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View Full Version : developing a now 30 cal hunting load



Wadestep
03-27-2015, 07:53 PM
this is the first load I have 'worked up' to this degree for cast boolits. so, I am asking those with more knowledge for tips and to make sure I am going about this the right way. I want this to be my hunting load next season for Florida whitetail and hogs.
Boolit: NOE 188 gr 30 cal hunter
rifle: S&W I-bolt 30-06 ( after last hunting season, gets called 'The meat stick')
twice used, random 30-06 brass, neck sized
powder: varget - amount listed in writing in pictures
COL: 3.075
CCI standard large rifle primers
lead mix: 30% linotype, 70% range scrap
distance: 85 yards

results:
135210
135212
135213
135214
135215
135216
I think 34.0 and 34.5 were good, 35 was opening up, 36 was over the top. I plan on working the load in smaller increments as per what I wrote on the 34.0 plate. O rmaybe 33.5 to 34.5 in small increments.

Am I going about this the right way? any pointers/suggestions?
wade

Yodogsandman
03-27-2015, 08:16 PM
For accuracy, test with just one brand of brass.

How did you arrive at your C.O.A.L? Seating depth changes could dial it in further.

Wadestep
03-27-2015, 08:21 PM
I understand about the 1 type of brass. However, I didn't have 30 of the same type on hand when loading them. At this point, my COL is just a guess based on a similar-type boolit in the Lyman manual and also what I found online. There is no rifling engraving on the noses. Maybe I could push it out a bit farther. However, should I get the powder level dialed in first or change the COL? Too many variables changing at once and I wouldn't know what made the difference...

DrCaveman
03-27-2015, 08:27 PM
Im not much of an 'expert resource' but i think you are doing well

Finding rifle accuracy nodes is something im planning to work on this spring & summer...there will be velocities that just plain work for your barrel length & stiffness, and there will be quite a few of them, separated by harmonic relationships. I.e, if 1400 shoots great, 2800 will probably shoot great. Also 2100 would probably shoot well, and the halfway points between those (1750 & 2450) might also shoot well.

People seem to report that increments of the 200-300 fps range identifies a solid accuracy node. If physics is involved (which i think it might be) then the increments would not be linear up the velocity scale, but rather based on percentage changes. I think the 200-300 fps stories are believable because the velocities tested are pretty close together so the percentages are not that different. It's not like we're talking sonic frequencies where many orders of magnitude are covered.

Long story short, it seems like you found accuracy nodes at 34 grains and maybe 33. If you had a chronograph you could record the velocities of these loads, and then do a little math to figure where the next accuracy node would be found. Or, just work around the 34 grain load, adjusting loads by the 1/10th grain until you see one ragged hole. Thats probably the better route.

My notions of 'accuracy nodes' only work if the boolit upset/rifling engagement are the same at all velocities, which i think is only true using jacketed. Still, barrel harmonics are not imaginary.

Everything is just vibrations, some much much faster than others. Those we percieve are pretty slow in the grand scheme of things.

Wadestep
03-27-2015, 08:42 PM
Thanks for the reply, I think I'm basically trying to find a 'node' up near the max velocity/RPM that the lead can handle. 35 grains Varget seems to be over that. My guess now is to work up at .2 grains next trial. I wish I had a chronograph, that would help a lot, but it's not in the cards right now.


Everything is just vibrations, some much much faster than others. Those we percieve are pretty slow in the grand scheme of things.
Sounds like Quantum Physics.... or was that String Theory?

largom
03-27-2015, 08:54 PM
Random brass will have different case capacities and thus give different velocities for the same powder charge due to different pressures! If you need 30-06 brass I will give you some, just pay postage.

Larry

Bjornb
03-27-2015, 09:10 PM
Definitely use uniform brass when testing loads. Your better groups (33 and 34 grains), assuming your rifle has the most common I-bolt barrel length (23 inches), are only running 1730-1790 fps according to Quick Load, so you can safely increase to at least 37 grains (1950 fps) while adjusting seating depth.

