300 Norma Mag

Because usually it's just 50 fps or so compared to RETUMBO? I HATE getting rifles rebarreled, the wait time, the remeasurement and repeat load development and sighting in and break in and all that is a pain in the ass, and N570 is the ONE powder that guarantees you're going to be doing that more often. Unless you just shoot 50 rounds a year.
I got out of the 300 Norma and N570 because I started to care about barrel life. I don't need to spend 200 rds breaking in a barrel before it speeds up to maybe get another 500-600 rds out of it, only to start the process all over again.
 
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I don’t get how yall are spending more than 20-30 rounds doing load development. Everything after that is just shooting
For me, load development encompasses a lot more than it should, but I'm anal. I'm trying different powders, bullets, primers and seating depth at 100 and then verifying at 600 yards, and I lose sleep if I don't think I've exhausted all the potential into the load. But that's just me.
 
For me, load development encompasses a lot more than it should, but I'm anal. I'm trying different powders, bullets, primers and seating depth at 100 and then verifying at 600 yards, and I lose sleep if I don't think I've exhausted all the potential into the load. But that's just me.
Fair enough. I can completely see how that would get up there quickly. I do the painless method off rokslide.
 
I figured if they aren't going to let me get any more...there's no use in saving or sparing it. Might as well shoot up the 6-7 lbs I have left.
300 Norma Mag 35 Imp and I think it's a 28" barrel. I didn't want to go 30 cause I might shoot this suppressed one day.
I'm still working up loads but it's been cold as balls lately so I'll work on it more when it's more reasonable out. I may grab a pound of Ramshot LRT if people think it compares close to RL33. I've been a big fan of RL33 for the heavies (180-195gr bullets) in my 7 Rem Mag as well and always planned to use it in a 300 Norma Imp


I have a thread over at LRH I started because I didn't find much data for RL33 with 250s

Everything seems to be tracking out to 300 yds. Just about everything I feed it is sub 1/2.​
After running loads up to 94gr in a single charge to look for pressure. I decided to test the following 5 pairs in 0.2 incriments. Again, not looking for a load persay, just refining what kind of pressure we're seeing and lookign for loads that DON'T shoot.​
I've said in the past and I'll say it again. a 2 shot group doesn't tell you if a load WILL shoot...but it absolutely will tell you if a load WONT shoot.​
Still didn't really feel pressure but the Coup de Grâce is a little hard to "Feel" pressure so I'll measure some cases and decide after work how to proceed.​
93.6 - 3020 and 3007
93.8 - 3007 and 3051
94.0 - 3022 and 3022
94.2 - 3046 and 3060
94.6 - 3049 and 3039

300nmi300yds-png.634081



If I overlay all 6 of the shots from 94 to 94.4. It still shows sub 1/2 at 300 yds.
screenshot_20250111_155954_range-buddy-jpg.634091
 
I shoot a 300 norma improved but thinking about adding a straight 300 norma barrel so I don't have to improve for everything. What are you guys seeing performance wise n568 and n565 245 berger in the straight? What freebore you guys running for the 245?
With Retumbo (should be very close to 568) I’m getting 2895-2900: 81.0gr, 215M primers, Lapua brass, 245 Berger LRHT, 27” factory AI barrel. I shot a 16-round string Saturday with an SD under 5.
 
please explain. I have no interest in stepping up to a 338 can, regardless of the reason, but I'm curious why I would want to.
Because the 338 Ultra is one of the best and quietest cans out there, and you CAN step up to 338 rifles later if you change your mind. It works just as well on everything from 6.5 to 338 for me.
 
please explain. I have no interest in stepping up to a 338 can, regardless of the reason, but I'm curious why I would want to.

Because they weren't comfortable to shoot at all, either 24" up to 32" barrel, heavy profile or carbon fiber - didn't matter. Moving up to a .338 can made it feel more like shooting a suppressed .308WIN.

Edit: specifically the CGS Hekate DT
 
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Because the 338 Ultra is one of the best and quietest cans out there, and you CAN step up to 338 rifles later if you change your mind. It works just as well on everything from 6.5 to 338 for me.
I already have a 6.5 and .30 Ultra 9. You'd have a hard time convincing me a 338 Ultra 9 will suppress it better than a .30 Ultra 9

Alas, I won't be adding one anyway
 
please explain. I have no interest in stepping up to a 338 can, regardless of the reason, but I'm curious why I would want to.
I agree that 338 suppressors perform better for 300 NM loads. Suppressors are built to handle a certain amount of pressure and volume of propellant.

