Actually, I do not see where I introduced a second variable in my experiment, as I have avoided annealing for the last couple of cycles, so at least 1000 rounds, if not more. This weekend, the only variable that changed was the barrel, and it was a huge change.
As for your question about neck tension, you are absolutely correct in stating that it's a very difficult variable to measure. Some of the folks are using hydraulic seaters that measure pressure. I think that's a measure too far for me. The way I presented it to the group recently is that it's important to have a good tension but the difference between requiring 20PSI to push the bullet out or 40PSI is mouse nuts when you figure the pressure pushing the bullet is above 60,000 PSI. I know some of the guys on the Australian team use .005 or more of neck tension and load to astronomical pressures. They use up the case in one single firing. They do very well, sometimes. I have increased my neck tension in 2017, I think it was. I now use .003 and considering going one more to .004.
Never forget that in F-Class, velocity is highly prized and we are always looking for the next accuracy node. You surely can have accuracy and good brass life, but that will be at more sane pressure compared to some of the stuff we produce.
I have not given up on annealing, but for now, I'm relegating it to the side.
|Knows too little |
about too much
TL Davis: “The Second Amendment is special, not because it protects guns, but because its violation signals a government with the intention to oppress its people…”
Remember: After the first one, the rest are free.
A couple of updates.
I continue to bypass my annealer but one thing that I decided to check was how much work my regimen was giving to my brass.
My match rifle has an extremely thigh chamber and freebore, and while I do not turn my brass, I only ever use Lapua brass in it. So, I pulled out my case guage for .308 Winchester and slipped in my newest (7 times fired) loaded cartridge. It slipped in just fine. Then just for kicks, I slipped in a 7 times fired, and not yet resized piece of brass. It slipped in all the way with the slightest of pressure at the end.
Even my fired brass fits into a guage. That's how little the neck is worked in this rifle. And resizing without an expander ball means, very little work during sizing. This is why I don't think I'm getting any benefit from the annealer at this point. The cases are getting ready to be dumped as the primer pockets are becoming a little loose. It's not surprise seeing my load is a couple of grains over book max.
In other news, I have been using the Autothrow along with the AutoTrickler in my powder measuring and yesterday, I had another session when I loaded 100 rounds with that setup. It went extremely well, it was quick and on point. I added a 3 foot by 3 foot plastic shield in front of the scale to ward off the A/C and the walking around and that was the best $4 I spent.
I ordered the V3 upgrade for the AutoTrickler and AutoThrow from Adam. Delivery should be some time next week. One of the new features is the ability to set the target weight from you smartphone via Bluetooth. That will make me happy. Also, the new stand for the trickler will allow for better control of the dispensing.
More info when it comes in.
So this weekend we had a 1000 yard match with eTargets. One of the side benefits of using electronic targets is that you get an idea of the velocity of the bullet at the target.
Looking at my strings, I see that my bullets are coming in right around 1460FPS on average, right where JBM says they should be and more interestingly, the SD of my bullets terminal velocity is in the single digits. That is very satisfying; shows that my handloading is adequate and my bullet preparation (pointing) is paying off.
I ordered the V3 upgrade kit from Adam when it was first announced in May. I received my package earlier this month and installed it on my A&D scale.
The stuff is solid. I love how you can set your target weight via an app on your smartphone/tablet that communicates with the electronics in the scale via Bluetooth. I used the setup to load a quick ladder test consisting of 6 different loads. It was quick, easy and painless.
After the test was done, I loaded up 70 cartridges with the selected load and the V3 Autothrow/Autotrickler dispensed a charge, to the kernel, every 10-12 seconds automatically. This is absolutely great. I used to dread the powder measuring process, and now, it's a lot of fun. (Yes, "fun", I am strange.)
I'm very impressed by how so much more efficiently I can process my brass and produce world-class match ammo compared to how I started handloading, 38 years ago.
I noted earlier on another thread that I had not detailed my sizing die setup, so I thought I would do that now.
In a rifle chamber there are two dimensions that are important: headspace and case length. Another one is overall length especially for magazine fed rifles but we will leave that one aside.
Headspace is the distance between the base of the cartridge (the face on the bolt) and a datum point somewhere on the shoulder of the bottleneck case. Yep, headspace is not an issue in straight cases.
The datum point is in the specs of the cartridge and in the case of my old friend, the .308 Winchester, this spot is somewhere in the middle of the should at the point where the OD measures .400 inch.
When you use a virgin case for the very first time, it will expand to fill the chamber and thus obturate the bore and then snap back a little. SAAMI has specs for the headspace for each cartridge and you can certainly use that as your guide. That's what I do for handloaded ammo that can be used in more than one rifle. But for this one, I want to use my chamber's dimensions.SO, the first firing will allow the case to grow somewhat, but it's not quite at the real chamber's dimensions.
Before we go any further, let me introduce you to my friend the Redding Instand Indicator Headspace and Bullet Comparator device. It sits permanently on my T-7 press. What this device does is that it measures the headspace by the simple expedient of putting a case in the shellholder and lifting it into the indicator. The dial on top will show you the measurement.
The indicator is cartridge specific, meaning that it comes with a case without a neck, set to SAAMI specs and the shoulder contactor will be at the proper diameter for contact with the shoulder.
What I do is I have the indicator setup with the SAAMI case and then I measure a virgin case. Invariably, I found the virgin case to be at the low end of the SAAMI tolerence. After the first firing it will be further along the tolerance range, but we're not at full chamber yet. After the second firing, we will be at chamber size. I then set the dial indicator to that size on the high end and .002 below on the low end. I then set up my sizing die so that a resized case will show up on the dial in that narrow range. Longer and it will be a tight bolt closure, shorter and it may lead to misfires.
A great way to test for a completed cartridge is to remove the firing pin from the bolt and then loading a cartridge in the rifle and closing the bolt. If you did it correctly, it should close easily.
It's been a while since I've been here and with the China virus running rampant in the world, there has not been any shooting competitions for the last few months.
However, as the situation eases or at least as we adjust to it, we are preparing to restart matches at our local club early in June. So, time to dust off the loading equipment and get some ammo loaded. Yay.
I have been resizing lots of brass since I had not been keeping up due to the virus stuff. I have been punching out a lot of spent primers and tumbling brass after sizing to get the Imperial Wax off and get clean shinny brass.
I discovered that it is important to check the sizing die setup using the comparator that I described above. For some reason I need to tweak it every few months. My press sits in a room in the garage and it's subject to variations in temperature. When we are talking about thousandths of inches, I believe the temperature needs to be considered. I last checked in December when it was in the 30s-50s and now that we are in the 80s-90s, I found that I was pushing the shoulder down a few more thous than in December. Lesson learned. Check all continually.
This morning I had a marathon loading session where I charged 300 cases with Varget and seated A-Tip bullets to finish. The Autotrickler and Autothrow combo worked flawlessly on top of my A&D FX120 and I was measuring powder to the kernel. I have a couple of matches coming up including Texas LR Championship and I wanted to get ahead of the curve.
That autotrickler and its partner the Autothrow are truly the bee's knees.
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