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7-300 Norma Mag Improved. IT’S ALIVE!!

It seems nice for sure!!

Just ordered that new McMillan Mountaineer LR and I'll be putting the 7-300 into it whenever it arrives.
I played with the McMillan stuff at the sportsman's expo in Utah. They all seemed really heavy.
 
Yeah I think it'll land around 32oz. Which is fine with me for the bigger magnums. My current stock is 42oz. I'm not much of an "ultralight" anything guy lol
That's not bad. I was mostly playing with their adjustable stuff. Nobody seems to be able to touch the LRH. I'm at 10.5lbs suppressed on a NMI, my goal was 10 pounds but I couldn't get there. I don't understand you manly men with your 12 plus pound rifles. 😆
 
That's not bad. I was mostly playing with their adjustable stuff. Nobody seems to be able to touch the LRH. I'm at 10.5lbs suppressed on a NMI, my goal was 10 pounds but I couldn't get there. I don't understand you manly men with your 12 plus pound rifles. 😆
Oh my current 7-300 is 9.7lbs. But it'll be about 10.5lbs with the new barrel.

My gun was 12lbs last season. And while it was super stable and no recoil, it just didn't seem that necessary. Great to shoot, but not necessary for hunting
 
Build Spec:
Bat Vesper LA Lapua bolt face
Adjustable KS1 stock
Brux 1-9 twist #6 contour 26" finish
Bix n Andy tacsport
Hawkins Hunter DBM
Trijicon Tenmile 3-18X44
Unknown Munitions Premier Rings
Rifle 10.9lbs scoped

View attachment 547056

Goal for the build was to shoot 180 class bullets, specifically the 180 ELDM's around 3300fps, and stay below any pressure signs.

@Barehandlineman11 setup of the reamer design and ordered it. Based off the AW 300 NMI case body dimensions. But with a 7mm neck.

These next few pictures are a testament to @Barehandlineman11 and his meticulous work. Could not be happier to have him as my gunsmith. First class without a doubt.

Set out to fire form brass
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The first 5 rounds to go down this barrel. This is 180 ELDM's stuffed as far as they'll go into the lands with 90gr. H50. Just fire forming.
View attachment 547059

I zeroed it close enough and then this was the next 30 rounds, somewhat carelessly shot. With some cleaning in between.
View attachment 547060

Then I went to pressure testing with some formed brass from another 300 NMI chamber, that I necked down just to do a pressure test while I was out on the first range trip. So not ideal circumstances for accuracy.
View attachment 547063
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And here is the data for the two test powders. Retumbo will do 3300fps and stay below pressure. And N570 will probably do 3400fps. This was with CCI 250 primers. Forgot to include that in the writing.
View attachment 547065

Before and after forming. That's actually an old formed case from another gun, that I necked down to get land distance measurements. But you get the idea lol.
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180 ELDM Seated .020 off the lands
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The barrel will be cerakoted to match soon also. Just wanted to get out and shoot it.

There will be a lot more documentation going on here with this cartridge, since there is such little information on it out there.

Testing H1000 soon also.
Beautiful rig. Looks like a lot of fun.

No disrespect intended; why did you decide on a 9 twist in a custom 7mm that you wanted to shoot heavy for caliber pills? I thought the recommended barrel for a rig like this would be an 8 twist.
 
Beautiful rig. Looks like a lot of fun.

No disrespect intended; why did you decide on a 9 twist in a custom 7mm that you wanted to shoot heavy for caliber pills? I thought the recommended barrel for a rig like this would be an 8 twist.
No disrespect taken!!

I specifically wanted to shoot 180 ELDM's and I'm not a fan over twisting bullets if it's not necessary to actually stabilize them. 1-9 twist, at the high velocities, will stabilize pretty much everything except the big monos and the 190 A-tips.

Basically my intended bullets were 180 ELDM or 190 LRHT and 160 Copper Rose for a mono bullet. And 1-9 is just fine for those.
 
Interesting, I just ordered a Krieger 8.5tw, and im sorta nervous about the 190LRHT with it in 7Mega. But I'm only +140 MSL.
We shoot through invisible soup.
I shoot at sea level. The 1-9 stabilized the 190 LRHT no problem. And the 1-8.5 stabilized the 190 A-tip.

Yeah the mirage down here by the delta is terrible. I have to get any important shooting done before the sun even fully rises normally.
 
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