Try a few with the bullet seated hard into the lands. Above 1950 fps you can expect less accuracy, as you are spinning the bullet above 140K and accuracy is harder to come by above that RPM.

DrCaveman
03-27-2015, 09:12 PM
I dunno, i just call it 'life' looked at in a mathematical way. Some things we see (fast vibrations) some things we hear (medium vibrations) some things we touch (slow vibrations) and some things we 'feel' (unknown speed of vibration). Those things in the feel category are toughest to characterize, and they include intuition, emotion, religion, instinct, etc.

Fortinately the internal and external ballistics of firearms are well within the predictable realm of ordinary physics, operating at mid-level speeds for those of us living in the real world. That doesnt mean that it is easy to nail them down, but at least it is feasible.

Electron motion within atoms? Planetary movements? I find it crazy to think that people are actually trying to predict those things, so far out of our realm. Still, they do it, and do it pretty well. More power to them, ill stick within the several dozen various octaves that we humans have been graced with the ability to perceive...now if i can just spell that last word right, ill sound real smart!

Good shooting to ya, im taking notes for my Varget tests in 30-06 and 30-30. Please keep s posted with resulta

Yodogsandman
03-27-2015, 09:28 PM
Thanks for the reply, I think I'm basically trying to find a 'node' up near the max velocity/RPM that the lead can handle. 35 grains Varget seems to be over that. My guess now is to work up at .2 grains next trial. I wish I had a chronograph, that would help a lot, but it's not in the cards right now.

Sounds like Quantum Physics.... or was that String Theory?

You might have your lead alloy maxed out already for velocity. Your groups have opened up. My Lyman#4 listed min start load of 31.0 gr (1656 FPS) and a max load of 39.5 gr (2132 FPS) with Varget using 195 gr boolits (311679).

You could oven heat treat and quench your boolits to get you closer to max velocity.

Your alloy is antimony rich, you could cut that amount of linotype in half prior to making boolits for heat treating.

Blammer
03-27-2015, 10:02 PM
take your 33.5 and 34gr results, load half in one charge and half in the other and go shoot them again. that will give you a good idea of the loads as the brass will surely be mingled on both sides.

you plan looks sound to me.

Larry Gibson
03-27-2015, 10:09 PM
Thanks for the reply, I think I'm basically trying to find a 'node' up near the max velocity/RPM that the lead can handle. 35 grains Varget seems to be over that. My guess now is to work up at .2 grains next trial. I wish I had a chronograph, that would help a lot, but it's not in the cards right now.

Sounds like Quantum Physics.... or was that String Theory?

You found the RPM Threshold for your components. Different brass would not account for the enlargement of the groups you experienced. Excessive RPM would.

Larry Gibson

Wadestep
03-27-2015, 10:16 PM
Got it. I'm trying for more uniform brass. I was looking for more than 1700-1800 fps ( based on Quickload per BjornB). Hoping to get near the 2,000 mark, although it may not be needed or possible. My hunting distance is at most 200 yards, usually <100 yards. I'll also look at what COL it takes to seat into the rifling/lands.
thanks for all the help so far, lots of info here.

grouch
03-28-2015, 04:43 PM
I'd agree with the suggestion that you go back to 33.5 and 34 and try them again. It looks to me like you're close to a node(not much point of impact difference and good groups). Suggest you try those two with a longer test, try seating depths close to or barely touching rifling, and if you can live with that velocity level, try 18-20:1 lead and tin for a softer alloy and better expansion. For what it's worth, you should easily achieve that velocity with the soft alloy. Also, I seriously doubt that testing by smaller increments of powder charge will gain you anything.It won't take much of a temperature change to vary velocity more than1/2gr of powder. Hope some of this helps.
Grouch

catskinner
03-28-2015, 07:34 PM
Try 34-35 gr. and shoot at least two groups at those levels. Also try varying overal length. However for a hunting load I would ensure easy chambering and extraction. It is no fun leaving a bullet in the barrel when unloading. Cartridge oal might be limited by magazine length unless you want to hunt with a single shot.