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Originally Posted by gitrdun
My experience is that I get extremely low run-out by first fire forming the cases in the intended rifle. Then run them through my collet die. After that, I turn the necks lightly, adjust the cutting tool just enough to get a full skim on the neck. Then I run them through the collet die once more. I actually dedicate as much time and effort for my hunting ammunition. It may not be desirable for others, but my personal way of thinking is that if I can turn out precision ammo for target shooting, why not do likewise for my hunting rounds. I roll much less hunting rounds that I do target rounds. I'm happy each year to have 20 precision rounds to hunt with. I realize that this does not fall into the needs of other hunters, and that's OK. We all take different approaches to our intended end results.  |
For years, after I started reloading, I did not even know about bullet run out or even consider the idea of turning necks. When I started loading for 7mm08 I would use my Remington 700 V, which had a tight chamber, to fireform brass which I would neck size with Lee collet dies and found that they fit every other rifle I loaded for. I fire formed and neck sized mainly to get the extra powder capacity that I needed in the Remington 7mm 08 case for my hunting loads. I really could not improve on the Remington 120HP factory ammo that I first used as it shot them like this:
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When I was able to buy new Remington Brass I started jamming a Speer 110 TNT into the neck, with the Lee seating die, after loading with enough Varget to push them to 3300 fps on a hot day. No Case Prep and they did a number on more than a few gophers as they shot like this:
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Neck sized Remington Brass was used to shoot the above group (upper Left) with a 162 A-Max at 600 yards. My first hunting loads were with a 140 &120 Nosler Solid base bullets before they became obsolete:
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When H 4350 (EXTREME) first came out my new Speer Manual #12 showed a compressed 48.0 grain load doing 2911 fps with their 145 grain BT in a rifle just like mine. I was able to come up with this uncompressed load in Neck Sized Remington brass that shot like this in nearly every rifle, there were many, that it was shot in. It shot the same even after I wore out the Lee Collet die and started using an RCBS three die set.
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One thing I found in common, with the best loads in the 7mm08, was that the bullets seated near the lands and the bearing surface of the bullets were ahead of the neck/shoulder junction. This coupled with a near 100% case fill is likely more important than case preparation and expensive dies, at least in my estimation.
When I started loading for the 204 R I soon realized that it was difficult to find good loads and realized that none of the above criteria was met with this design, and the 12 twist barrel did not help when trying to run 40 V-Max Bullets. I bought a 19 Badger in a Calhoon CZ527 that came with a set of FL Forrester BR dies that have a seater with the fitted flange like Redding die. It fit most of the criteria and shot very well with loads that Calhoon supplied. I looked into the 20 VT and found that it was not really what I wanted as it was destroying brass trying to get a 32 grain bullet to 3800 fps and was not designed to run the 39 40 grain bullets effectively.
I decided to do my own wildcat designs that met the criteria that I deemed necessary for success. Unlike conventional designs that have to be fireformed, which really can stretch new brass, I decided to form brass with custom dies that did not alter the new case dimensions. I then got a reamer cut to fit the formed brass with minimal tolerances and no movement of the shoulder. Brass is formed to the chamber with Zero or less than 0.001" Head Space and maintained by forming the fired brass back to its original size. This way there is virtually no stress placed on new brass, especially if pressures are kept low.
I form brass from larger caliber brass after turning, at a larger Caliber, which gives me cases with very low run out. In the case of my 20 EXTREME I turn 222 Remington Brass at 22 Caliber after trimming to about 0.005" over trim length. I only have to turn to the shoulder as the 20 caliber neck is completely formed without going into the shoulder. This virtually eliminates the formation of donuts as experience by people forming 20 Tactical brass, especially using 223 Lapua Match. My experience with the 20 practical led me to form a 20 EXTREME neck on 223 Lapua Match brass, which I did not even have to trim or adjust my K&M neck turning tool to do. I wound up with a nice 20-223 that I believe I will call the 20 Predator Extreme once I get a rifle chambered.
Forming 20 EXTREME Brass from Win 222 Rem. Notice that shoulder remains in the same position:
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Forming 20- 223 EXTREME from 223 Lapua Match brass. Turns slightly more into the shoulder due to the brass being more than 0.001" thicker but necks came out to a nice 0.012". Unlike the unturned neck on the left, I had to do a final trim (right( as the shoulder/neck moved forward about 0.008" on turning due to tension being relieved:
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I won't post any pictures of the targets I have shot with my 20 EXTREME as I believe you have seen many that illustrate my position. I had Hornady make dies for me and they are perfect in that brass forms with usually less than 0.005" neck run out. I do not need bushing dies as the die forms a 0.012" neck with about 0.0025" tension and the expander expands it by about 0.0005" which leave 0.002" neck tension which is about right for this cartridge. I do not need to bump shoulders and my seating die seats bullets with 0.0003 to an average of less than 0.0015". Perhaps not BR quality but most BR shooters and likely every hunter/varmint shooter would be more than happy with that.
If I start missing too many gophers at 300-400 meters I will get out the run out gauge to see if my loaded rounds are the problem. Otherwise I will just load and get to shooting.
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