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I come up with 2.219 to the rifling, with a Nosler 120 gr ballistic tip.
Waaay, shorter than the inside of my E lander mags.
Those have a more pronounced ogive than, say, the Hornady 123 family (SST, ELD). If you have access to some, try those and I’m certain they will load longer.
If it's true that we are here to help others, then what exactly are the others here for?
I come up with 2.219 to the rifling, with a Nosler 120 gr ballistic tip.
Waaay, shorter than the inside of my E lander mags.
OK, but be careful what you wish for.
In performance terms your loss of potential velocity is almost nothing.
I'm guessing your magazines give you an extra 1 - 2 mm of internal length than your current 2.219" barrel limit. Crunching the 'what-if' numbers on Quickload that amounts to an extra 0.3gns of powder which gives the same velocity out the end of your barrel at the longer OAL. But, what is in your favour here is being able to choose the best jump-to-lands down to 0". The rest of us have our mags limiting OAL and that means our jump-to-lands is often longer than preferred.
Your 2.219 is going to grow as that throat wears. In F-Class, where jump-to-lands makes a noticeable difference (and mag lengths are not an issue because you load each round by hand straight into the chamber) I used to measure jump-to-lands about every month and extend the OAL chasing the lands as it aged. Plus with every new box of bullets the shape of the bullets could be potentially different.
0.01" is a very short jump and no doubt every now and then you'll get a longer than average bullet that will touch the lands and spike your peak pressure. This will throw a flyer down range. Even in bolt guns I go no closer to the lands than .02". In a gas gun I doubt your .01 is even going to be noticed. Not saying this because I doubt your ability to load but the platform you are shooting it out of does no justice to such a small jump. What will be noticed however is the occasional flyer from a bullet touching lands.
I scratched the .010 jump and did .020, as a starting point with 3 powders. The .010 jump was with 30 grains of reldr 15. A difference due to not enough internal space.
Without adjusting the die, 28 grains of 748, the bullets measured at the .020 off, i had set up for, so did 28 grains of reldr 15.
Varget is next to load.
Splatt, are you measuring to the tip or the ogive? Your pic. shows to the tip. Most of the time the tips will be longer or shorter. Measuring to the ogive will be very close each time.
I use the bullet that I measure with to set my die for a specific off distance from the lands. My next go-around, I use another bullet, and measure with that bullet. I don't just measure once and start running things I've been doing this for way too many years.
Not questioning your reloading skills. I was wondering how you measured to the ogive? There are different ways to measure and was wondering how you did this as I don't see a comparator. I loaded some 120 NBT and they shot ok but best I remember they had to be seated deeper.
I use an oal casing. The bullet i use to touch the rifling is the one i use to deduct how ever many thousanths. It will be accurate using the same bullet. I use this bullet to load my first round. Then i use another bullet, measure load, and deduct off that first round.
It works very well.
I wanted to go yesterday, but the wind got up in the afternoon.
Now, we have high wind, and snow today.
Itll be a few days.
I think im going to scrap reldr15, and see what i can do with 748.
I need to go buy some other powders that are a fine ball, like 748.
My barrel has a short throat, so seating issues are happening due to less available internal space.
I've found there is too much variation in the bullet tip to use OAL for anything more than a reference point. I use Stoney Point/Hornady comparators to measure length and then setting seating depth from that point. There are other measuring devices such as the RCBS Precision Mic that will give you a similar measurement. I don't record OAL at all, only comparator length. Ballistic tip bullets are probably the best in terms of tip consistency but even they can vary a thousandth or three. If you combine tip inconsistency to seating depth variation you can potentially measure a cartridge that looks like it has .004" variation when it is nearly perfect.
Exactly. That is why I use the same bullet that I measure with to set up for whatever given depth I'm seating at. When I change seating depth to something else I use another bullet, RI measure, and use it. That way there is no variance. All the loadings there after are not touched it's based off of just that first initial one.
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