7-300 Norma Mag Improved

I don't see any in stock anywhere? I was going to get more haha. Send me a link if you don't mind!


Thanks man! Yeah it's pretty crazy, you definitely can't write the barrel off just based off the throat. Just have to shoot it until it fails, because I figured my forming barrel was TOAST
I had a .243 WIN with over 2,000 rounds on it that had chunks missing out of the throat and it still shot in the .3's... this was with monos though and might have skinned a lead bullet but looks are not how to judge a barrels performance.
 
Updated! Now weighs 10lbs 1oz šŸ™ŒšŸ¼. I decided not to do the new barrel. This barrel is hammering and I didn't feel like doing more load work haha. So this is the same #6 Brux.
View attachment 572170
Looks sick! I'd be curious to hear your thoughts on that stock once you do some shooting with it. Seems very well designed for recoil.

My 300 Norma is built on a bat vesper and I've been thinking about trying to get a nimrod to try. Where did you get yours from? Unknown munitions has them on backorder but I've been unable to get a hold of them...
 
Looks sick! I'd be curious to hear your thoughts on that stock once you do some shooting with it. Seems very well designed for recoil.

My 300 Norma is built on a bat vesper and I've been thinking about trying to get a nimrod to try. Where did you get yours from? Unknown munitions has them on backorder but I've been unable to get a hold of them...
I think I'm going to like it a lot! I got mine straight from Dallas. Just had an undersized barrel channel that I had to open up. Might be worth reaching out to him.
 
Looks sick! I'd be curious to hear your thoughts on that stock once you do some shooting with it. Seems very well designed for recoil.

My 300 Norma is built on a bat vesper and I've been thinking about trying to get a nimrod to try. Where did you get yours from? Unknown munitions has them on backorder but I've been unable to get a hold of them...
hit me up i may be able to help you outšŸ¤˜
 
following this awesome thread I decided to grab a box of the hornady 180 haven't used hornady in a long time but don't think this round got the new tips
 
I have a WTO 7-300NMI w/switch lug sitting in the safe I was going to finally start working with. I also had them spin up two barrels, one for fireforming and one for normal use. The question I have is whether I can neck down and just shoot to form, or does the 30-degree shoulder require me to use a false shoulder or jam the bullet into the lands?

I have 24lbs of N570, 20lbs of H1000 and 10lbs of Retumbo. I was going to fireform with LRT though to save the good (expensive) powders for load development. Have 1000 195's and 500 180 Hybrids hunting and targets.

Would like to hear feedback on your initial sizing and fireforming process.
 
I'd personally jam the lands just for reassurance. If the chamber doesn't have a good crush fit, you'll end up with a lot of inconsistencies in your formed brass.

N570 is crazy fast in this cartridge. But it caused more damage to the throat in 20 rounds, than H1000 did in 100 rounds. How much that actually affects barrel life and accuracy over how many rounds, I don't know yet.

My gun shot great with H1000 and 180 Hybrids though. 84gr. H1000 put them a little over 3150fps in a 26" barrel if I remember right.
 
So i got around to loading up 50 rounds yesterday for fire forming. I started out by making a dummy round with virgin Peterson brass and a Berger 180gr BT Match (Using those just for the fire forming) at 2.8760 base to ogive. I got that length by removing the ejector and firing pin from my Impact 787 and seating the bullet in increments until there was just a C-hairs worth of resistance to close the bolt, i think if I had gone another ten-thousandth it would have fallen with no assistance.

After chamfering the inside and outside of the case mouth I full length sized. The die set i got from WTO when i had the rifle built is a standard (non-bushing) Redding F/L sizing die with expander ball. After lubing the Peterson cases up and running the dummy round, I didn't like the amount, or how the drag from the ball felt on the down stroke of the sizing so I removed the decapping rod & expander ball and added another step by using an expander mandrel die from Porter Precision Products and a .2820+ expander. It felt a little weird going in, like it hit resistance, was fine, then resistance again on the way out by the neck shoulder junction (do I have a donut?).

WTO recommended 90g of LRT for fire forming 180 class bullets, so just because i dropped it to 89.5 and powdered all 50. When I was seating the bullets the majority went in really easy, almost too easy, like the weight of the handle would cause the ram to go up and seat the bullet very slowly, so I have to adjust my expander mandrel size. However, about 5 of the 50 seated with what I could call good resistance, so I'm not sure how that happened... the mystery of brass and reloading.

So I'm ready to fire form the first 50 now, just hope I can get to the range soon. On another note, LRT is a terrible powder to double charge a case by accident... it gets everywhere and is so TINY!!

I have a set of pin gauges so I'm going to see if I have a donut in the case after the firing, if I do I have a wilson 7mm inside neck reamer. Right now even if I do have a donut it's fine because the boattail junction of the bullet is above the neck shoulder junction.
 
So i got around to loading up 50 rounds yesterday for fire forming. I started out by making a dummy round with virgin Peterson brass and a Berger 180gr BT Match (Using those just for the fire forming) at 2.8760 base to ogive. I got that length by removing the ejector and firing pin from my Impact 787 and seating the bullet in increments until there was just a C-hairs worth of resistance to close the bolt, i think if I had gone another ten-thousandth it would have fallen with no assistance.

After chamfering the inside and outside of the case mouth I full length sized. The die set i got from WTO when i had the rifle built is a standard (non-bushing) Redding F/L sizing die with expander ball. After lubing the Peterson cases up and running the dummy round, I didn't like the amount, or how the drag from the ball felt on the down stroke of the sizing so I removed the decapping rod & expander ball and added another step by using an expander mandrel die from Porter Precision Products and a .2820+ expander. It felt a little weird going in, like it hit resistance, was fine, then resistance again on the way out by the neck shoulder junction (do I have a donut?).

WTO recommended 90g of LRT for fire forming 180 class bullets, so just because i dropped it to 89.5 and powdered all 50. When I was seating the bullets the majority went in really easy, almost too easy, like the weight of the handle would cause the ram to go up and seat the bullet very slowly, so I have to adjust my expander mandrel size. However, about 5 of the 50 seated with what I could call good resistance, so I'm not sure how that happened... the mystery of brass and reloading.

So I'm ready to fire form the first 50 now, just hope I can get to the range soon. On another note, LRT is a terrible powder to double charge a case by accident... it gets everywhere and is so TINY!!

I have a set of pin gauges so I'm going to see if I have a donut in the case after the firing, if I do I have a wilson 7mm inside neck reamer. Right now even if I do have a donut it's fine because the boattail junction of the bullet is above the neck shoulder junction.
I sized my necks down in 2 steps. I tried 1 stepping it initially and it gave me a pretty good donut.

I seated my bullets like .060 into the lands for forming.

It's all a big learning process and you'll learn what works for you and the case as well!

I learned a lot about reloading when I started messing with wildcats. It's like a trial by fire haha. But worth it in the end
 
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