It’s been my experience that the larger 30 caliber suppressors sound great up to a propellant charge of 70ish grains of powder. The 338 cans handle up to 90-100 grains of powder and perform well. This is of course my experience and you need to confirm with the manufacturer as there are exceptions. For example many manufacturers do not recommend using their can with 30-378 and 33-378 cartridges even in their 338 caliber cans. These cartridges can utilize up to 120 grains of powder.

Many 30 caliber cans are rated for 300 NM but are not the best choice from a performance perspective, that is why the 338 cans are preferred.
 
I already have a 6.5 and .30 Ultra 9. You'd have a hard time convincing me a 338 Ultra 9 will suppress it better than a .30 Ultra 9

Alas, I won't be adding one anyway
I can’t imagine why it wouldn’t be intuitively obvious. I have 30 ultra and 338 ultra gen 2 and one of them is enormous compared to the other.

Volume matters and yeah it sounds great with 300nm
 
I already have a 6.5 and .30 Ultra 9. You'd have a hard time convincing me a 338 Ultra 9 will suppress it better than a .30 Ultra 9

Alas, I won't be adding one anyway
I couldn’t care less if I convince you of anything. You asked a question and I gave you an honest answer from my experience. But a 338 Ultra is not a “338 Ultra 9”. It’s 10-1/2”, not 9”. As we all know, suppression is volume-dependent, and the 338 Ultra has significantly more volume that a .30 Ultra 9. Look up TBAC’s dB suppression numbers and make your own conclusions.
 
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The new standard for 30 cal cans is goign to be the Magnus RR for something like 300NM.

I have a 338 ultra, going to step it up to 338 Ultra Gen2 RR, cuz - recoil
I’ll probably do that too, at some point, but now they’re hard to get. I’ve got 2 Ultra 338 Gen 1s, and just got a Gen 2 SR. The RR would be the next logical step.
 
I couldn’t care less if I convince you of anything. You asked a question and I gave you an honest answer from my experience. But a 338 Ultra is not a “338 Ultra 9”. It’s 10-1/2”, not 9”. As we all know, suppression is volume-dependent, and the 338 Ultra has significantly more volume that a .30 Ultra 9. Look up TBAC’s dB suppression numbers and make your own conclusions.
I've never had a need for a 338 can in the first place, so it's been YEARS since I even compared brands. I didn't realize it was a completely different model. Yes, obviously if there's that much of a volume difference it makes sense.
 
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Volume indeed seems to be the key. I confirmed that the other cans were obviously rated for .300NM before using them, but there appears to be a giant gulf between “yeah, it’s safe to shoot” and “hey, that’s pleasant to shoot.”
 
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I have the ultra 9 and shot it last year suppressed this year shooting faster with more powder and I put my brake on. The supressor was unpleasant to shoot high volume
 
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If you're worried about the unpleasantries, switch to a 308. You're burning 80-90 gr powder, pushing 230-250gr bullets, Big ass bullets going fast! Wtf do you expect? You're going to deal with recoil, or extreme muzzle blast from the large gas volume venting through a brake. Pick ur poison......or pick a different cartridge.
 
If you're worried about the unpleasantries, switch to a 308. You're burning 80-90 gr powder, pushing 230-250gr bullets, Big ass bullets going fast! Wtf do you expect? You're going to deal with recoil, or extreme muzzle blast from the large gas volume venting through a brake. Pick ur poison......or pick a different cartridge.
I might of not worded it correctly but I was saying the suppressor was unpleasant with the 300 norma ultra 9 that's why I switched to the brake.
 
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I might of not worded it correctly but I was saying the suppressor was unpleasant with the 300 norma ultra 9 that's why I switched to the brake.
I shoot a 11# 300nm imp, it's a hunting rifle. It suppressed with dead air lti XC, it's not too bad at all. Big can, still lots of push and no chance of spotting shots unless I'm on low mag and targets are past 400y. You're shooting an ELR cartridge, there's gonna be pros/cons. Maybe the 50cal tbac can might calm it down to 308 like recoil, but there is no free lunch here.
 
I shoot a 11# 300nm imp, it's a hunting rifle. It suppressed with dead air lti XC, it's not too bad at all. Big can, still lots of push and no chance of spotting shots unless I'm on low mag and targets are past 400y. You're shooting an ELR cartridge, there's gonna be pros/cons. Maybe the 50cal tbac can might calm it down to 308 like recoil, but there is no free lunch here.
I understand that and yeah I can shoot it no worries but putting 75 rds in 1 day at a match the brake is better. That's all I was saying. Think the bigger can would be better for the 300 norma
 
I am not gun shy lol about recoil by any means FFS I shoot 100s of rounds of 50 BMG and 375 Cheyenne tactical each year

But just cause I can tolerate it doesn’t mean I like it and nowadays with these advanced suppressors, like the thunder beast Magnus reduced recoil version, we can have it all and why wouldn’t you? I mean, of course, except for the wait time and the cost.
 
