care about groups during development. I only care about SD/ES. Once I am satisfied with load I will shoot 2 and and dial tuner until they start touching. I go to 3 shots and keep tuning until it shoots a nice group. I go a little past to see it open and then fine tune coming back. I just did this with a new rifle. Shot 3 5 shots groups ES of 9, 11 and 9. shot all of the remaining 27 tuning rounds over lab radar during tuning process and ES was 23 for all 27 shots recorded. One shot pulled it off and I am sure that was me not getting powder charge right as I load in back of my truck on gempro 250, I hate driving back and forth so I built a portable load table for the back of my truck. I pulled that one shot and ES was 13 for remaining 26 shots, so I am happy with load. Powder drop and neck tension needs to be right in order to keep ES down.

The whole point of a tuner is to get rid of all that extra work. Pick a seating depth, find a charge and tune - done. I do not see any need to do anymore work. I took 3rd in our season opener with that rifle not having any dope for it. Little sloppy to start but cleaned the final stage and squeaked out 3rd. I am not doing a damn thing to this gun accept shoot it.

I have not seen a difference in speeds without tuner. I do run muzzle break at very least as I think that may show an effect on muzzle speed, esp with muzzle in front of radar. Cannot say it for sure as I have never testing it. But I have shot numerous rifles without tuner and added it after without any issues on speed or ES numbers.

 

[kthomas]

When running a tuner I don't care about groups during development. I only care about SD/ES. Once I am satisfied with load I will shoot 2 and and dial tuner until they start touching. I go to 3 shots and keep tuning until it shoots a nice group. I go a little past to see it open and then fine tune coming back. I just did this with a new rifle. Shot 3 5 shots groups ES of 9, 11 and 9. shot all of the remaining 27 tuning rounds over lab radar during tuning process and ES was 23 for all 27 shots recorded. One shot pulled it off and I am sure that was me not getting powder charge right as I load in back of my truck on gempro 250, I hate driving back and forth so I built a portable load table for the back of my truck. I pulled that one shot and ES was 13 for remaining 26 shots, so I am happy with load. Powder drop and neck tension needs to be right in order to keep ES down.

The whole point of a tuner is to get rid of all that extra work. Pick a seating depth, find a charge and tune - done. I do not see any need to do anymore work. I took 3rd in our season opener with that rifle not having any dope for it. Little sloppy to start but cleaned the final stage and squeaked out 3rd. I am not doing a damn thing to this gun accept shoot it.

I have not seen a difference in speeds without tuner. I do run muzzle break at very least as I think that may show an effect on muzzle speed, esp with muzzle in front of radar. Cannot say it for sure as I have never testing it. But I have shot numerous rifles without tuner and added it after without any issues on speed or ES numbers.

I'm not really sure how a tuner reduces load work - it's very simple to load up a few rounds of different bullet seating depths. Replacing that with a tuner is simply replacing one step with another one, it's not a reduction in steps. Arguably there's more potential pitfalls with a tuner, but that's not the point of this thread, so I'm not going to go down that rabbit hole.

I agree with many posters here in that if you can't use the tuner in conjunction with your magnetospeed, then do your velocity testing with the magnetospeed to dial in ES/SD, and then after that you can fine tune precision through bullet seating depth and/or tuner settings. When I personally do load development, velocity and precision are done independently of each other, as I've found that I can get really good ES/SD through powder charge, and from there I can fine tune precision with bullet seating depth (I've personally haven't seen any benefit of using a tuner with reloads, and most benchrest shooters do all their load workup without a tuner, FYI).

Don't sweat it if you can't use your tuner and magnetospeed at the same time for load development. You can develop a very good load without using both items at the same time.

 

[marchboom]

The reason I don't like attaching a magneto speed to a barrel is that it affects barrel harmonics, Just like a tuner. So as soon as you take the magneto speed off the barrel you have changed the harmonics.

I keep it simple and use a chronograph that I can shoot over. The magneto speed type of chronograph is just adding another factor into the equation.

A question: How does a tuner affect ES/SD?

 

[John Glidewell]

A question: How does a tuner affect ES/SD?

to my knowledge, it does not