Thread: The Howikka Test Bed

Originally Posted by gimp

A few reflections from me -

1. You've tried a wider range of powders than I'd generally consider, that's an interesting approach. As you note, with the bullet the rifle seems to like (the 77gr TMK) it is impossible to select between them based on.

- precision at this stage (with the results shown I don't think you can say that any of them are any different) or
- velocity SD (from 5 shots it's too unreliable to be useful for anything, and also for hunting inside reasonable ranges it makes no difference to hit probability unless it's incredibly bad)

You'll likely want to select a powder now based on availability, price, or velocity (it's not clear here how much headroom you have with each powder to get to a velocity target) - or have to re-test with more shots to establish any precision difference.

These could be assessed from a desktop exercise prior to firing - could you filter your powder choices a bit more to those that are likely to work well ? It does appear that bullet is a larger driver of precision than powder. In my experience the hierarchy of importance for precision, with a rifle that isn't defective -
1. Barrel quality
(a very large gap)
2. Bullet
3. Powder
4. Brass
(a tremendously large gap)
5. Anything else

I wanted the 75 ELD to work so tried every powder I would be happy to run to give the best chance of meeting this objective. It's saves time as i have to do less range trips. I'm time poor not powder poor. It's also provides good data if I in future have powder supply issues where to start an alternative powder load.
I agree 5 shots give me nothing conclusive but they can using inverse probability exclude things. Ie i know that the 75s are extremely unlikely to meet my desired requirements in any combination I would like to run as if they can't meet it with 5 it's exceptionally unlikely they will for 10. Until I change something significant with the rifle. Ie barrel to action torque, reprofiling, barrel swap, etc I won't bother testing 75 ELDs again. I agree regarding SD it was just noted as the data whilst unreliable is easy recorded with modern tech.

I am hoping to prove out a heirachy like yours to myself over time with more rifles.

All powders are worth considering but the results could have told me 1 or 2 were not worth continueing with. Ie im using small samples on an exclusion basis not a confirmation bias. In this case it didnt help much and i may find powder makes less difference and it never provides decent sorting at low sample size.

2. 5 shot groups provide some filtering but unfortunately not a lot as the central tendency means you're more likely to get an "ok" than a "bad" 5 shot group from an imprecise combination. The wide range of 5 shot filtering done allows you to rule out a few things really quickly, but doesn't allow you to rule anything IN . Does it really reduce component use given that the products that aren't ruled out are much more inconclusive than a 10 shot group - requiring more followup? For example, it's not clear whether or not any of the 77gr TMK results actually meet your defined precision requirement. A 10-shot group of any of those loads is likely to be in the range of anything from 0.7 - 2+ inches - more likely in the middle somewhere.

Similar to above agreed. And im not worried about component use if they arent in short supply.i find even range shooting is useful to gain trigger control etc and get comfortable with the rifle setup. Rounds down range will help try. Apply the fundamentals in a less stressfull environment. Obviously field practice is also required and arguably more important but harder to do.

3. The 5-shot seating depth test with 75ELD and H4895. The average 5-shot group size of these 5 groups is 3.1 inches. The largest is 150% of this, the smallest is 67% of this. Hornady's data suggests that you should expect 40-50% variation in 5-shot group size around the average group size. You're seeing results in this range - so while it tells you roughly that the rifle doesn't seem to like the 75ELD at all (unfortunately!) it doesn't seem to provide any evidence at all that the seating depth changes are providing any different precision than you'd expect from 5x 5-shot groups of the same seating depth. Very inconclusive. Good demonstration of the futility of fiddling with seating depth.

absolutely was good through to get 25 rounds to settle in to shooting. But i may repeat in the future at large sample sizes for interest sake

The 73gr ELDM may be worth trying. It seems more likely to shoot well in rifles that are "fussier" about which bullet they like.

I think they are actually tangent ogived like a TMK and yes they will get tried. I think if the 62 ELD VT shoot and terminally preform they will outperform the 73 signifcantly ballistically.

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Originally Posted by Stocky

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If you're time, rather than component, poor maximizing the efficiency of your time makes sense. I'm still leaning towards the view that more samples of a narrower range of things would do that...

I would be possibly concerned that the 62gr ELDVT may be the point at which you find insufficient penetration in some circumstances with .224". I really like the 60gr Vmax for goats and would expect similar performance, and those frequently exit goats with spectacular results. Goats however are small and not terribly difficult to kill, 40gr .224 bullets in the shoulder penetrate sufficiently. Interested to see results.

I think any trigger pulling probably helps if you're mindful and use it to embed fundamentals.

I was curious about the 75 ELD after your results. I've never shot them from my rifle, but I built it intending to use them. In the initial load development kiwi Greg did, he reported that they didn't shoot as well as the 80s - but that was based on 3 shot group testing. The 80s worked so well I never bothered to load anything else until a year ago. But I had a box of 75s on the shelf and figured I'd try them, because they seem to be quite fussy for many people. Book max 2206H with some dirty mixed lot PMC brass, cci450, at whatever rando seating depth my die is set for the 80s. 2810fps, SD of 12.7 over 10, and precision about the same as the 80s - and about the same as everything else shot through the rifle - the cut rifled match barrel really seems to pay off in that it will shoot almost any bullet, handload or factory, very well.



So the 75s work ok in my barrel.