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I used to brake everything, now I have a ton of hearing loss even tho I wear muffs and or combo with plugs. Brakes will damage you're hearing regardless of how hard you try and fight the noise. I still wear in ear plugs with my suppressors if there's gonna be over 5 rds fired. I refuse to put a brake on things now, to keep what hearing I have left. Only way to quell the big cases, use the largest volume braked cans, add as much weight you can manage. If you want the velocity of the Norma capacity and the BC of the heaviest bullets, potential for heavy recoil is always gonna be there. There are expensive civilized ways to manage or the archaic cheap muzzle brake.
 
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I used to brake everything, now I have a ton of hearing loss even tho I wear muffs and or combo with plugs. Brakes will damage you're hearing regardless of how hard you try and fight the noise. I still wear in ear plugs with my suppressors if there's gonna be over 5 rds fired. I refuse to put a brake on things now, to keep what hearing I have left. Only way to quell the big cases, use the largest volume braked cans, add as much weight you can manage. If you want the velocity of the Norma capacity and the BC of the heaviest bullets, potential for heavy recoil is always gonna be there. There are expensive civilized ways to manage or the archaic cheap muzzle brake.
Shooting without a suppressor……

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With a 245? Best I can do is 2895 with a 230 in my AI factory-barrel 300PRC. I can manage about the same (2900) with a 245 in the factory 300NM barrel, and it's on the hot side. Tell us more about your 300PRC load.
Na 230 didn't remember his post earlier he was asking 245 loads. But I def run my prc about the same 2900. I can get 2950 it's pushing it. 79 gr of retumbo iirm will have to check my notes later.

I just had 2 300nm aw imp barrels chambered. I was hoping for at least 100ft a sec more with the same bullet
 
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Na 230 didn't remember his post earlier he was asking 245 loads. But I def run my prc about the same 2900. I can get 2950 it's pushing it. 79 gr of retumbo iirm will have to check my notes later.

I just had 2 300nm aw imp barrels chambered. I was hoping for at least 100ft a sec more with the same bullet
You can definitely push them hard and get some crazy speeds. N570 you can get almost 3100. I don't push things I run at lower pressure to balance everything out. I can get 3000 with my n568 but didn't see the reason for an extra 80 feet
 
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Na 230 didn't remember his post earlier he was asking 245 loads. But I def run my prc about the same 2900. I can get 2950 it's pushing it. 79 gr of retumbo iirm will have to check my notes later.

I just had 2 300nm aw imp barrels chambered. I was hoping for at least 100ft a sec more with the same bullet
I ran 230 at 3080 from a 26" 9tw w/ N570. 215s at 3190, same powder. Barrel had over 900rd on it when it would no longer hold a 5 shot group w/o a flyer. This was a 33° imp barrel.
 
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Na 230 didn't remember his post earlier he was asking 245 loads. But I def run my prc about the same 2900. I can get 2950 it's pushing it. 79 gr of retumbo iirm will have to check my notes later.

I just had 2 300nm aw imp barrels chambered. I was hoping for at least 100ft a sec more with the same bullet
Ok. I'm running 78.1gr Retumbo in the PRC with the 230, and 81.0gr in the Norma (not Improved) with the 245, both are 27" AI barrels.
 
Guys what should I do here. Normal 300NM out of factory AI 27” barrel.

Currently using 88.0 gr of N570, 215 Berger, lapua brass. Got 3055 fps. No pressure signs. Berger’s load data they sent me for lapua brass showed a max load of 90.2 gr, but only getting 2933 fps from a 26” barrel. So I’m already faster with 2.2gr less N570.

Should I keep going up until seeing pressure signs in the brass? Hornady’s max load with Hornady brass is 88 gr.

More velocity is always nice, but would I be gaining much here?
 
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Guys what should I do here. Normal 300NM out of factory AI 27” barrel.

Currently using 88.0 gr of N570, 215 Berger, lapua brass. Got 3055 fps. No pressure signs. Berger’s load data they sent me for lapua brass showed a max load of 90.2 gr, but only getting 2933 fps from a 26” barrel. So I’m already faster with 2.2gr less N570.

Should I keep going up until seeing pressure signs in the brass? Hornady’s max load with Hornady brass is 88 gr.

More velocity is always nice, but would I be gaining much here?
Sir this is snipers hide.... We start at overpressure get those rookie numbers up
 
Dammit that’s two conflicting opinions here…. Haha
The way I look at it is find what your happy with. Most people like above are shocked at what I run my 245s at in the improved but from 2925 to 3000 it's the same wind hold I would have to move to 3050 plus to get an advantage in wind according to the ballistics calators. So I find the best overall load for everything