What distance for tuner testing?

[64Rambler]

Less...it should happen in about a half of a revolution on my std cf tuner. The light model takes a bit more. Just shoot that test I posted a few posts back. It covers 15 marks and the standard tuner has 32 per revolution.

edit...I went back and saw that you're using a different tuner. There can be significant differences in different designs, so there's really no way I can answer your question definitively. But, that test, or a modified, probably longer version of it, will show ya how far it is with any tuner. But it may well take some effort to get there in regard to establishing mark values and how they correlate to group shapes etc. I spent countless hours and thousands of rounds testing for these things. It wasn't a coincidence that my tuners have the number of marks on them that they do. In fact, the standard 7oz tuner has 32 and the 5oz model has 10. Big difference in that 2 ounces of difference in weight. Again, testing is why that is the case. Not random at all.

Hi Mike, your comment "it wasn't a coincidence that my tuners have the number of marks on them that they do. In fact, the standard 7oz tuner has 32 and the 5oz model has 10. Big difference in that 2 ounces of difference in weight. Again, testing is why that is the case. Not random at all." has me intrigued.
I built one to see if there was an effect and if so, I'd buy a real one.
Not knowing what I was doing, I just drew up a quick sketch, put a piece of stainless in the lathe and went at it. Finished part weighs 4.13 oz. and has 5/8"-24 threads, and I had a friend laser marks "0" thru "8" with long lines and short lines in between, so 10 marks per rev - seems like I'm closer to your 5 oz model except for the thread pitch. Does it sound like I can stick with those marks? I can also make a DYMO label with just about any increment needed.
I should be able to get to the range sometime this long weekend and send back the target.
Thanks for your input here.
Scott

 

[gunsandgunsmithing]

Hi Mike, your comment "it wasn't a coincidence that my tuners have the number of marks on them that they do. In fact, the standard 7oz tuner has 32 and the 5oz model has 10. Big difference in that 2 ounces of difference in weight. Again, testing is why that is the case. Not random at all." has me intrigued.
I built one to see if there was an effect and if so, I'd buy a real one.
Not knowing what I was doing, I just drew up a quick sketch, put a piece of stainless in the lathe and went at it. Finished part weighs 4.13 oz. and has 5/8"-24 threads, and I had a friend laser marks "0" thru "8" with long lines and short lines in between, so 10 marks per rev - seems like I'm closer to your 5 oz model except for the thread pitch. Does it sound like I can stick with those marks? I can also make a DYMO label with just about any increment needed.
I should be able to get to the range sometime this long weekend and send back the target.
Thanks for your input here.
Scott

The only way to know is to test. I can't answer that. Tried calculating it on my light model and missed it by a country mile and still have no idea why the calculation was that far off from real world results.

 

[64Rambler]

Made it to the range this morning, but will probably have to repeat this. I didn't have enough brass from one annealing session (AMP not in budget at the moment) to do this and noticed a difference in seating pressure between the 2 sets that I had available - All the same lot, though. So now I have all my brass fired and can anneal all 300 cases in one session. 6BRA, Alpha brass, N150, 30.2 gn, 107 SMK +0.006" (1.860" CBTO with my comparator)
Order of fire - small target; first 3 shots on clean cold barrel with elevation adjustments, 2X fired brass, 6X fired brass all on '0', Long target; '-1' to '5' (on 6X fired brass) - Line Break - Small target Lapua BR fire forming load on setting '6' (2 shots), long target '6' to '(1)0' (on 2X fired brass), then Lapua FF on '3' Far left, 3 shots). For the 36 rounds fired for the tuner settings, avg vel 2854, ES 21, SD 4.7.
Shot over "flags", but the gentlemen a few benches down had proper flags that didn't move a bit.

 

[64Rambler]

This is curious to me, if I may ask what inside diameter is the comparator you’re using and what is the freebore of the chamber ?

I will need to check with a gauge pin, but a Derraco "24" comparator (measures 0.2325" with calipers) and 0.120" FB (Criterion 6 BRA). It's a couple thou more now with 1480 rounds

 

[64Rambler]

This is curious to me, if I may ask what inside diameter is the comparator you’re using and what is the freebore of the chamber ?

A 0.2315 plus gauge pin fit. A 0.2325 plus did not. A 0.2320 minus pin fit, but not the 0.2330 minus.

 

[Bill Norris]

Made it to the range this morning, but will probably have to repeat this. I didn't have enough brass from one annealing session (AMP not in budget at the moment) to do this and noticed a difference in seating pressure between the 2 sets that I had available - All the same lot, though. So now I have all my brass fired and can anneal all 300 cases in one session. 6BRA, Alpha brass, N150, 30.2 gn, 107 SMK +0.006" (1.860" CBTO with my comparator)
Order of fire - small target; first 3 shots on clean cold barrel with elevation adjustments, 2X fired brass, 6X fired brass all on '0', Long target; '-1' to '5' (on 6X fired brass) - Line Break - Small target Lapua BR fire forming load on setting '6' (2 shots), long target '6' to '(1)0' (on 2X fired brass), then Lapua FF on '3' Far left, 3 shots). For the 36 rounds fired for the tuner settings, avg vel 2854, ES 21, SD 4.7.
Shot over "flags", but the gentlemen a few benches down had proper flags that didn't move a bit.

Looks like 2 3 4 would be a tad more stable than 8 9 10 on the tuner test.

 

[64Rambler]

Looks like 2 3 4 would be a tad more stable than 8 9 10 on the tuner test.

Yes, I think I got a full sine wave from -1 to 5 (which was one set of annealed brass). I liked 3 as its the top, but need to explore half marks... after I get annealing and neck tension under better control.

 

[JFrank]

A 0.2315 plus gauge pin fit. A 0.2325 plus did not. A 0.2320 minus pin fit, but not the 0.2330 minus.

Thanks, I was just thinking that 1.860 bto is about .050 more than I’m seeing, leading to my question…